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  • Webcam api error when accessed from ASP.NET Server-side code

    - by Eyla
    I'm tring to use webcam api with asp.net and C#. I included all the library and references I needed for that. the original code I'm use was for windows application and I'm trying to convert it to asp.net web application. I have start capturing button when I click it, it should start capturing but it gives me an error. the error at this line: hHwnd = capCreateCaptureWindowA(iDevice.ToString(), (WS_VISIBLE | WS_CHILD), 0, 0, 640, 480, picCapture.Handle.ToInt32(), 0); and the error message is: Error 1 'System.Web.UI.WebControls.Image' does not contain a definition for 'Handle' and no extension method 'Handle' accepting a first argument of type 'System.Web.UI.WebControls.Image' could be found (are you missing a using directive or an assembly reference?) C:\Users\Ali\Documents\Visual Studio 2008\Projects\Conference\Conference\Conference1.aspx.cs 63 117 Conference Please advice!! ................................................ here is the complete code ........................................... using System; using System.Collections; using System.Drawing; using System.ComponentModel; using System.Windows.Forms; using System.Configuration; using System.Data; using System.Linq; using System.Web; using System.Web.Security; using System.Web.UI; using System.Web.UI.HtmlControls; using System.Web.UI.WebControls; using System.Web.UI.WebControls.WebParts; using System.Xml.Linq; using System.Runtime.InteropServices; using System.Drawing.Imaging; using System.Net; using System.Net.Sockets; using System.Threading; using System.IO; namespace Conference { public partial class Conference1 : System.Web.UI.Page { #region WebCam API const short WM_CAP = 1024; const int WM_CAP_DRIVER_CONNECT = WM_CAP + 10; const int WM_CAP_DRIVER_DISCONNECT = WM_CAP + 11; const int WM_CAP_EDIT_COPY = WM_CAP + 30; const int WM_CAP_SET_PREVIEW = WM_CAP + 50; const int WM_CAP_SET_PREVIEWRATE = WM_CAP + 52; const int WM_CAP_SET_SCALE = WM_CAP + 53; const int WS_CHILD = 1073741824; const int WS_VISIBLE = 268435456; const short SWP_NOMOVE = 2; const short SWP_NOSIZE = 1; const short SWP_NOZORDER = 4; const short HWND_BOTTOM = 1; int iDevice = 0; int hHwnd; [System.Runtime.InteropServices.DllImport("user32", EntryPoint = "SendMessageA")] static extern int SendMessage(int hwnd, int wMsg, int wParam, [MarshalAs(UnmanagedType.AsAny)] object lParam); [System.Runtime.InteropServices.DllImport("user32", EntryPoint = "SetWindowPos")] static extern int SetWindowPos(int hwnd, int hWndInsertAfter, int x, int y, int cx, int cy, int wFlags); [System.Runtime.InteropServices.DllImport("user32")] static extern bool DestroyWindow(int hndw); [System.Runtime.InteropServices.DllImport("avicap32.dll")] static extern int capCreateCaptureWindowA(string lpszWindowName, int dwStyle, int x, int y, int nWidth, short nHeight, int hWndParent, int nID); [System.Runtime.InteropServices.DllImport("avicap32.dll")] static extern bool capGetDriverDescriptionA(short wDriver, string lpszName, int cbName, string lpszVer, int cbVer); private void OpenPreviewWindow() { int iHeight = 320; int iWidth = 200; // // Open Preview window in picturebox // hHwnd = capCreateCaptureWindowA(iDevice.ToString(), (WS_VISIBLE | WS_CHILD), 0, 0, 640, 480, picCapture.Handle.ToInt32(), 0); // // Connect to device // if (SendMessage(hHwnd, WM_CAP_DRIVER_CONNECT, iDevice, 0) == 1) { // // Set the preview scale // SendMessage(hHwnd, WM_CAP_SET_SCALE, 1, 0); // // Set the preview rate in milliseconds // SendMessage(hHwnd, WM_CAP_SET_PREVIEWRATE, 66, 0); // // Start previewing the image from the camera // SendMessage(hHwnd, WM_CAP_SET_PREVIEW, 1, 0); // // Resize window to fit in picturebox // SetWindowPos(hHwnd, HWND_BOTTOM, 0, 0, iWidth, iHeight, (SWP_NOMOVE | SWP_NOZORDER)); } else { // // Error connecting to device close window // DestroyWindow(hHwnd); } } private void ClosePreviewWindow() { // // Disconnect from device // SendMessage(hHwnd, WM_CAP_DRIVER_DISCONNECT, iDevice, 0); // // close window // DestroyWindow(hHwnd); } #endregion protected void Page_Load(object sender, EventArgs e) { } protected void btnStart_Click(object sender, EventArgs e) { int iDevice = int.Parse(device_number_textBox.Text); OpenPreviewWindow(); } } }

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  • Asp.Net Login control (Visual Web Dev)

    - by craig
    This is the code when you take the Login control from the toolbox. <%@ Page Language="C#" AutoEventWireup="true" CodeFile="Default.aspx.cs" Inherits="_Default" %> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head runat="server"> <title></title> </head> <body> <form id="form1" runat="server"> <div> <asp:Login ID="Login1" runat="server" onauthenticate="Login1_Authenticate" BackColor="#F7F7DE" BorderColor="#CCCC99" BorderStyle="Solid" BorderWidth="1px" Font-Names="Verdana" Font-Size="10pt"> <LayoutTemplate> <table border="0" cellpadding="1" cellspacing="0" style="border-collapse:collapse;"> <tr> <td> <table border="0" cellpadding="0"> <tr> <td align="center" colspan="2"> Log In</td> </tr> <tr> <td align="right"> <asp:Label ID="UserNameLabel" runat="server" AssociatedControlID="UserName">User Name:</asp:Label> </td> <td> <asp:TextBox ID="UserName" runat="server" ></asp:TextBox> <asp:RequiredFieldValidator ID="UserNameRequired" runat="server" ControlToValidate="UserName" ErrorMessage="User Name is required." ToolTip="User Name is required." ValidationGroup="Login1">*</asp:RequiredFieldValidator> </td> </tr> <tr> <td align="right"> <asp:Label ID="PasswordLabel" runat="server" AssociatedControlID="Password">Password:</asp:Label> </td> <td> <asp:TextBox ID="Password" runat="server" TextMode="Password"></asp:TextBox> <asp:RequiredFieldValidator ID="PasswordRequired" runat="server" ControlToValidate="Password" ErrorMessage="Password is required." ToolTip="Password is required." ValidationGroup="Login1">*</asp:RequiredFieldValidator> </td> </tr> <tr> <td colspan="2"> <asp:CheckBox ID="RememberMe" runat="server" Text="Remember me next time." /> </td> </tr> <tr> <td align="center" colspan="2" style="color:Red;"> <asp:Literal ID="FailureText" runat="server" EnableViewState="False"></asp:Literal> </td> </tr> <tr> <td align="right" colspan="2"> <asp:Button ID="LoginButton" runat="server" CommandName="Login" Text="Log In" ValidationGroup="Login1" onclick="LoginButton_Click" /> </td> </tr> </table> </td> </tr> </table> </LayoutTemplate> <TitleTextStyle BackColor="#6B696B" Font-Bold="True" ForeColor="#FFFFFF" /> </asp:Login> </div> </form> </body> </html> Part of my aspx.cs protected void LoginButton_Click(object sender, EventArgs e) { String sUserName = UserName.Text; String sPassword = Password.Text; Error 1 The name 'UserName' does not exist in the current context Error 2 The name 'Password' does not exist in the current context Error 3 'ASP.default_aspx' does not contain a definition for 'Login1_Authenticate' and no extension method 'Login1_Authenticate' accepting a first argument of type 'ASP.default_aspx' could be found (are you missing a using directive or an assembly reference?) What am I doing wrong?

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  • Prefer extension methods for encapsulation and reusability?

    - by tzaman
    edit4: wikified, since this seems to have morphed more into a discussion than a specific question. In C++ programming, it's generally considered good practice to "prefer non-member non-friend functions" instead of instance methods. This has been recommended by Scott Meyers in this classic Dr. Dobbs article, and repeated by Herb Sutter and Andrei Alexandrescu in C++ Coding Standards (item 44); the general argument being that if a function can do its job solely by relying on the public interface exposed by the class, it actually increases encapsulation to have it be external. While this confuses the "packaging" of the class to some extent, the benefits are generally considered worth it. Now, ever since I've started programming in C#, I've had a feeling that here is the ultimate expression of the concept that they're trying to achieve with "non-member, non-friend functions that are part of a class interface". C# adds two crucial components to the mix - the first being interfaces, and the second extension methods: Interfaces allow a class to formally specify their public contract, the methods and properties that they're exposing to the world. Any other class can choose to implement the same interface and fulfill that same contract. Extension methods can be defined on an interface, providing any functionality that can be implemented via the interface to all implementers automatically. And best of all, because of the "instance syntax" sugar and IDE support, they can be called the same way as any other instance method, eliminating the cognitive overhead! So you get the encapsulation benefits of "non-member, non-friend" functions with the convenience of members. Seems like the best of both worlds to me; the .NET library itself providing a shining example in LINQ. However, everywhere I look I see people warning against extension method overuse; even the MSDN page itself states: In general, we recommend that you implement extension methods sparingly and only when you have to. (edit: Even in the current .NET library, I can see places where it would've been useful to have extensions instead of instance methods - for example, all of the utility functions of List<T> (Sort, BinarySearch, FindIndex, etc.) would be incredibly useful if they were lifted up to IList<T> - getting free bonus functionality like that adds a lot more benefit to implementing the interface.) So what's the verdict? Are extension methods the acme of encapsulation and code reuse, or am I just deluding myself? (edit2: In response to Tomas - while C# did start out with Java's (overly, imo) OO mentality, it seems to be embracing more multi-paradigm programming with every new release; the main thrust of this question is whether using extension methods to drive a style change (towards more generic / functional C#) is useful or worthwhile..) edit3: overridable extension methods The only real problem identified so far with this approach, is that you can't specialize extension methods if you need to. I've been thinking about the issue, and I think I've come up with a solution. Suppose I have an interface MyInterface, which I want to extend - I define my extension methods in a MyExtension static class, and pair it with another interface, call it MyExtensionOverrider. MyExtension methods are defined according to this pattern: public static int MyMethod(this MyInterface obj, int arg, bool attemptCast=true) { if (attemptCast && obj is MyExtensionOverrider) { return ((MyExtensionOverrider)obj).MyMethod(arg); } // regular implementation here } The override interface mirrors all of the methods defined in MyExtension, except without the this or attemptCast parameters: public interface MyExtensionOverrider { int MyMethod(int arg); string MyOtherMethod(); } Now, any class can implement the interface and get the default extension functionality: public class MyClass : MyInterface { ... } Anyone that wants to override it with specific implementations can additionally implement the override interface: public class MySpecializedClass : MyInterface, MyExtensionOverrider { public int MyMethod(int arg) { //specialized implementation for one method } public string MyOtherMethod() { // fallback to default for others MyExtension.MyOtherMethod(this, attemptCast: false); } } And there we go: extension methods provided on an interface, with the option of complete extensibility if needed. Fully general too, the interface itself doesn't need to know about the extension / override, and multiple extension / override pairs can be implemented without interfering with each other. I can see three problems with this approach - It's a little bit fragile - the extension methods and override interface have to be kept synchronized manually. It's a little bit ugly - implementing the override interface involves boilerplate for every function you don't want to specialize. It's a little bit slow - there's an extra bool comparison and cast attempt added to the mainline of every method. Still, all those notwithstanding, I think this is the best we can get until there's language support for interface functions. Thoughts?

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  • How to merge two different Makefiles?

    - by martijnn2008
    I have did some reading on "Merging Makefiles", one suggest I should leave the two Makefiles separate in different folders [1]. For me this look counter intuitive, because I have the following situation: I have 3 source files (main.cpp flexibility.cpp constraints.cpp) one of them (flexibility.cpp) is making use of the COIN-OR Linear Programming library (Clp) When installing this library on my computer it makes sample Makefiles, which I have adjust the Makefile and it currently makes a good working binary. # Copyright (C) 2006 International Business Machines and others. # All Rights Reserved. # This file is distributed under the Eclipse Public License. # $Id: Makefile.in 726 2006-04-17 04:16:00Z andreasw $ ########################################################################## # You can modify this example makefile to fit for your own program. # # Usually, you only need to change the five CHANGEME entries below. # ########################################################################## # To compile other examples, either changed the following line, or # add the argument DRIVER=problem_name to make DRIVER = main # CHANGEME: This should be the name of your executable EXE = clp # CHANGEME: Here is the name of all object files corresponding to the source # code that you wrote in order to define the problem statement OBJS = $(DRIVER).o constraints.o flexibility.o # CHANGEME: Additional libraries ADDLIBS = # CHANGEME: Additional flags for compilation (e.g., include flags) ADDINCFLAGS = # CHANGEME: Directory to the sources for the (example) problem definition # files SRCDIR = . ########################################################################## # Usually, you don't have to change anything below. Note that if you # # change certain compiler options, you might have to recompile the # # COIN package. # ########################################################################## COIN_HAS_PKGCONFIG = TRUE COIN_CXX_IS_CL = #TRUE COIN_HAS_SAMPLE = TRUE COIN_HAS_NETLIB = #TRUE # C++ Compiler command CXX = g++ # C++ Compiler options CXXFLAGS = -O3 -pipe -DNDEBUG -pedantic-errors -Wparentheses -Wreturn-type -Wcast-qual -Wall -Wpointer-arith -Wwrite-strings -Wconversion -Wno-unknown-pragmas -Wno-long-long -DCLP_BUILD # additional C++ Compiler options for linking CXXLINKFLAGS = -Wl,--rpath -Wl,/home/martijn/Downloads/COIN/coin-Clp/lib # C Compiler command CC = gcc # C Compiler options CFLAGS = -O3 -pipe -DNDEBUG -pedantic-errors -Wimplicit -Wparentheses -Wsequence-point -Wreturn-type -Wcast-qual -Wall -Wno-unknown-pragmas -Wno-long-long -DCLP_BUILD # Sample data directory ifeq ($(COIN_HAS_SAMPLE), TRUE) ifeq ($(COIN_HAS_PKGCONFIG), TRUE) CXXFLAGS += -DSAMPLEDIR=\"`PKG_CONFIG_PATH=/home/martijn/Downloads/COIN/coin-Clp/lib64/pkgconfig:/home/martijn/Downloads/COIN/coin-Clp/lib/pkgconfig:/home/martijn/Downloads/COIN/coin-Clp/share/pkgconfig: pkg-config --variable=datadir coindatasample`\" CFLAGS += -DSAMPLEDIR=\"`PKG_CONFIG_PATH=/home/martijn/Downloads/COIN/coin-Clp/lib64/pkgconfig:/home/martijn/Downloads/COIN/coin-Clp/lib/pkgconfig:/home/martijn/Downloads/COIN/coin-Clp/share/pkgconfig: pkg-config --variable=datadir coindatasample`\" else CXXFLAGS += -DSAMPLEDIR=\"\" CFLAGS += -DSAMPLEDIR=\"\" endif endif # Netlib data directory ifeq ($(COIN_HAS_NETLIB), TRUE) ifeq ($(COIN_HAS_PKGCONFIG), TRUE) CXXFLAGS += -DNETLIBDIR=\"`PKG_CONFIG_PATH=/home/martijn/Downloads/COIN/coin-Clp/lib64/pkgconfig:/home/martijn/Downloads/COIN/coin-Clp/lib/pkgconfig:/home/martijn/Downloads/COIN/coin-Clp/share/pkgconfig: pkg-config --variable=datadir coindatanetlib`\" CFLAGS += -DNETLIBDIR=\"`PKG_CONFIG_PATH=/home/martijn/Downloads/COIN/coin-Clp/lib64/pkgconfig:/home/martijn/Downloads/COIN/coin-Clp/lib/pkgconfig:/home/martijn/Downloads/COIN/coin-Clp/share/pkgconfig: pkg-config --variable=datadir coindatanetlib`\" else CXXFLAGS += -DNETLIBDIR=\"\" CFLAGS += -DNETLIBDIR=\"\" endif endif # Include directories (we use the CYGPATH_W variables to allow compilation with Windows compilers) ifeq ($(COIN_HAS_PKGCONFIG), TRUE) INCL = `PKG_CONFIG_PATH=/home/martijn/Downloads/COIN/coin-Clp/lib64/pkgconfig:/home/martijn/Downloads/COIN/coin-Clp/lib/pkgconfig:/home/martijn/Downloads/COIN/coin-Clp/share/pkgconfig: pkg-config --cflags clp` else INCL = endif INCL += $(ADDINCFLAGS) # Linker flags ifeq ($(COIN_HAS_PKGCONFIG), TRUE) LIBS = `PKG_CONFIG_PATH=/home/martijn/Downloads/COIN/coin-Clp/lib64/pkgconfig:/home/martijn/Downloads/COIN/coin-Clp/lib/pkgconfig:/home/martijn/Downloads/COIN/coin-Clp/share/pkgconfig: pkg-config --libs clp` else ifeq ($(COIN_CXX_IS_CL), TRUE) LIBS = -link -libpath:`$(CYGPATH_W) /home/martijn/Downloads/COIN/coin-Clp/lib` libClp.lib else LIBS = -L/home/martijn/Downloads/COIN/coin-Clp/lib -lClp endif endif # The following is necessary under cygwin, if native compilers are used CYGPATH_W = echo # Here we list all possible generated objects or executables to delete them CLEANFILES = clp \ main.o \ flexibility.o \ constraints.o \ all: $(EXE) .SUFFIXES: .cpp .c .o .obj $(EXE): $(OBJS) bla=;\ for file in $(OBJS); do bla="$$bla `$(CYGPATH_W) $$file`"; done; \ $(CXX) $(CXXLINKFLAGS) $(CXXFLAGS) -o $@ $$bla $(LIBS) $(ADDLIBS) clean: rm -rf $(CLEANFILES) .cpp.o: $(CXX) $(CXXFLAGS) $(INCL) -c -o $@ `test -f '$<' || echo '$(SRCDIR)/'`$< .cpp.obj: $(CXX) $(CXXFLAGS) $(INCL) -c -o $@ `if test -f '$<'; then $(CYGPATH_W) '$<'; else $(CYGPATH_W) '$(SRCDIR)/$<'; fi` .c.o: $(CC) $(CFLAGS) $(INCL) -c -o $@ `test -f '$<' || echo '$(SRCDIR)/'`$< .c.obj: $(CC) $(CFLAGS) $(INCL) -c -o $@ `if test -f '$<'; then $(CYGPATH_W) '$<'; else $(CYGPATH_W) '$(SRCDIR)/$<'; fi` The other Makefile compiles a lot of code and makes use of bison and flex. This one is also made by someone else. I am able to alter this Makefile when I want to add some code. This Makefile also makes a binary. CFLAGS=-Wall LDLIBS=-LC:/GnuWin32/lib -lfl -lm LSOURCES=lex.l YSOURCES=grammar.ypp CSOURCES=debug.cpp esta_plus.cpp heap.cpp main.cpp stjn.cpp timing.cpp tmsp.cpp token.cpp chaining.cpp flexibility.cpp exceptions.cpp HSOURCES=$(CSOURCES:.cpp=.h) includes.h OBJECTS=$(LSOURCES:.l=.o) $(YSOURCES:.ypp=.tab.o) $(CSOURCES:.cpp=.o) all: solver solver: CFLAGS+=-g -O0 -DDEBUG solver: $(OBJECTS) main.o debug.o g++ $(CFLAGS) -o $@ $^ $(LDLIBS) solver.release: CFLAGS+=-O5 solver.release: $(OBJECTS) main.o g++ $(CFLAGS) -o $@ $^ $(LDLIBS) %.o: %.cpp g++ -c $(CFLAGS) -o $@ $< lex.cpp: lex.l grammar.tab.cpp grammar.tab.hpp flex -o$@ $< %.tab.cpp %.tab.hpp: %.ypp bison --verbose -d $< ifneq ($(LSOURCES),) $(LSOURCES:.l=.cpp): $(YSOURCES:.y=.tab.h) endif -include $(OBJECTS:.o=.d) clean: rm -f $(OBJECTS) $(OBJECTS:.o=.d) $(YSOURCES:.ypp=.tab.cpp) $(YSOURCES:.ypp=.tab.hpp) $(YSOURCES:.ypp=.output) $(LSOURCES:.l=.cpp) solver solver.release 2>/dev/null .PHONY: all clean debug release Both of these Makefiles are, for me, hard to understand. I don't know what they exactly do. What I want is to merge the two of them so I get only one binary. The code compiled in the second Makefile should be the result. I want to add flexibility.cpp and constraints.cpp to the second Makefile, but when I do. I get the problem following problem: flexibility.h:4:26: fatal error: ClpSimplex.hpp: No such file or directory #include "ClpSimplex.hpp" So the compiler can't find the Clp library. I also tried to copy-paste more code from the first Makefile into the second, but it still gives me that same error. Q: Can you please help me with merging the two makefiles or pointing out a more elegant way? Q: In this case is it indeed better to merge the two Makefiles? I also tried to use cmake, but I gave upon that one quickly, because I don't know much about flex and bison.

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  • Zend_Navigation failing to load

    - by Grant Collins
    Hi, Following on from my earlier question, I am still having issues with loading the xml file into Zend_Navigation. I am now getting the following error message: <b>Fatal error</b>: Uncaught exception 'Zend_Navigation_Exception' with message 'Invalid argument: Unable to determine class to instantiate' in C:\www\mysite\development\website\library\Zend\Navigation\Page.php:223 I've tried to make my navigation.xml file look similar to the example on the Zend Documentation, However I just can't seem to get it to work. My XML file looks like this: <?xml version="1.0" encoding="UTF-8"?> <configdata> <navigation> <default> <label>Home</label> <controller>index</controller> <action>index</action> <module>default</module> <pages> <tour> <label>Tour</label> <controller>tour</controller> <action>index</action> <module>default</module> </tour> <blog> <label></label> <uri>http://blog.mysite.com</uri> </blog> <support> <label>Support</label> <controller>support</controller> <action>index</action> <module>default</module> </support> </pages> </default> <users> <label>Home</label> <controller>index</controller> <action>index</action> <module>users</module> <role>guser</role> <resource>owner</resource> <pages> <jobmanger> <label>Job Manager</label> <controller>jobmanager</controller> <action>index</action> <module>users</module> <role>guser</role> <resource>owner</resource> </jobmanger> <myaccount> <label>My Account</label> <controller>profile</controller> <action>index</action> <role>guser</role> <resource>owner</resource> <module>users</module> <pages> <detail> <label>Account Details</label> <controller>profile</controller> <action>detail</action> <module>users</module> <role>guser</role> <resource>owner</resource> <pages> <history> <label>Account History</label> <controller>profile</controller> <action>history</action> <module>users</module> <role>guser</role> <resource>owner</resource> </history> <password> <label>Change Password</label> <controller>profile</controller> <action>changepwd</action> <module>users</module> <role>employer</role> <resource>employers</resource> </password> </pages> </detail> ... </navigation> </configdata> Now I confess that I've totally got the wrong end of the stick with this, but rapidly running out of ideas, and it's been a long week. Thanks, Grant

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  • I don't get prices with Amazon Product Advertising API

    - by Xarem
    I try to get prices of an ASIN number with the Amazon Product Advertising API. Code: $artNr = "B003TKSD8E"; $base_url = "http://ecs.amazonaws.de/onca/xml"; $params = array( 'AWSAccessKeyId' => self::API_KEY, 'AssociateTag' => self::API_ASSOCIATE_TAG, 'Version' => "2010-11-01", 'Operation' => "ItemLookup", 'Service' => "AWSECommerceService", 'Condition' => "All", 'IdType' => 'ASIN', 'ItemId' => $artNr); $params['Timestamp'] = gmdate("Y-m-d\TH:i:s.\\0\\0\\0\\Z", time()); $url_parts = array(); foreach(array_keys($params) as $key) $url_parts[] = $key . "=" . str_replace('%7E', '~', rawurlencode($params[$key])); sort($url_parts); $url_string = implode("&", $url_parts); $string_to_sign = "GET\necs.amazonaws.de\n/onca/xml\n" . $url_string; $signature = hash_hmac("sha256", $string_to_sign, self::API_SECRET, TRUE); $signature = urlencode(base64_encode($signature)); $url = $base_url . '?' . $url_string . "&Signature=" . $signature; $response = file_get_contents($url); $parsed_xml = simplexml_load_string($response); I think this should be correct - but I don't get offers in the response: SimpleXMLElement Object ( [OperationRequest] => SimpleXMLElement Object ( [RequestId] => ************************* [Arguments] => SimpleXMLElement Object ( [Argument] => Array ( [0] => SimpleXMLElement Object ( [@attributes] => Array ( [Name] => Condition [Value] => All ) ) [1] => SimpleXMLElement Object ( [@attributes] => Array ( [Name] => Operation [Value] => ItemLookup ) ) [2] => SimpleXMLElement Object ( [@attributes] => Array ( [Name] => Service [Value] => AWSECommerceService ) ) [3] => SimpleXMLElement Object ( [@attributes] => Array ( [Name] => ItemId [Value] => B003TKSD8E ) ) [4] => SimpleXMLElement Object ( [@attributes] => Array ( [Name] => IdType [Value] => ASIN ) ) [5] => SimpleXMLElement Object ( [@attributes] => Array ( [Name] => AWSAccessKeyId [Value] => ************************* ) ) [6] => SimpleXMLElement Object ( [@attributes] => Array ( [Name] => Timestamp [Value] => 2011-11-29T01:32:12.000Z ) ) [7] => SimpleXMLElement Object ( [@attributes] => Array ( [Name] => Signature [Value] => ************************* ) ) [8] => SimpleXMLElement Object ( [@attributes] => Array ( [Name] => AssociateTag [Value] => ************************* ) ) [9] => SimpleXMLElement Object ( [@attributes] => Array ( [Name] => Version [Value] => 2010-11-01 ) ) ) ) [RequestProcessingTime] => 0.0091540000000000 ) [Items] => SimpleXMLElement Object ( [Request] => SimpleXMLElement Object ( [IsValid] => True [ItemLookupRequest] => SimpleXMLElement Object ( [Condition] => All [IdType] => ASIN [ItemId] => B003TKSD8E [ResponseGroup] => Small [VariationPage] => All ) ) [Item] => SimpleXMLElement Object ( [ASIN] => B003TKSD8E [DetailPageURL] => http://www.amazon.de/Apple-iPhone-4-32GB-schwarz/dp/B003TKSD8E%3FSubscriptionId%3DAKIAI6NFQHK2DQIPRUEQ%26tag%3Dbanholzerme-20%26linkCode%3Dxm2%26camp%3D2025%26creative%3D165953%26creativeASIN%3DB003TKSD8E [ItemLinks] => SimpleXMLElement Object ( [ItemLink] => Array ( [0] => SimpleXMLElement Object ( [Description] => Add To Wishlist [URL] => http://www.amazon.de/gp/registry/wishlist/add-item.html%3Fasin.0%3DB003TKSD8E%26SubscriptionId%3DAKIAI6NFQHK2DQIPRUEQ%26tag%3Dbanholzerme-20%26linkCode%3Dxm2%26camp%3D2025%26creative%3D12738%26creativeASIN%3DB003TKSD8E ) [1] => SimpleXMLElement Object ( [Description] => Tell A Friend [URL] => http://www.amazon.de/gp/pdp/taf/B003TKSD8E%3FSubscriptionId%3DAKIAI6NFQHK2DQIPRUEQ%26tag%3Dbanholzerme-20%26linkCode%3Dxm2%26camp%3D2025%26creative%3D12738%26creativeASIN%3DB003TKSD8E ) [2] => SimpleXMLElement Object ( [Description] => All Customer Reviews [URL] => http://www.amazon.de/review/product/B003TKSD8E%3FSubscriptionId%3DAKIAI6NFQHK2DQIPRUEQ%26tag%3Dbanholzerme-20%26linkCode%3Dxm2%26camp%3D2025%26creative%3D12738%26creativeASIN%3DB003TKSD8E ) [3] => SimpleXMLElement Object ( [Description] => All Offers [URL] => http://www.amazon.de/gp/offer-listing/B003TKSD8E%3FSubscriptionId%3DAKIAI6NFQHK2DQIPRUEQ%26tag%3Dbanholzerme-20%26linkCode%3Dxm2%26camp%3D2025%26creative%3D12738%26creativeASIN%3DB003TKSD8E ) ) ) [ItemAttributes] => SimpleXMLElement Object ( [Manufacturer] => Apple Computer [ProductGroup] => CE [Title] => Apple iPhone 4 32GB schwarz ) ) ) ) Can someone please explain me why I don't get any price-information? Thank you very much

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  • Printing an array in a method, from a different class?

    - by O.Lodhi
    Hello All, I'm a fairly inexperienced programmer, and i'm currently working on a Console Application project. It's basically a little 'mathematics game'; the application generates two random numbers, that have either been added, subtracted, multiplied or divided against each other randomly. The answer is shown on screen and the user has to pick from the menu which is the right mathematical operator, once the correct answer is picked the application then displays on screen how long it took for the user in milliseconds to input the correct answer. Now I want to save the times of the players in an array that can be called up later with all the scores. I need to include a method in this programme and I figured a method to save the times into an array would be suitable. I seem to have stumbled across a little problem though. I'm not quite sure what's wrong: using System; using System.Collections.Generic; using System.Linq; using System.Text; namespace Mathgame { class Program { } class arrayclass { public static void saveInArray(int duration) { int[] TopTenScores = {000,1000,2000,3000,4000,5000,6000,7000,8000,9000}; if (duration < 1000) { duration = TopTenScores[000]; } else if ((duration >= 1000) && (duration <= 1999)) { duration = TopTenScores[1000]; } else if ((duration >= 2000) && (duration <= 2999)) { duration = TopTenScores[2000]; } else if ((duration >= 3000) && (duration <= 3999)) { duration = TopTenScores[3000]; } else if ((duration >= 4000) && (duration <= 4999)) { duration = TopTenScores[4000]; } else if ((duration >= 5000) && (duration <= 5999)) { duration = TopTenScores[5000]; } else if ((duration >= 6000) && (duration <= 6999)) { duration = TopTenScores[6000]; } else if ((duration >= 7000) && (duration <= 7999)) { duration = TopTenScores[7000]; } else if ((duration >= 8000) && (duration <= 8999)) { duration = TopTenScores[8000]; } else if ((duration >= 9000) && (duration <= 9999)) { duration = TopTenScores[9000]; } Console.WriteLine(TopTenScores); } static void Main(string[] args) { int intInput, num1, num2, incorrect, array1; float answer; string input; System.Random randNum = new System.Random(); Console.WriteLine("Welcome to the Maths game!"); Console.WriteLine("(Apologies for the glitchiness!)"); Console.WriteLine(); Console.WriteLine("Please choose from the following options:"); Console.WriteLine(); retry: Console.WriteLine("1 - Test your Maths against the clock!"); Console.WriteLine("2 - Exit the application."); Console.WriteLine("3 - Top scores"); Console.WriteLine(); input = Console.ReadLine(); intInput = int.Parse(input); if (intInput == 1) { goto start; } else if (intInput == 2) { goto fin; } else if (intInput == 3) { array1 = array1.saveInArray; goto retry; } Now, in the last 'else if' statement in the code, you can see my variable array1 trying to call the method, but no matter what I do I keep getting errors. This is the only error I have at the moment, but I have a feeling soon as I resolve that error, another will come up. For now i'm just determined to get past this error: 'int' does not contain a definition for 'saveInArray' and no extension method 'saveInArray' accepting a first argument of type 'int' could be found (are you missing a using directive or an assembly reference?). Any help would be kindly appreciated, apologies in advanced for my ugly written code! And thank you to any help that I receive! Regards, Omar.

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  • What does Ruby have that Python doesn't, and vice versa?

    - by Lennart Regebro
    There is a lot of discussions of Python vs Ruby, and I all find them completely unhelpful, because they all turn around why feature X sucks in language Y, or that claim language Y doesn't have X, although in fact it does. I also know exactly why I prefer Python, but that's also subjective, and wouldn't help anybody choosing, as they might not have the same tastes in development as I do. It would therefore be interesting to list the differences, objectively. So no "Python's lambdas sucks". Instead explain what Ruby's lambdas can do that Python's can't. No subjectivity. Example code is good! Don't have several differences in one answer, please. And vote up the ones you know are correct, and down those you know are incorrect (or are subjective). Also, differences in syntax is not interesting. We know Python does with indentation what Ruby does with brackets and ends, and that @ is called self in Python. UPDATE: This is now a community wiki, so we can add the big differences here. Ruby has a class reference in the class body In Ruby you have a reference to the class (self) already in the class body. In Python you don't have a reference to the class until after the class construction is finished. An example: class Kaka puts self end self in this case is the class, and this code would print out "Kaka". There is no way to print out the class name or in other ways access the class from the class definition body in Python. All classes are mutable in Ruby This lets you develop extensions to core classes. Here's an example of a rails extension: class String def starts_with?(other) head = self[0, other.length] head == other end end Ruby has Perl-like scripting features Ruby has first class regexps, $-variables, the awk/perl line by line input loop and other features that make it more suited to writing small shell scripts that munge text files or act as glue code for other programs. Ruby has first class continuations Thanks to the callcc statement. In Python you can create continuations by various techniques, but there is no support built in to the language. Ruby has blocks With the "do" statement you can create a multi-line anonymous function in Ruby, which will be passed in as an argument into the method in front of do, and called from there. In Python you would instead do this either by passing a method or with generators. Ruby: amethod { |here| many=lines+of+code goes(here) } Python: def function(here): many=lines+of+code goes(here) amethod(function) Interestingly, the convenience statement in Ruby for calling a block is called "yield", which in Python will create a generator. Ruby: def themethod yield 5 end themethod do |foo| puts foo end Python: def themethod(): yield 5 for foo in themethod: print foo Although the principles are different, the result is strikingly similar. Python has built-in generators (which are used like Ruby blocks, as noted above) Python has support for generators in the language. In Ruby you could use the generator module that uses continuations to create a generator from a block. Or, you could just use a block/proc/lambda! Moreover, in Ruby 1.9 Fibers are, and can be used as, generators. docs.python.org has this generator example: def reverse(data): for index in range(len(data)-1, -1, -1): yield data[index] Contrast this with the above block examples. Python has flexible name space handling In Ruby, when you import a file with require, all the things defined in that file will end up in your global namespace. This causes namespace pollution. The solution to that is Rubys modules. But if you create a namespace with a module, then you have to use that namespace to access the contained classes. In Python, the file is a module, and you can import its contained names with from themodule import *, thereby polluting the namespace if you want. But you can also import just selected names with from themodule import aname, another or you can simply import themodule and then access the names with themodule.aname. If you want more levels in your namespace you can have packages, which are directories with modules and an __init__.py file. Python has docstrings Docstrings are strings that are attached to modules, functions and methods and can be introspected at runtime. This helps for creating such things as the help command and automatic documentation. def frobnicate(bar): """frobnicate takes a bar and frobnicates it >>> bar = Bar() >>> bar.is_frobnicated() False >>> frobnicate(bar) >>> bar.is_frobnicated() True """ Python has more libraries Python has a vast amount of available modules and bindings for libraries. Python has multiple inheritance Ruby does not ("on purpose" -- see Ruby's website, see here how it's done in Ruby). It does reuse the module concept as a sort of abstract classes. Python has list/dict comprehensions Python: res = [x*x for x in range(1, 10)] Ruby: res = (0..9).map { |x| x * x } Python: >>> (x*x for x in range(10)) <generator object <genexpr> at 0xb7c1ccd4> >>> list(_) [0, 1, 4, 9, 16, 25, 36, 49, 64, 81] Ruby: p = proc { |x| x * x } (0..9).map(&p) Python: >>> {x:str(y*y) for x,y in {1:2, 3:4}.items()} {1: '4', 3: '16'} Ruby: >> Hash[{1=>2, 3=>4}.map{|x,y| [x,(y*y).to_s]}] => {1=>"4", 3=>"16"} Python has decorators Things similar to decorators can be created in Ruby, and it can also be argued that they aren't as necessary as in Python.

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  • datatables-multi-filter-select

    - by user1871603
    I am using the jquery plug-in datatables. I am using the feature, datatables-multi-filter-select on my website with php code. I want to move the drop down filter from the footer to the header like in the following example: http://www.datatables.net/extras/thirdparty/ColumnFilterWidgets/DataTables/extras/ColumnFilterWidgets/ Can anyone please update the following PHP code sample to accomplish this? Code: /** * Register necessary Plugin Filters */add_filter( 'tablepress_shortcode_table_default_shortcode_atts', 'tablepress_add_shortcode_parameters_multi_filter_select' );add_filter( 'tablepress_table_render_options', 'tablepress_set_table_foot_option', 10, 2 );add_filter( 'tablepress_table_js_options', 'tablepress_add_multi_filter_select_js_options', 10, 3 );add_filter( 'tablepress_datatables_command', 'tablepress_add_multi_filter_select_js_command', 10, 5 ); /** * Add "datatables_multi_filter_select" as a valid parameter to the [table /] Shortcode */function tablepress_add_shortcode_parameters_multi_filter_select( $default_atts ) { $default_atts['datatables_multi_filter_select'] = false; return $default_atts;} /** * Make sure that "table_foot" and "datatables_scrollX" are false, if "datatables_multi_filter_select" is true, * as the footer will be appended by the JS. Scrolling will not work with automatically added content */function tablepress_set_table_foot_option( $render_options, $table ) { if ( $render_options['datatables_multi_filter_select'] ) { $render_options['table_foot'] = false; $render_options['datatables_scrollX'] = false; } return $render_options;} /** * Pass "datatables_multi_filter_select" from Shortcode parameters to JavaScript arguments */function tablepress_add_multi_filter_select_js_options( $js_options, $table_id, $render_options ) { $js_options['datatables_multi_filter_select'] = $render_options['datatables_multi_filter_select']; // register the JS if ( $js_options['datatables_multi_filter_select'] ) { $suffix = ( defined( 'SCRIPT_DEBUG' ) && SCRIPT_DEBUG ) ? '' : '.min'; $js_multi_filter_select_url = plugins_url( "multi-filter-select{$suffix}.js", __FILE__ ); wp_enqueue_script( 'tablepress-multi_filter_select', $js_multi_filter_select_url, array( 'tablepress-datatables' ), '1.0', true ); } return $js_options;} /** * Evaluate "datatables_multi_filter_select" parameter and add corresponding JavaScript code, if needed */function tablepress_add_multi_filter_select_js_command( $command, $html_id, $parameters, $table_id, $js_options ) { if ( ! $js_options['datatables_multi_filter_select'] ) return $command; $name = str_replace( '-', '_', $html_id ); $datatables_name = "DT_{$name}"; $command = <<<JSvar {$name} = $('#{$html_id}'), {$datatables_name} = {$name}.dataTable({$parameters}), {$name}_tfoot, {$name}_selects, ths = '<tfoot>';{$name}.find('thead th').each( function( i ) { ths += '<th>' + datatables_fnCreateSelect( {$datatables_name}.fnGetColumnData(i) ) + '</th>';} );ths += '</tfoot>';{$name}_tfoot = {$name}.append(ths).find('tfoot');{$name}_selects = {$name}_tfoot.find('select');{$name}_tfoot.on( 'change', 'select', function() { {$datatables_name}.fnFilter( $(this).val(), {$name}_selects.index(this) );} );JS; return $command;} (function($) {/* * Function: fnGetColumnData * Purpose: Return an array of table values from a particular column. * Returns: array string: 1d data array * Inputs: object:oSettings - dataTable settings object. This is always the last argument past to the function * int:iColumn - the id of the column to extract the data from * bool:bUnique - optional - if set to false duplicated values are not filtered out * bool:bFiltered - optional - if set to false all the table data is used (not only the filtered) * bool:bIgnoreEmpty - optional - if set to false empty values are not filtered from the result array * Author: Benedikt Forchhammer <b.forchhammer /AT\ mind2.de> */$.fn.dataTableExt.oApi.fnGetColumnData = function ( oSettings, iColumn, bUnique, bFiltered, bIgnoreEmpty ) { // check that we have a column id if ( typeof iColumn == "undefined" ) return new Array(); // by default we only wany unique data if ( typeof bUnique == "undefined" ) bUnique = true; // by default we do want to only look at filtered data if ( typeof bFiltered == "undefined" ) bFiltered = true; // by default we do not wany to include empty values if ( typeof bIgnoreEmpty == "undefined" ) bIgnoreEmpty = true; // list of rows which we're going to loop through var aiRows; // use only filtered rows if (bFiltered == true) aiRows = oSettings.aiDisplay; // use all rows else aiRows = oSettings.aiDisplayMaster; // all row numbers // set up data array var asResultData = new Array(); for (var i=0,c=aiRows.length; i<c; i++) { iRow = aiRows[i]; var aData = this.fnGetData(iRow); var sValue = aData[iColumn]; // ignore empty values? if (bIgnoreEmpty == true && sValue.length == 0) continue; // ignore unique values? else if (bUnique == true && jQuery.inArray(sValue, asResultData) > -1) continue; // else push the value onto the result data array else asResultData.push(sValue); } return asResultData;}}(jQuery)); function datatables_fnCreateSelect( aData ) { var r = '<select><option value=""></option>', i, iLen = aData.length; for ( i=0 ; i<iLen ; i++ ) { r += '<option value="'+aData[i]+'">'+aData[i]+'</option>'; } return r + '</select>';}

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  • Making swap faster, easier to use and exception-safe

    - by FredOverflow
    I could not sleep last night and started thinking about std::swap. Here is the familiar C++98 version: template <typename T> void swap(T& a, T& b) { T c(a); a = b; b = c; } If a user-defined class Foo uses external ressources, this is inefficient. The common idiom is to provide a method void Foo::swap(Foo& other) and a specialization of std::swap<Foo>. Note that this does not work with class templates since you cannot partially specialize a function template, and overloading names in the std namespace is illegal. The solution is to write a template function in one's own namespace and rely on argument dependent lookup to find it. This depends critically on the client to follow the "using std::swap idiom" instead of calling std::swap directly. Very brittle. In C++0x, if Foo has a user-defined move constructor and a move assignment operator, providing a custom swap method and a std::swap<Foo> specialization has little to no performance benefit, because the C++0x version of std::swap uses efficient moves instead of copies: #include <utility> template <typename T> void swap(T& a, T& b) { T c(std::move(a)); a = std::move(b); b = std::move(c); } Not having to fiddle with swap anymore already takes a lot of burden away from the programmer. Current compilers do not generate move constructors and move assignment operators automatically yet, but as far as I know, this will change. The only problem left then is exception-safety, because in general, move operations are allowed to throw, and this opens up a whole can of worms. The question "What exactly is the state of a moved-from object?" complicates things further. Then I was thinking, what exactly are the semantics of std::swap in C++0x if everything goes fine? What is the state of the objects before and after the swap? Typically, swapping via move operations does not touch external resources, only the "flat" object representations themselves. So why not simply write a swap template that does exactly that: swap the object representations? #include <cstring> template <typename T> void swap(T& a, T& b) { unsigned char c[sizeof(T)]; memcpy( c, &a, sizeof(T)); memcpy(&a, &b, sizeof(T)); memcpy(&b, c, sizeof(T)); } This is as efficient as it gets: it simply blasts through raw memory. It does not require any intervention from the user: no special swap methods or move operations have to be defined. This means that it even works in C++98 (which does not have rvalue references, mind you). But even more importantly, we can now forget about the exception-safety issues, because memcpy never throws. I can see two potential problems with this approach: First, not all objects are meant to be swapped. If a class designer hides the copy constructor or the copy assignment operator, trying to swap objects of the class should fail at compile-time. We can simply introduce some dead code that checks whether copying and assignment are legal on the type: template <typename T> void swap(T& a, T& b) { if (false) // dead code, never executed { T c(a); // copy-constructible? a = b; // assignable? } unsigned char c[sizeof(T)]; std::memcpy( c, &a, sizeof(T)); std::memcpy(&a, &b, sizeof(T)); std::memcpy(&b, c, sizeof(T)); } Any decent compiler can trivially get rid of the dead code. (There are probably better ways to check the "swap conformance", but that is not the point. What matters is that it's possible). Second, some types might perform "unusual" actions in the copy constructor and copy assignment operator. For example, they might notify observers of their change. I deem this a minor issue, because such kinds of objects probably should not have provided copy operations in the first place. Please let me know what you think of this approach to swapping. Would it work in practice? Would you use it? Can you identify library types where this would break? Do you see additional problems? Discuss!

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  • Dynamic scoping in Clojure?

    - by j-g-faustus
    Hi, I'm looking for an idiomatic way to get dynamically scoped variables in Clojure (or a similar effect) for use in templates and such. Here is an example problem using a lookup table to translate tag attributes from some non-HTML format to HTML, where the table needs access to a set of variables supplied from elsewhere: (def *attr-table* ; Key: [attr-key tag-name] or [boolean-function] ; Value: [attr-key attr-value] (empty array to ignore) ; Context: Variables "tagname", "akey", "aval" '( ; translate :LINK attribute in <a> to :href [:LINK "a"] [:href aval] ; translate :LINK attribute in <img> to :src [:LINK "img"] [:src aval] ; throw exception if :LINK attribute in any other tag [:LINK] (throw (RuntimeException. (str "No match for " tagname))) ; ... more rules ; ignore string keys, used for internal bookkeeping [(string? akey)] [] )) ; ignore I want to be able to evaluate the rules (left hand side) as well as the result (right hand side), and need some way to put the variables in scope at the location where the table is evaluated. I also want to keep the lookup and evaluation logic independent of any particular table or set of variables. I suppose there are similar issues involved in templates (for example for dynamic HTML), where you don't want to rewrite the template processing logic every time someone puts a new variable in a template. Here is one approach using global variables and bindings. I have included some logic for the table lookup: ;; Generic code, works with any table on the same format. (defn rule-match? [rule-val test-val] "true if a single rule matches a single argument value" (cond (not (coll? rule-val)) (= rule-val test-val) ; plain value (list? rule-val) (eval rule-val) ; function call :else false )) (defn rule-lookup [test-val rule-table] "looks up rule match for test-val. Returns result or nil." (loop [rules (partition 2 rule-table)] (when-not (empty? rules) (let [[select result] (first rules)] (if (every? #(boolean %) (map rule-match? select test-val)) (eval result) ; evaluate and return result (recur (rest rules)) ))))) ;; Code specific to *attr-table* (def tagname) ; need these globals for the binding in html-attr (def akey) (def aval) (defn html-attr [tagname h-attr] "converts to html attributes" (apply hash-map (flatten (map (fn [[k v :as kv]] (binding [tagname tagname akey k aval v] (or (rule-lookup [k tagname] *attr-table*) kv))) h-attr )))) (defn test-attr [] "test conversion" (prn "a" (html-attr "a" {:LINK "www.google.com" "internal" 42 :title "A link" })) (prn "img" (html-attr "img" {:LINK "logo.png" }))) user=> (test-attr) "a" {:href "www.google.com", :title "A link"} "img" {:src "logo.png"} This is nice in that the lookup logic is independent of the table, so it can be reused with other tables and different variables. (Plus of course that the general table approach is about a quarter of the size of the code I had when I did the translations "by hand" in a giant cond.) It is not so nice in that I need to declare every variable as a global for the binding to work. Here is another approach using a "semi-macro", a function with a syntax-quoted return value, that doesn't need globals: (defn attr-table [tagname akey aval] `( [:LINK "a"] [:href ~aval] [:LINK "img"] [:src ~aval] [:LINK] (throw (RuntimeException. (str "No match for " tagname))) ; ... more rules [(string? ~akey)] [] ))) Only a couple of changes are needed to the rest of the code: In rule-match?, when syntax-quoted the function call is no longer a list: - (list? rule-val) (eval rule-val) + (seq? rule-val) (eval rule-val) In html-attr: - (binding [tagname tagname akey k aval v] - (or (rule-lookup [k tagname] *attr-table*) kv))) + (or (rule-lookup [k tagname] (attr-table tagname k v)) kv))) And we get the same result without globals. (And without dynamic scoping.) Are there other alternatives to pass along sets of variable bindings declared elsewhere, without the globals required by Clojure's binding? Is there an idiomatic way of doing it, like Ruby's binding or Javascript's function.apply(context)?

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  • ASP.net MVC 2.0 using the same form for adding and editing.

    - by Chevex
    I would like to use the same view for editing a blog post and adding a blog post. However, I'm having an issue with the ID. When adding a blog post, I have no need for an ID value to be posted. When model binding binds the form values to the BlogPost object in the controller, it will auto-generate the ID in entity framework entity. When I am editing a blog post I DO need a hidden form field to store the ID in so that it accompanies the next form post. Here is the view I have right now. <% using (Html.BeginForm("CommitEditBlogPost", "Admin")) { %> <% if (Model != null) { %> <%: Html.HiddenFor(x => x.Id)%> <% } %> Title:<br /> <%: Html.TextBoxFor(x => x.Title, new { Style = "Width: 90%;" })%> <br /> <br /> Summary:<br /> <%: Html.TextAreaFor(x => x.Summary, new { Style = "Width: 90%; Height: 50px;" }) %> <br /> <br /> Body:<br /> <%: Html.TextAreaFor(x => x.Body, new { Style = "Height: 250px; Width: 90%;" })%> <br /> <br /> <input type="submit" value="Submit" /> <% } %> Right now checking if the model is coming in NULL is a great way to know if I'm editing a blog post or adding one, because when I'm adding one it will be null as it hasn't been created yet. The problem comes in when there is an error and the entity is invalid. When the controller renders the form after an invalid model the Model != null evaluates to false, even though we are editing a post and there is clearly a model. If I render the hidden input field for ID when adding a post, I get an error stating that the ID can't be null. Any help is appreciated. EDIT: I went with OJ's answer for this question, however I discovered something that made me feel silly and I wanted to share it just in case anyone was having a similar issue. The page the adds/edits blogs does not even need a hidden field for id, ever. The reason is because when I go to add a blog I do a GET to this relative URL BlogProject/Admin/AddBlogPost This URL does not contain an ID and the action method just renders the page. The page does a POST to the same URL when adding the blog post. The incoming BlogPost entity has a null Id and is generated by EF during save changes. The same thing happens when I edit blog posts. The URL is BlogProject/Admin/EditBlogPost/{Id} This URL contains the id of the blog post and since the page is posting back to the exact same URL the id goes with the POST to the action method that executes the edit. The only problem I encountered with this is that the action methods cannot have identical signatures. [HttpGet] public ViewResult EditBlogPost(int Id) { } [HttpPost] public ViewResult EditBlogPost(int Id) { } The compiler will yell at you if you try to use these two methods above. It is far too convenient that the Id will be posted back when doing a Html.BeginForm() with no arguments for action or controller. So rather than change the name of the POST method I just modified the arguments to include a FormCollection. Like this: [HttpPost] public ViewResult EditBlogPost(int Id, FormCollection formCollection) { // You can then use formCollection as the IValueProvider for UpdateModel() // and TryUpdateModel() if you wish. I mean, you might as well use the // argument since you're taking it. } The formCollection variable is filled via model binding with the same content that Request.Form would be by default. You don't have to use this collection for UpdateModel() or TryUpdateModel() but I did just so I didn't feel like that collection was pointless since it really was just to make the method signature different from its GET counterpart. Thanks for the help guys!

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  • a program similar to ls with some modifications

    - by Bond
    Hi, here is a simple puzzle I wanted to discuss. A C program to take directory name as command line argument and print last 3 directories and 3 files in all subdirectories without using api 'system' inside it. suppose directory bond0 contains bond1, di2, bond3, bond4, bond5 and my_file1, my_file2, my_file3, my_file4, my_file5, my_file6 and bond1 contains bond6 my_file7 my_file8 my_file9 my_file10 program should output - bond3, bond4, bond5, my_file4, my_file5, my_file6, bond6, my_file8, my_file9, my_file10 My code for the above problem is here #include<dirent.h> #include<unistd.h> #include<string.h> #include<sys/stat.h> #include<stdlib.h> #include<stdio.h> char *directs[20], *files[20]; int i = 0; int j = 0; int count = 0; void printdir(char *); int count_dirs(char *); int count_files(char *); int main() { char startdir[20]; printf("Scanning user directories\n"); scanf("%s", startdir); printdir(startdir); } void printdir(char *dir) { printf("printdir called %d directory is %s\n", ++count, dir); DIR *dp = opendir(dir); int nDirs, nFiles, nD, nF; nDirs = 0; nFiles = 0; nD = 0; nF = 0; if (dp) { struct dirent *entry = 0; struct stat statBuf; nDirs = count_dirs(dir); nFiles = count_files(dir); printf("The no of subdirectories in %s is %d \n", dir, nDirs); printf("The no of files in %s is %d \n", dir, nFiles); while ((entry = readdir(dp)) != 0) { if (strcmp(entry->d_name, ".") == 0 || strcmp(entry->d_name, "..") == 0) { continue; } char *filepath = malloc(strlen(dir) + strlen(entry->d_name) + 2); if (filepath) { sprintf(filepath, "%s/%s", dir, entry->d_name); if (lstat(filepath, &statBuf) != 0) { } if (S_ISDIR(statBuf.st_mode)) { nD++; if ((nDirs - nD) < 3) { printf("The directory is %s\n",entry->d_name); } } else { nF++; if ((nFiles - nF) < 3) { printf("The files are %s\n", entry->d_name); } //if } //else free(filepath); } //if(filepath) } //while while ((entry = readdir(dp)) != 0) { if (strcmp(entry->d_name, ".") == 0 || strcmp(entry->d_name, "..") == 0) { continue; } printf("In second while loop *entry=%s\n",entry->d_name); char *filepath = malloc(strlen(dir) + strlen(entry->d_name) + 2); if (filepath) { sprintf(filepath, "%s/%s", dir, entry->d_name); if (lstat(filepath, &statBuf) != 0) { } if (S_ISDIR(statBuf.st_mode)) { printdir(entry->d_name); } } //else free(filepath); } //2nd while closedir(dp); } else { fprintf(stderr, "Error, cannot open directory %s\n", dir); } } //printdir int count_dirs(char *dir) { DIR *dp = opendir(dir); int nD; nD = 0; if (dp) { struct dirent *entry = 0; struct stat statBuf; while ((entry = readdir(dp)) != 0) { if (strcmp(entry->d_name, ".") == 0 || strcmp(entry->d_name, "..") == 0) { continue; } char *filepath = malloc(strlen(dir) + strlen(entry->d_name) + 2); if (filepath) { sprintf(filepath, "%s/%s", dir, entry->d_name); if (lstat(filepath, &statBuf) != 0) { fprintf(stderr, "File Not found? %s\n", filepath); } if (S_ISDIR(statBuf.st_mode)) { nD++; } else { continue; } free(filepath); } } closedir(dp); } else { fprintf(stderr, "Error, cannot open directory %s\n", dir); } return nD; } int count_files(char *dir) { DIR *dp = opendir(dir); int nF; nF = 0; if (dp) { struct dirent *entry = 0; struct stat statBuf; while ((entry = readdir(dp)) != 0) { if (strcmp(entry->d_name, ".") == 0 || strcmp(entry->d_name, "..") == 0) { continue; } char *filepath = malloc(strlen(dir) + strlen(entry->d_name) + 2); if (filepath) { sprintf(filepath, "%s/%s", dir, entry->d_name); if (lstat(filepath, &statBuf) != 0) { fprintf(stderr, "File Not found? %s\n", filepath); } if (S_ISDIR(statBuf.st_mode)) { continue; } else { nF++; } free(filepath); } } closedir(dp); } else { fprintf(stderr, "Error, cannot open file %s\n", dir); } return nF; } The above code I wrote is a bit not functioning correctly can some one help me to understand the error which is coming.So that I improve it further.There seems to be some small glitch which is not clear to me right now.

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  • sequential mandelbrot image creation

    - by visanio_learner
    can anyone tell me what is wrong in this code? i am getting an error in the main function, when i am calling the 'file_write' method function inside the main function, it says 'y' is not declared in this scope, but actually it was an argument that i have passed it in the method function earlier. is it a serious error? #include <stdio.h> #include <stdlib.h> #include <time.h> unsigned int width = 1500; unsigned int height = 1500; unsigned int max_iterations = 30000; unsigned int **color = NULL; double threshold = 4; double min_re = -2.0; double max_re = 1.0; double min_im = -1.2; double max_im = min_im+(max_re-min_re)*height/width; double x_factor = (max_re-min_re)/(width-1); double y_factor = (max_im-min_im)/(height-1); int file_write(int x, int y, double min_re, double max_im, double x_factor, double y_factor) { FILE *fractal = fopen("mandelbrot_imageSequential.ppm","w+"); if(fractal != NULL) { fprintf(fractal,"P6\n"); fprintf(fractal,"# %s\n", "Mandelbrot_imageSequential.ppm"); fprintf(fractal,"%d %d\n", height, width); fprintf(fractal,"255\n"); unsigned int R = 0, G = 0, B = 0; for(unsigned y = 0; y < height; ++y) { double c_im = max_im - y*y_factor; for(unsigned x = 0; x < width; ++x) { double c_re = min_re + x*x_factor; double Z_re = c_re, Z_im = c_im; bool image_inside = true; R = 0, G = 0, B = 0; for(unsigned n=0; n<max_iterations; ++n) { double Z_re2 = Z_re*Z_re, Z_im2 = Z_im*Z_im; if(Z_re2 + Z_im2 > threshold) { image_inside = false; G = n; if(G == 10) { G = 25, R = 10, B = 5; } break; } Z_im = 2 * Z_re * Z_im + c_im; Z_re = Z_re2 - Z_im2 + c_re; } if(image_inside) { putc(R, fractal); putc(G, fractal); putc(B, fractal); } else { putc(R, fractal); putc(G, fractal); putc(B, fractal); } } } fclose(fractal); return 0; } } int main(int argc, char *argv[]) { if(argc != 9) { printf("There is an error in the input given.\n"); return 0; } else { height = atoi(argv[1]); width = atoi(argv[2]); max_iterations = atoi(argv[3]); min_re = atof(argv[4]); max_re = atof(argv[5]); min_im = atof(argv[6]); max_im = atof(argv[7]); threshold = atoi(argv[8]); } color = (unsigned int**)malloc(height*sizeof(unsigned int*)); printf("height = %d\twidth = %d\tmaximum_iterations = %d\tminimum_x-value = %.2f\tmaximum_x-value = %.2f\tminimum_y-value = %.2f\tmaximum_y-value = %.2f\tthreshold_value = %.2f\t\n",height,width,max_iterations,min_re,max_re,min_im,max_im,threshold); int x; for(x = 0; x < height; x++) { color[x] = (unsigned int*)malloc(width*sizeof(unsigned int)); } time_t ts,te; time(&ts); file_write(x,y,min_re,max_im,x_factor,y_factor); time(&te); double diff = difftime(te,ts); printf("Total Time elapsed: %f\n",diff); for(x = 0; x < height; x++) { free(color[x]); } free(color); return 0; }

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  • Using Array Variables For FILE_GET_CONTENTS

    - by Whoshooter
    I have a script all done now and everything has been debugged and it works, except for the last hurdle. This script grabs pertinent information on bank web sites, takes that data and uses it to populate a template and then it's all posted to Wordpress - BUT I get an error because the file_get_contents function fails taking each url from the Array. I've var_dumped the array and all the URLS are there in the [0] key, so this is what I tried. master data is the scraped URL source the script uses urlscrape_array is the collection of URLS $master_data = file_get_contents($urlscrape_array[0]); When I run the script using a URL like below it works beautifully every time; $master_data = file_get_contents("http://www.somesite/somepage.html"); This is the error I get when I try to use the first example' Warning: file_get_contents() expects parameter 1 to be string, array given in /home3/path/public_html/mysite.com/boise_project/scriptmainpage.php on line 13 As requested here is a sample of the var_dump on $urlscrape_array[0] array(504) { [0]=> string(56) "http://www.somepage.com/somepage-3178.html" [1]=> string(54) "http://www.somepage.com/somepage-16.html" [2]=> string(56) "http://www.somepage.com/somepage-3202.html" [3]=> string(56) "http://www.somepage.com/somepage-4324.html" [4]=> string(56) "http://www.somepage.com/somepage-4777.html" [5]=> string(56) "http://www.somepage.com/somepage-5140.html" [6]=> string(56) "http://www.somepage.com/somepage-5220.html" [7]=> string(56) "http://www.somepage.com/somepage-9205.html" [8]=> string(56) "http://www.somepage.com/somepage-3251.html" [9]=> string(56) "http://www.somepage.com/somepage-3323.html" [10]=> string(56) "http://www.somepage.com/some-page-3797.html" [11]=> string(56) "http://www.somepage.com/some-page-4145.html" [12]=> string(56) "http://www.somepage.com/some-page-3191.html" [13]=> string(55) "http://www.somepage.com/some-page-329.html" [14]=> string(56) etc.... Error as per the foreach statement provided by Uptown Warning: Invalid argument supplied for foreach() in /home3/bettyt45/public_html/bdbud.com/boise_project/boise-wordpress.php on line 12 NULL print_r resulst below; Array ( [0] => Array ( [0] => http://www.somesite.com/some-page-3178.html [1] => http://www.somesite.com/some-page-16.html [2] => http://www.somesite.com/some-page-3202.html [3] => http://www.somesite.com/some-page-4324.html [4] => http://www.somesite.com/some-page-4777.html [5] => http://www.somesite.com/some-page-5140.html [6] => http://www.somesite.com/some-page-5220.html [7] => http://www.somesite.com/some-page-9205.html [8] => http://www.somesite.com/some-page-3251.html [9] => http://www.somesite.com/some-page-3323.html [10] => http://www.somesite.com/some-page-3797.html [11] => http://www.somesite.com/some-page-4145.html [12] => http://www.somesite.com/some-page-3191.html [13] => http://www.somesite.com/some-page-329.html [14] => http://www.somesite.com/some-page-3341.html [15] => http://www.somesite.com/some-page-3758.html [16] => http://www.somesite.com/some-page-4180.html [17] => http://www.somesite.com/some-page-9014.html [18] => http://www.somesite.com/some-page-5987.html [19] => http://www.somesite.com/some-page-1542.html [20] => http://www.somesite.com/some-page-3004.html [21] => http://www.somesite.com/some-page-9034.html [22] => http://www.somesite.com/some-page-3385.html [23] => http://www.somesite.com/some-page-3435.html [24] => http://www.somesite.com/some-page-6389.html [25] => http://www.somesite.com/some-page-6992.html [26] => http://www.somesite.com/some-page-7051.html HERE IS THE CODE I USED TO CREATE THE ARRAY ABOVE; $urlscrape_data = file_get_contents('http://www.bdbud.com/boise_project/boise-urls.htm'); preg_match_all('~http\:\/\/www.creditunionsonline.com\/credit\-union\-\d{1,4}?\.html~', $urlscrape_data, $urlscrape_matches); $urlscrape_array = $urlscrape_matches;

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  • How to make negate_unary work with any type?

    - by Chan
    Hi, Following this question: How to negate a predicate function using operator ! in C++? I want to create an operator ! can work with any functor that inherited from unary_function. I tried: template<typename T> inline std::unary_negate<T> operator !( const T& pred ) { return std::not1( pred ); } The compiler complained: Error 5 error C2955: 'std::unary_function' : use of class template requires template argument list c:\program files\microsoft visual studio 10.0\vc\include\xfunctional 223 1 Graphic Error 7 error C2451: conditional expression of type 'std::unary_negate<_Fn1>' is illegal c:\program files\microsoft visual studio 10.0\vc\include\ostream 529 1 Graphic Error 3 error C2146: syntax error : missing ',' before identifier 'argument_type' c:\program files\microsoft visual studio 10.0\vc\include\xfunctional 222 1 Graphic Error 4 error C2065: 'argument_type' : undeclared identifier c:\program files\microsoft visual studio 10.0\vc\include\xfunctional 222 1 Graphic Error 2 error C2039: 'argument_type' : is not a member of 'std::basic_ostream<_Elem,_Traits>::sentry' c:\program files\microsoft visual studio 10.0\vc\include\xfunctional 222 1 Graphic Error 6 error C2039: 'argument_type' : is not a member of 'std::basic_ostream<_Elem,_Traits>::sentry' c:\program files\microsoft visual studio 10.0\vc\include\xfunctional 230 1 Graphic Any idea? Update Follow "templatetypedef" solution, I got new error: Error 3 error C2831: 'operator !' cannot have default parameters c:\visual studio 2010 projects\graphic\graphic\main.cpp 39 1 Graphic Error 2 error C2808: unary 'operator !' has too many formal parameters c:\visual studio 2010 projects\graphic\graphic\main.cpp 39 1 Graphic Error 4 error C2675: unary '!' : 'is_prime' does not define this operator or a conversion to a type acceptable to the predefined operator c:\visual studio 2010 projects\graphic\graphic\main.cpp 52 1 Graphic Update 1 Complete code: #include <iostream> #include <functional> #include <utility> #include <cmath> #include <algorithm> #include <iterator> #include <string> #include <boost/assign.hpp> #include <boost/assign/std/vector.hpp> #include <boost/assign/std/map.hpp> #include <boost/assign/std/set.hpp> #include <boost/assign/std/list.hpp> #include <boost/assign/std/stack.hpp> #include <boost/assign/std/deque.hpp> struct is_prime : std::unary_function<int, bool> { bool operator()( int n ) const { if( n < 2 ) return 0; if( n == 2 || n == 3 ) return 1; if( n % 2 == 0 || n % 3 == 0 ) return 0; int upper_bound = std::sqrt( static_cast<double>( n ) ); for( int pf = 5, step = 2; pf <= upper_bound; ) { if( n % pf == 0 ) return 0; pf += step; step = 6 - step; } return 1; } }; /* template<typename T> inline std::unary_negate<T> operator !( const T& pred, typename T::argument_type* dummy = 0 ) { return std::not1<T>( pred ); } */ inline std::unary_negate<is_prime> operator !( const is_prime& pred ) { return std::not1( pred ); } template<typename T> inline void print_con( const T& con, const std::string& ms = "", const std::string& sep = ", " ) { std::cout << ms << '\n'; std::copy( con.begin(), con.end(), std::ostream_iterator<typename T::value_type>( std::cout, sep.c_str() ) ); std::cout << "\n\n"; } int main() { using namespace boost::assign; std::vector<int> nums; nums += 1, 3, 5, 7, 9; nums.erase( remove_if( nums.begin(), nums.end(), !is_prime() ), nums.end() ); print_con( nums, "After remove all primes" ); } Thanks, Chan Nguyen

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  • Multiple (variant) arguments overloading in Java: What's the purpose?

    - by fortran
    Browsing google's guava collect library code, I've found the following: // Casting to any type is safe because the list will never hold any elements. @SuppressWarnings("unchecked") public static <E> ImmutableList<E> of() { return (ImmutableList<E>) EmptyImmutableList.INSTANCE; } public static <E> ImmutableList<E> of(E element) { return new SingletonImmutableList<E>(element); } public static <E> ImmutableList<E> of(E e1, E e2) { return new RegularImmutableList<E>( ImmutableList.<E>nullCheckedList(e1, e2)); } public static <E> ImmutableList<E> of(E e1, E e2, E e3) { return new RegularImmutableList<E>( ImmutableList.<E>nullCheckedList(e1, e2, e3)); } public static <E> ImmutableList<E> of(E e1, E e2, E e3, E e4) { return new RegularImmutableList<E>( ImmutableList.<E>nullCheckedList(e1, e2, e3, e4)); } public static <E> ImmutableList<E> of(E e1, E e2, E e3, E e4, E e5) { return new RegularImmutableList<E>( ImmutableList.<E>nullCheckedList(e1, e2, e3, e4, e5)); } public static <E> ImmutableList<E> of(E e1, E e2, E e3, E e4, E e5, E e6) { return new RegularImmutableList<E>( ImmutableList.<E>nullCheckedList(e1, e2, e3, e4, e5, e6)); } public static <E> ImmutableList<E> of( E e1, E e2, E e3, E e4, E e5, E e6, E e7) { return new RegularImmutableList<E>( ImmutableList.<E>nullCheckedList(e1, e2, e3, e4, e5, e6, e7)); } public static <E> ImmutableList<E> of( E e1, E e2, E e3, E e4, E e5, E e6, E e7, E e8) { return new RegularImmutableList<E>( ImmutableList.<E>nullCheckedList(e1, e2, e3, e4, e5, e6, e7, e8)); } public static <E> ImmutableList<E> of( E e1, E e2, E e3, E e4, E e5, E e6, E e7, E e8, E e9) { return new RegularImmutableList<E>( ImmutableList.<E>nullCheckedList(e1, e2, e3, e4, e5, e6, e7, e8, e9)); } public static <E> ImmutableList<E> of( E e1, E e2, E e3, E e4, E e5, E e6, E e7, E e8, E e9, E e10) { return new RegularImmutableList<E>(ImmutableList.<E>nullCheckedList( e1, e2, e3, e4, e5, e6, e7, e8, e9, e10)); } public static <E> ImmutableList<E> of( E e1, E e2, E e3, E e4, E e5, E e6, E e7, E e8, E e9, E e10, E e11) { return new RegularImmutableList<E>(ImmutableList.<E>nullCheckedList( e1, e2, e3, e4, e5, e6, e7, e8, e9, e10, e11)); } public static <E> ImmutableList<E> of( E e1, E e2, E e3, E e4, E e5, E e6, E e7, E e8, E e9, E e10, E e11, E e12, E... others) { final int paramCount = 12; Object[] array = new Object[paramCount + others.length]; arrayCopy(array, 0, e1, e2, e3, e4, e5, e6, e7, e8, e9, e10, e11, e12); arrayCopy(array, paramCount, others); return new RegularImmutableList<E>(ImmutableList.<E>nullCheckedList(array)); } And although it seems reasonable to have overloads for empty and single arguments (as they are going to use special instances), I cannot see the reason behind having all the others, when just the last one (with two fixed arguments plus the variable argument instead the dozen) seems to be enough. As I'm writing, one explanation that pops into my head is that the API pre-dates Java 1.5; and although the signatures would be source-level compatible, the binary interface would differ. Isn't it?

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  • Preventing FIN_WAIT2 when closing socket

    - by patrickvacek
    I have a server program that connects to another program via a given socket, and in certain cases I need to close the connection and almost immediately re-open it on the same socket. This by and large works, except that I have to wait exactly one minute for the socket to reset. In the meantime, netstat indicates that the server sees the socket in FIN_WAIT2 and the client sees it as CLOSE_WAIT. I'm already using SO_REUSEADDR, which I thought would prevent the wait, but that isn't doing the trick. Setting SO_LINGER to zero also does not help. What else can I do to resolve this? Here are the relevant code snippets: SetUpSocket() { // Set up the socket and listen for a connection from the exelerate client. // Open a TCP/IP socket. m_baseSock = socket(PF_INET, SOCK_STREAM, IPPROTO_IP); if (m_baseSock < 0) { return XERROR; } // Set the socket options to reuse local addresses. int flag = 1; if (setsockopt(m_baseSock, SOL_SOCKET, SO_REUSEADDR, &flag, sizeof(flag)) == -1) { return XERROR; } // Set the socket options to prevent lingering after closing the socket. //~ linger li = {1,0}; //~ if (setsockopt(m_baseSock, SOL_SOCKET, SO_LINGER, &li, sizeof(li)) == -1) //~ { //~ return XERROR; //~ } // Bind the socket to the address of the current host and our given port. struct sockaddr_in addr; memset(&addr, 0, sizeof(addr)); addr.sin_family = AF_INET; addr.sin_addr.s_addr = INADDR_ANY; addr.sin_port = htons(m_port); if (bind(m_baseSock, (struct sockaddr*)&addr, sizeof(addr)) != 0) { return XERROR; } // Tell the socket to listen for a connection from client. if (listen(m_baseSock, 4) != 0) { return XERROR; } return XSUCCESS; } ConnectSocket() { // Add the socket to a file descriptor set. fd_set readfds; FD_ZERO(&readfds); FD_SET(m_baseSock, &readfds); // Set timeout to ten seconds. Plenty of time. struct timeval timeout; timeout.tv_sec = 10; timeout.tv_usec = 0; // Check to see if the socket is ready for reading. int numReady = select(m_baseSock + 1, &readfds, NULL, NULL, &timeout); if (numReady > 0) { int flags = fcntl(m_baseSock, F_GETFL, 0); fcntl(m_baseSock, flags | O_NONBLOCK, 1); // Wait for a connection attempt from the client. Do not block - we shouldn't // need to since we just selected. m_connectedSock = accept(m_baseSock, NULL, NULL); if (m_connectedSock > 0) { m_failedSend = false; m_logout = false; // Spawn a thread to accept commands from client. CreateThread(&m_controlThread, ControlThread, (void *)&m_connectedSock); return XSUCCESS; } } return XERROR; } ControlThread(void *arg) { // Get the socket from the argument. socket sock = *((socket*)arg); while (true) { // Add the socket to a file descriptor set. fd_set readfds; FD_ZERO(&readfds); FD_SET(sock, &readfds); // Set timeout to ten seconds. Plenty of time. struct timeval timeout; timeout.tv_sec = 10; timeout.tv_usec = 0; // Check if there is any readable data on the socket. int num_ready = select(sock + 1, &readfds, NULL, NULL, &timeout); if (num_ready < 0) { return NULL; } // If there is data, read it. else if (num_ready > 0) { // Check the read buffer. xuint8 buf[128]; ssize_t size_read = recv(sock, buf, sizeof(buf)); if (size_read > 0) { // Get the message out of the buffer. char msg = *buf; if (msg == CONNECTED) { // Do some things... } // If we get the log-out message, log out. else if (msg == LOGOUT) { return NULL; } } } } // while return NULL; } ~Server() { // Close the sockets. if (m_baseSock != SOCKET_ERROR) { close(m_baseSock); m_baseSock = SOCKET_ERROR; } if (m_connectedSock != SOCKET_ERROR) { close(m_connectedSock); m_connectedSock = SOCKET_ERROR; } } SOCKET_ERROR is equal to -1. The server object gets destroyed, at which point the connection should close, and then recreated, at which point the SetUpSocket() and ConnectSocket() routines are called. So why do I have to wait a minute for the socket to clear? Any ideas would be appreaciated.

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  • How do I make my applet turn the user's input into an integer and compare it to the computer's random number?

    - by Kitteran
    I'm in beginning programming and I don't fully understand applets yet. However, (with some help from internet tutorials) I was able to create an applet that plays a game of guess with the user. The applet compiles fine, but when it runs, this error message appears: "Exception in thread "main" java.lang.NumberFormatException: For input string: "" at java.lang.NumberFormatException.forInputString(NumberFormatException.java:48) at java.lang.Integer.parseInt(Integer.java:470) at java.lang.Integer.parseInt(Integer.java:499) at Guess.createUserInterface(Guess.java:101) at Guess.<init>(Guess.java:31) at Guess.main(Guess.java:129)" I've tried moving the "userguess = Integer.parseInt( t1.getText() );" on line 101 to multiple places, but I still get the same error. Can anyone tell me what I'm doing wrong? The Code: // Creates the game GUI. import javax.swing.*; import java.awt.*; import java.awt.event.*; public class Guess extends JFrame{ private JLabel userinputJLabel; private JLabel lowerboundsJLabel; private JLabel upperboundsJLabel; private JLabel computertalkJLabel; private JButton guessJButton; private JPanel guessJPanel; static int computernum; int userguess; static void declare() { computernum = (int) (100 * Math.random()) + 1; //random number picked (1-100) } // no-argument constructor public Guess() { createUserInterface(); } // create and position GUI components private void createUserInterface() { // get content pane and set its layout Container contentPane = getContentPane(); contentPane.setLayout( null ); contentPane.setBackground( Color.white ); // set up userinputJLabel userinputJLabel = new JLabel(); userinputJLabel.setText( "Enter Guess Here -->" ); userinputJLabel.setBounds( 0, 65, 120, 50 ); userinputJLabel.setHorizontalAlignment( JLabel.CENTER ); userinputJLabel.setBackground( Color.white ); userinputJLabel.setOpaque( true ); contentPane.add( userinputJLabel ); // set up lowerboundsJLabel lowerboundsJLabel = new JLabel(); lowerboundsJLabel.setText( "Lower Bounds Of Guess = 1" ); lowerboundsJLabel.setBounds( 0, 0, 170, 50 ); lowerboundsJLabel.setHorizontalAlignment( JLabel.CENTER ); lowerboundsJLabel.setBackground( Color.white ); lowerboundsJLabel.setOpaque( true ); contentPane.add( lowerboundsJLabel ); // set up upperboundsJLabel upperboundsJLabel = new JLabel(); upperboundsJLabel.setText( "Upper Bounds Of Guess = 100" ); upperboundsJLabel.setBounds( 250, 0, 170, 50 ); upperboundsJLabel.setHorizontalAlignment( JLabel.CENTER ); upperboundsJLabel.setBackground( Color.white ); upperboundsJLabel.setOpaque( true ); contentPane.add( upperboundsJLabel ); // set up computertalkJLabel computertalkJLabel = new JLabel(); computertalkJLabel.setText( "Computer Says:" ); computertalkJLabel.setBounds( 0, 130, 100, 50 ); //format (x, y, width, height) computertalkJLabel.setHorizontalAlignment( JLabel.CENTER ); computertalkJLabel.setBackground( Color.white ); computertalkJLabel.setOpaque( true ); contentPane.add( computertalkJLabel ); //Set up guess jbutton guessJButton = new JButton(); guessJButton.setText( "Enter" ); guessJButton.setBounds( 250, 78, 100, 30 ); contentPane.add( guessJButton ); guessJButton.addActionListener( new ActionListener() // anonymous inner class { // event handler called when Guess button is pressed public void actionPerformed( ActionEvent event ) { guessActionPerformed( event ); } } // end anonymous inner class ); // end call to addActionListener // set properties of application's window setTitle( "Guess Game" ); // set title bar text setSize( 500, 500 ); // set window size setVisible( true ); // display window //create text field TextField t1 = new TextField(); // Blank text field for user input t1.setBounds( 135, 78, 100, 30 ); contentPane.add( t1 ); userguess = Integer.parseInt( t1.getText() ); //create section for computertalk Label computertalkLabel = new Label(""); computertalkLabel.setBounds( 115, 130, 300, 50); contentPane.add( computertalkLabel ); } // Display computer reactions to user guess private void guessActionPerformed( ActionEvent event ) { if (userguess > computernum) //if statements (computer's reactions to user guess) computertalkJLabel.setText( "Computer Says: Too High" ); else if (userguess < computernum) computertalkJLabel.setText( "Computer Says: Too Low" ); else if (userguess == computernum) computertalkJLabel.setText( "Computer Says:You Win!" ); else computertalkJLabel.setText( "Computer Says: Error" ); } // end method oneJButtonActionPerformed // end method createUserInterface // main method public static void main( String args[] ) { Guess application = new Guess(); application.setDefaultCloseOperation (JFrame.EXIT_ON_CLOSE); } // end method main } // end class Phone

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  • Java error starting with "log4j:WARN No appenders could be found for logger" in ZuckerReports SugarC

    - by Tom McDonnell
    Greetings all. I apologise for posting this problem here, but I do so in desperation after receiving no response on the SugarCRM forums. Even if a reader is unfamiliar with ZuckerReports or SugarCRM some general advice on Java may be of use to me. I have installed ZuckerReports v1.12 in SugarCRM 5.5.1. When I attempt to run a report I get the following error message. cmdline: javaw -classpath "custom/ZuckerReports/resources/;custom/ZuckerReports/resources/contact_counts_by_first_name.jasper_files/;modules/ZuckerReports/jasper/ant-1.7.1.jar;modules/ZuckerReports/jasper/antlr-2.7.6.jar;modules/ZuckerReports/jasper/asm-attrs.jar;modules/ZuckerReports/jasper/asm.jar;modules/ZuckerReports/jasper/barbecue-1.5-beta1.jar;modules/ZuckerReports/jasper/barcode4j-2.0.jar;modules/ZuckerReports/jasper/batik-anim.jar;modules/ZuckerReports/jasper/batik-awt-util.jar;modules/ZuckerReports/jasper/batik-bridge.jar;modules/ZuckerReports/jasper/batik-css.jar;modules/ZuckerReports/jasper/batik-dom.jar;modules/ZuckerReports/jasper/batik-ext.jar;modules/ZuckerReports/jasper/batik-gvt.jar;modules/ZuckerReports/jasper/batik-parser.jar;modules/ZuckerReports/jasper/batik-script.jar;modules/ZuckerReports/jasper/batik-svg-dom.jar;modules/ZuckerReports/jasper/batik-svggen.jar;modules/ZuckerReports/jasper/batik-util.jar;modules/ZuckerReports/jasper/batik-xml.jar;modules/ZuckerReports/jasper/bcel-5.2.jar;modules/ZuckerReports/jasper/bsh-2.0b4.jar;modules/ZuckerReports/jasper/castor-1.2.jar;modules/ZuckerReports/jasper/cglib-2.1.jar;modules/ZuckerReports/jasper/cincom-jr-xmla.jar;modules/ZuckerReports/jasper/commons-beanutils-1.8.2.jar;modules/ZuckerReports/jasper/commons-collections-3.2.1.jar;modules/ZuckerReports/jasper/commons-dbcp-1.2.2.jar;modules/ZuckerReports/jasper/commons-digester-1.7.jar;modules/ZuckerReports/jasper/commons-javaflow-20060411.jar;modules/ZuckerReports/jasper/commons-logging-1.1.jar;modules/ZuckerReports/jasper/commons-math-1.0.jar;modules/ZuckerReports/jasper/commons-pool-1.3.jar;modules/ZuckerReports/jasper/commons-vfs-1.0.jar;modules/ZuckerReports/jasper/dom4j-1.6.jar;modules/ZuckerReports/jasper/ehcache-1.1.jar;modules/ZuckerReports/jasper/eigenbase-properties-1.1.0.10924.jar;modules/ZuckerReports/jasper/eigenbase-resgen-1.3.0.11873.jar;modules/ZuckerReports/jasper/eigenbase-xom-1.3.0.11999.jar;modules/ZuckerReports/jasper/ejb3-persistence.jar;modules/ZuckerReports/jasper/groovy-all-1.5.5.jar;modules/ZuckerReports/jasper/hibernate-annotations.jar;modules/ZuckerReports/jasper/hibernate-commons-annotations.jar;modules/ZuckerReports/jasper/hibernate3.jar;modules/ZuckerReports/jasper/hsqldb-1.8.0-10.jar;modules/ZuckerReports/jasper/iText-2.1.0.jar;modules/ZuckerReports/jasper/iTextAsian.jar;modules/ZuckerReports/jasper/jakarta-bcel-20050813.jar;modules/ZuckerReports/jasper/jasperreports-3.7.1.jar;modules/ZuckerReports/jasper/jasperreports-chart-themes-3.6.2.jar;modules/ZuckerReports/jasper/jasperreports-extensions-3.5.3.jar;modules/ZuckerReports/jasper/jasperreports-fonts-3.6.1.jar;modules/ZuckerReports/jasper/javacup.jar;modules/ZuckerReports/jasper/javassist-3.4.GA.jar;modules/ZuckerReports/jasper/jaxen-1.1.1.jar;modules/ZuckerReports/jasper/jcommon-1.0.15.jar;modules/ZuckerReports/jasper/jdt-compiler-3.1.1.jar;modules/ZuckerReports/jasper/jfreechart-1.0.12.jar;modules/ZuckerReports/jasper/jpa.jar;modules/ZuckerReports/jasper/js_activation-1.1.jar;modules/ZuckerReports/jasper/js_axis-1.4patched.jar;modules/ZuckerReports/jasper/js_commons-codec-1.3.jar;modules/ZuckerReports/jasper/js_commons-discovery-0.2.jar;modules/ZuckerReports/jasper/js_commons-httpclient-3.1.jar;modules/ZuckerReports/jasper/js_jasperserver-common-ws-3.5.0.jar;modules/ZuckerReports/jasper/js_jaxrpc.jar;modules/ZuckerReports/jasper/js_mail-1.4.jar;modules/ZuckerReports/jasper/js_saaj-api-1.3.jar;modules/ZuckerReports/jasper/js_wsdl4j-1.5.1.jar;modules/ZuckerReports/jasper/jta.jar;modules/ZuckerReports/jasper/jxl-2.6.jar;modules/ZuckerReports/jasper/log4j-1.2.15.jar;modules/ZuckerReports/jasper/mondrian-3.1.1.12687-Jaspersoft.jar;modules/ZuckerReports/jasper/mysql-connector-java-3.1.11-bin.jar;modules/ZuckerReports/jasper/olap4j-0.9.7.145.jar;modules/ZuckerReports/jasper/png-encoder-1.5.jar;modules/ZuckerReports/jasper/poi-3.2-FINAL-20081019.jar;modules/ZuckerReports/jasper/rex-20080421.jar;modules/ZuckerReports/jasper/rhino-1.7R1.jar;modules/ZuckerReports/jasper/saaj-api-1.3.jar;modules/ZuckerReports/jasper/slf4j-api.jar;modules/ZuckerReports/jasper/slf4j-log4j12.jar;modules/ZuckerReports/jasper/spring.jar;modules/ZuckerReports/jasper/sqleonardo-2007.03.jar;modules/ZuckerReports/jasper/swingx-2007_10_07.jar;modules/ZuckerReports/jasper/xml-apis-ext.jar;modules/ZuckerReports/jasper/xml-apis.jar;modules/ZuckerReports/jasper/zuckerreports-1.0.jar" at.go_mobile.zuckerreports.JasperBatchMain custom/ZuckerReports/temp/aff882c1-684b-d2de-403e-4be367bc2f5f/cmd.properties 2&1 JasperBatchMain :: loading jasper design custom/ZuckerReports/resources/contact_counts_by_first_name.jasper JasperBatchMain :: getParameterValue(REPORT_PARAMETERS_MAP, java.util.Map) = null JasperBatchMain :: getParameterValue(JASPER_REPORT, net.sf.jasperreports.engine.JasperReport) = null JasperBatchMain :: getParameterValue(REPORT_CONNECTION, java.sql.Connection) = null JasperBatchMain :: getParameterValue(REPORT_MAX_COUNT, java.lang.Integer) = null JasperBatchMain :: getParameterValue(REPORT_DATA_SOURCE, net.sf.jasperreports.engine.JRDataSource) = null JasperBatchMain :: getParameterValue(REPORT_SCRIPTLET, net.sf.jasperreports.engine.JRAbstractScriptlet) = null JasperBatchMain :: getParameterValue(REPORT_LOCALE, java.util.Locale) = null JasperBatchMain :: getParameterValue(REPORT_RESOURCE_BUNDLE, java.util.ResourceBundle) = null JasperBatchMain :: getParameterValue(REPORT_TIME_ZONE, java.util.TimeZone) = null JasperBatchMain :: getParameterValue(REPORT_FORMAT_FACTORY, net.sf.jasperreports.engine.util.FormatFactory) = null JasperBatchMain :: getParameterValue(REPORT_CLASS_LOADER, java.lang.ClassLoader) = null JasperBatchMain :: getParameterValue(REPORT_URL_HANDLER_FACTORY, java.net.URLStreamHandlerFactory) = null JasperBatchMain :: getParameterValue(REPORT_FILE_RESOLVER, net.sf.jasperreports.engine.util.FileResolver) = null JasperBatchMain :: getParameterValue(REPORT_VIRTUALIZER, net.sf.jasperreports.engine.JRVirtualizer) = null JasperBatchMain :: getParameterValue(IS_IGNORE_PAGINATION, java.lang.Boolean) = null JasperBatchMain :: getParameterValue(REPORT_TEMPLATES, java.util.Collection) = null log4j:WARN No appenders could be found for logger (net.sf.jasperreports.extensions.ExtensionsEnviron ment). log4j:WARN Please initialize the log4j system properly. Exception in thread "main" java.lang.IllegalArgumentException: Null 'key' argument. at org.jfree.data.DefaultKeyedValues.setValue(Default KeyedValues.java:229) at org.jfree.data.DefaultKeyedValues2D.setValue(Defau ltKeyedValues2D.java:337) at org.jfree.data.DefaultKeyedValues2D.addValue(Defau ltKeyedValues2D.java:303) at org.jfree.data.category.DefaultCategoryDataset.add Value(DefaultCategoryDataset.java:222) at net.sf.jasperreports.charts.fill.JRFillCategoryDat aset.customIncrement(JRFillCategoryDataset.java:14 3) at net.sf.jasperreports.engine.fill.JRFillElementData set.increment(JRFillElementDataset.java:175) at net.sf.jasperreports.engine.fill.JRCalculator.calc ulateVariables(JRCalculator.java:148) at net.sf.jasperreports.engine.fill.JRVerticalFiller. fillDetail(JRVerticalFiller.java:736) at net.sf.jasperreports.engine.fill.JRVerticalFiller. fillReportContent(JRVerticalFiller.java:272) at net.sf.jasperreports.engine.fill.JRVerticalFiller. fillReport(JRVerticalFiller.java:114) at net.sf.jasperreports.engine.fill.JRBaseFiller.fill (JRBaseFiller.java:923) at net.sf.jasperreports.engine.fill.JRBaseFiller.fill (JRBaseFiller.java:826) at net.sf.jasperreports.engine.fill.JRFiller.fillRepo rt(JRFiller.java:59) at at.go_mobile.zuckerreports.JasperBatchMain.main(Ja sperBatchMain.java:126) The same report runs correctly in another SugarCRM installation on the same server. The installation in which the report runs correctly is of the same version, and has the same version of the ZuckerReports module. The report previously ran correctly on both installations. I think that the only changes that have been made on the installation in which the report now does not work since the report was last successfully run are the additions of a few custom fields in the Contacts module. These changes should have nothing to do with ZuckerReports. I have tried uninstalling and reinstalling the ZuckerReports module, but the problem remains. A google search for the warnings given in the error message ie. * log4j:WARN No appenders could be found for logger (net.sf.jasperreports.extensions.ExtensionsEnviron ment). * log4j:WARN Please initialize the log4j system properly. Returns a few links (not specific to ZuckerReports) with tips similar to the following: * log4j.properties or log4j.xml needs to be on the classpath where log4j can find it. I cannot find a file with either of those names anywhere on my server, and yet the report can be run successfully on one of my SugarCRM installations. So I figure log4j must be being configured another way. Can anyone suggest a way to solve this problem? Or explain how I might discover how log4j is configured in ZuckerReports? Or explain how I might compare the working with the non-working installation in order to help find a solution? (I have tried searching for files containing "log4j" in both installations and comparing but all I can find are .jar files (nothing I can read with a text editor), and the .jar files found in each installation appear to be the same.)

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  • Can't connect to samba

    - by Rick
    Windows 7, connecting to Samba shares I have a follow up question from the link above. I am running Samba 3.0.23d on FreeBSD is release 7.1 I changed the policies as described above but still cannot connect to the samba server with the windows 7 or a server 2008. I feel it is a problem with recognizing the new machines on the network. the windows machines can see the samba server, but cannot connect to it or view any of the files. After changing the security policies the samba server asked for network id and password but would not allow the machine to connect, said they were unknown username or bad password. Here is my current config file. there is no sign of encryption anywhere, should I just add the line? not sure what that would do elsewhere. Workgroup = WWOFFSET server string = WWO File Server (%v) security = server username map = /usr/local/etc/smb.users hosts allow = 10. 127. # If you want to automatically load your printer list rather # than setting them up individually then you'll need this ; load printers = yes # you may wish to override the location of the printcap file ; printcap name = /etc/printcap # on SystemV system setting printcap name to lpstat should allow # you to automatically obtain a printer list from the SystemV spool # system ; printcap name = lpstat # It should not be necessary to specify the print system type unless # it is non-standard. Currently supported print systems include: # bsd, cups, sysv, plp, lprng, aix, hpux, qnx ; printing = cups # Uncomment this if you want a guest account, you must add this to /etc/passwd # otherwise the user "nobody" is used ; guest account = pcguest # this tells Samba to use a separate log file for each machine # that connects log file = /var/log/samba/log.%m # Put a capping on the size of the log files (in Kb). max log size = 50 # Use password server option only with security = server # The argument list may include: # password server = My_PDC_Name [My_BDC_Name] [My_Next_BDC_Name] # or to auto-locate the domain controller/s # password server = * ; password server = <NT-Server-Name> password server = SERVER0 # Use the realm option only with security = ads # Specifies the Active Directory realm the host is part of ; realm = MY_REALM # Backend to store user information in. New installations should # use either tdbsam or ldapsam. smbpasswd is available for backwards # compatibility. tdbsam requires no further configuration. ; passdb backend = tdbsam ; passdb backend = smbpasswd # Using the following line enables you to customise your configuration # on a per machine basis. The %m gets replaced with the netbios name # of the machine that is connecting. # Note: Consider carefully the location in the configuration file of # this line. The included file is read at that point. ; include = /usr/local/etc/smb.conf.%m # Most people will find that this option gives better performance. # See the chapter 'Samba performance issues' in the Samba HOWTO Collection # and the manual pages for details. # You may want to add the following on a Linux system: # SO_RCVBUF=8192 SO_SNDBUF=8192 socket options = TCP_NODELAY # Configure Samba to use multiple interfaces # If you have multiple network interfaces then you must list them # here. See the man page for details. ; interfaces = 192.168.12.2/24 192.168.13.2/24 # Browser Control Options: # set local master to no if you don't want Samba to become a master # browser on your network. Otherwise the normal election rules apply ; local master = no # OS Level determines the precedence of this server in master browser # elections. The default value should be reasonable ; os level = 33 # Domain Master specifies Samba to be the Domain Master Browser. This # allows Samba to collate browse lists between subnets. Don't use this # if you already have a Windows NT domain controller doing this job ; domain master = yes # Preferred Master causes Samba to force a local browser election on startup # and gives it a slightly higher chance of winning the election ; preferred master = yes # Enable this if you want Samba to be a domain logon server for # Windows95 workstations. ; domain logons = yes # if you enable domain logons then you may want a per-machine or # per user logon script # run a specific logon batch file per workstation (machine) ; logon script = %m.bat # run a specific logon batch file per username ; logon script = %U.bat # Where to store roving profiles (only for Win95 and WinNT) # %L substitutes for this servers netbios name, %U is username # You must uncomment the [Profiles] share below ; logon path = \\%L\Profiles\%U # Windows Internet Name Serving Support Section: # WINS Support - Tells the NMBD component of Samba to enable it's WINS Server ; wins support = yes # WINS Server - Tells the NMBD components of Samba to be a WINS Client # Note: Samba can be either a WINS Server, or a WINS Client, but NOT both ; wins server = w.x.y.z # WINS Proxy - Tells Samba to answer name resolution queries on # behalf of a non WINS capable client, for this to work there must be # at least one WINS Server on the network. The default is NO. ; wins proxy = yes # DNS Proxy - tells Samba whether or not to try to resolve NetBIOS names # via DNS nslookups. The default is NO. dns proxy = no # charset settings ; display charset = ASCII ; unix charset = ASCII ; dos charset = ASCII # These scripts are used on a domain controller or stand-alone # machine to add or delete corresponding unix accounts ; add user script = /usr/sbin/useradd %u ; add group script = /usr/sbin/groupadd %g ; add machine script = /usr/sbin/adduser -n -g machines -c Machine -d /dev/null -s /bin/false %u ; delete user script = /usr/sbin/userdel %u ; delete user from group script = /usr/sbin/deluser %u %g ; delete group script = /usr/sbin/groupdel %g unix extensions = no

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  • Toorcon14

    - by danx
    Toorcon 2012 Information Security Conference San Diego, CA, http://www.toorcon.org/ Dan Anderson, October 2012 It's almost Halloween, and we all know what that means—yes, of course, it's time for another Toorcon Conference! Toorcon is an annual conference for people interested in computer security. This includes the whole range of hackers, computer hobbyists, professionals, security consultants, press, law enforcement, prosecutors, FBI, etc. We're at Toorcon 14—see earlier blogs for some of the previous Toorcon's I've attended (back to 2003). This year's "con" was held at the Westin on Broadway in downtown San Diego, California. The following are not necessarily my views—I'm just the messenger—although I could have misquoted or misparaphrased the speakers. Also, I only reviewed some of the talks, below, which I attended and interested me. MalAndroid—the Crux of Android Infections, Aditya K. Sood Programming Weird Machines with ELF Metadata, Rebecca "bx" Shapiro Privacy at the Handset: New FCC Rules?, Valkyrie Hacking Measured Boot and UEFI, Dan Griffin You Can't Buy Security: Building the Open Source InfoSec Program, Boris Sverdlik What Journalists Want: The Investigative Reporters' Perspective on Hacking, Dave Maas & Jason Leopold Accessibility and Security, Anna Shubina Stop Patching, for Stronger PCI Compliance, Adam Brand McAfee Secure & Trustmarks — a Hacker's Best Friend, Jay James & Shane MacDougall MalAndroid—the Crux of Android Infections Aditya K. Sood, IOActive, Michigan State PhD candidate Aditya talked about Android smartphone malware. There's a lot of old Android software out there—over 50% Gingerbread (2.3.x)—and most have unpatched vulnerabilities. Of 9 Android vulnerabilities, 8 have known exploits (such as the old Gingerbread Global Object Table exploit). Android protection includes sandboxing, security scanner, app permissions, and screened Android app market. The Android permission checker has fine-grain resource control, policy enforcement. Android static analysis also includes a static analysis app checker (bouncer), and a vulnerablity checker. What security problems does Android have? User-centric security, which depends on the user to grant permission and make smart decisions. But users don't care or think about malware (the're not aware, not paranoid). All they want is functionality, extensibility, mobility Android had no "proper" encryption before Android 3.0 No built-in protection against social engineering and web tricks Alternative Android app markets are unsafe. Simply visiting some markets can infect Android Aditya classified Android Malware types as: Type A—Apps. These interact with the Android app framework. For example, a fake Netflix app. Or Android Gold Dream (game), which uploads user files stealthy manner to a remote location. Type K—Kernel. Exploits underlying Linux libraries or kernel Type H—Hybrid. These use multiple layers (app framework, libraries, kernel). These are most commonly used by Android botnets, which are popular with Chinese botnet authors What are the threats from Android malware? These incude leak info (contacts), banking fraud, corporate network attacks, malware advertising, malware "Hackivism" (the promotion of social causes. For example, promiting specific leaders of the Tunisian or Iranian revolutions. Android malware is frequently "masquerated". That is, repackaged inside a legit app with malware. To avoid detection, the hidden malware is not unwrapped until runtime. The malware payload can be hidden in, for example, PNG files. Less common are Android bootkits—there's not many around. What they do is hijack the Android init framework—alteering system programs and daemons, then deletes itself. For example, the DKF Bootkit (China). Android App Problems: no code signing! all self-signed native code execution permission sandbox — all or none alternate market places no robust Android malware detection at network level delayed patch process Programming Weird Machines with ELF Metadata Rebecca "bx" Shapiro, Dartmouth College, NH https://github.com/bx/elf-bf-tools @bxsays on twitter Definitions. "ELF" is an executable file format used in linking and loading executables (on UNIX/Linux-class machines). "Weird machine" uses undocumented computation sources (I think of them as unintended virtual machines). Some examples of "weird machines" are those that: return to weird location, does SQL injection, corrupts the heap. Bx then talked about using ELF metadata as (an uintended) "weird machine". Some ELF background: A compiler takes source code and generates a ELF object file (hello.o). A static linker makes an ELF executable from the object file. A runtime linker and loader takes ELF executable and loads and relocates it in memory. The ELF file has symbols to relocate functions and variables. ELF has two relocation tables—one at link time and another one at loading time: .rela.dyn (link time) and .dynsym (dynamic table). GOT: Global Offset Table of addresses for dynamically-linked functions. PLT: Procedure Linkage Tables—works with GOT. The memory layout of a process (not the ELF file) is, in order: program (+ heap), dynamic libraries, libc, ld.so, stack (which includes the dynamic table loaded into memory) For ELF, the "weird machine" is found and exploited in the loader. ELF can be crafted for executing viruses, by tricking runtime into executing interpreted "code" in the ELF symbol table. One can inject parasitic "code" without modifying the actual ELF code portions. Think of the ELF symbol table as an "assembly language" interpreter. It has these elements: instructions: Add, move, jump if not 0 (jnz) Think of symbol table entries as "registers" symbol table value is "contents" immediate values are constants direct values are addresses (e.g., 0xdeadbeef) move instruction: is a relocation table entry add instruction: relocation table "addend" entry jnz instruction: takes multiple relocation table entries The ELF weird machine exploits the loader by relocating relocation table entries. The loader will go on forever until told to stop. It stores state on stack at "end" and uses IFUNC table entries (containing function pointer address). The ELF weird machine, called "Brainfu*k" (BF) has: 8 instructions: pointer inc, dec, inc indirect, dec indirect, jump forward, jump backward, print. Three registers - 3 registers Bx showed example BF source code that implemented a Turing machine printing "hello, world". More interesting was the next demo, where bx modified ping. Ping runs suid as root, but quickly drops privilege. BF modified the loader to disable the library function call dropping privilege, so it remained as root. Then BF modified the ping -t argument to execute the -t filename as root. It's best to show what this modified ping does with an example: $ whoami bx $ ping localhost -t backdoor.sh # executes backdoor $ whoami root $ The modified code increased from 285948 bytes to 290209 bytes. A BF tool compiles "executable" by modifying the symbol table in an existing ELF executable. The tool modifies .dynsym and .rela.dyn table, but not code or data. Privacy at the Handset: New FCC Rules? "Valkyrie" (Christie Dudley, Santa Clara Law JD candidate) Valkyrie talked about mobile handset privacy. Some background: Senator Franken (also a comedian) became alarmed about CarrierIQ, where the carriers track their customers. Franken asked the FCC to find out what obligations carriers think they have to protect privacy. The carriers' response was that they are doing just fine with self-regulation—no worries! Carriers need to collect data, such as missed calls, to maintain network quality. But carriers also sell data for marketing. Verizon sells customer data and enables this with a narrow privacy policy (only 1 month to opt out, with difficulties). The data sold is not individually identifiable and is aggregated. But Verizon recommends, as an aggregation workaround to "recollate" data to other databases to identify customers indirectly. The FCC has regulated telephone privacy since 1934 and mobile network privacy since 2007. Also, the carriers say mobile phone privacy is a FTC responsibility (not FCC). FTC is trying to improve mobile app privacy, but FTC has no authority over carrier / customer relationships. As a side note, Apple iPhones are unique as carriers have extra control over iPhones they don't have with other smartphones. As a result iPhones may be more regulated. Who are the consumer advocates? Everyone knows EFF, but EPIC (Electrnic Privacy Info Center), although more obsecure, is more relevant. What to do? Carriers must be accountable. Opt-in and opt-out at any time. Carriers need incentive to grant users control for those who want it, by holding them liable and responsible for breeches on their clock. Location information should be added current CPNI privacy protection, and require "Pen/trap" judicial order to obtain (and would still be a lower standard than 4th Amendment). Politics are on a pro-privacy swing now, with many senators and the Whitehouse. There will probably be new regulation soon, and enforcement will be a problem, but consumers will still have some benefit. Hacking Measured Boot and UEFI Dan Griffin, JWSecure, Inc., Seattle, @JWSdan Dan talked about hacking measured UEFI boot. First some terms: UEFI is a boot technology that is replacing BIOS (has whitelisting and blacklisting). UEFI protects devices against rootkits. TPM - hardware security device to store hashs and hardware-protected keys "secure boot" can control at firmware level what boot images can boot "measured boot" OS feature that tracks hashes (from BIOS, boot loader, krnel, early drivers). "remote attestation" allows remote validation and control based on policy on a remote attestation server. Microsoft pushing TPM (Windows 8 required), but Google is not. Intel TianoCore is the only open source for UEFI. Dan has Measured Boot Tool at http://mbt.codeplex.com/ with a demo where you can also view TPM data. TPM support already on enterprise-class machines. UEFI Weaknesses. UEFI toolkits are evolving rapidly, but UEFI has weaknesses: assume user is an ally trust TPM implicitly, and attached to computer hibernate file is unprotected (disk encryption protects against this) protection migrating from hardware to firmware delays in patching and whitelist updates will UEFI really be adopted by the mainstream (smartphone hardware support, bank support, apathetic consumer support) You Can't Buy Security: Building the Open Source InfoSec Program Boris Sverdlik, ISDPodcast.com co-host Boris talked about problems typical with current security audits. "IT Security" is an oxymoron—IT exists to enable buiness, uptime, utilization, reporting, but don't care about security—IT has conflict of interest. There's no Magic Bullet ("blinky box"), no one-size-fits-all solution (e.g., Intrusion Detection Systems (IDSs)). Regulations don't make you secure. The cloud is not secure (because of shared data and admin access). Defense and pen testing is not sexy. Auditors are not solution (security not a checklist)—what's needed is experience and adaptability—need soft skills. Step 1: First thing is to Google and learn the company end-to-end before you start. Get to know the management team (not IT team), meet as many people as you can. Don't use arbitrary values such as CISSP scores. Quantitive risk assessment is a myth (e.g. AV*EF-SLE). Learn different Business Units, legal/regulatory obligations, learn the business and where the money is made, verify company is protected from script kiddies (easy), learn sensitive information (IP, internal use only), and start with low-hanging fruit (customer service reps and social engineering). Step 2: Policies. Keep policies short and relevant. Generic SANS "security" boilerplate policies don't make sense and are not followed. Focus on acceptable use, data usage, communications, physical security. Step 3: Implementation: keep it simple stupid. Open source, although useful, is not free (implementation cost). Access controls with authentication & authorization for local and remote access. MS Windows has it, otherwise use OpenLDAP, OpenIAM, etc. Application security Everyone tries to reinvent the wheel—use existing static analysis tools. Review high-risk apps and major revisions. Don't run different risk level apps on same system. Assume host/client compromised and use app-level security control. Network security VLAN != segregated because there's too many workarounds. Use explicit firwall rules, active and passive network monitoring (snort is free), disallow end user access to production environment, have a proxy instead of direct Internet access. Also, SSL certificates are not good two-factor auth and SSL does not mean "safe." Operational Controls Have change, patch, asset, & vulnerability management (OSSI is free). For change management, always review code before pushing to production For logging, have centralized security logging for business-critical systems, separate security logging from administrative/IT logging, and lock down log (as it has everything). Monitor with OSSIM (open source). Use intrusion detection, but not just to fulfill a checkbox: build rules from a whitelist perspective (snort). OSSEC has 95% of what you need. Vulnerability management is a QA function when done right: OpenVas and Seccubus are free. Security awareness The reality is users will always click everything. Build real awareness, not compliance driven checkbox, and have it integrated into the culture. Pen test by crowd sourcing—test with logging COSSP http://www.cossp.org/ - Comprehensive Open Source Security Project What Journalists Want: The Investigative Reporters' Perspective on Hacking Dave Maas, San Diego CityBeat Jason Leopold, Truthout.org The difference between hackers and investigative journalists: For hackers, the motivation varies, but method is same, technological specialties. For investigative journalists, it's about one thing—The Story, and they need broad info-gathering skills. J-School in 60 Seconds: Generic formula: Person or issue of pubic interest, new info, or angle. Generic criteria: proximity, prominence, timeliness, human interest, oddity, or consequence. Media awareness of hackers and trends: journalists becoming extremely aware of hackers with congressional debates (privacy, data breaches), demand for data-mining Journalists, use of coding and web development for Journalists, and Journalists busted for hacking (Murdock). Info gathering by investigative journalists include Public records laws. Federal Freedom of Information Act (FOIA) is good, but slow. California Public Records Act is a lot stronger. FOIA takes forever because of foot-dragging—it helps to be specific. Often need to sue (especially FBI). CPRA is faster, and requests can be vague. Dumps and leaks (a la Wikileaks) Journalists want: leads, protecting ourselves, our sources, and adapting tools for news gathering (Google hacking). Anonomity is important to whistleblowers. They want no digital footprint left behind (e.g., email, web log). They don't trust encryption, want to feel safe and secure. Whistleblower laws are very weak—there's no upside for whistleblowers—they have to be very passionate to do it. Accessibility and Security or: How I Learned to Stop Worrying and Love the Halting Problem Anna Shubina, Dartmouth College Anna talked about how accessibility and security are related. Accessibility of digital content (not real world accessibility). mostly refers to blind users and screenreaders, for our purpose. Accessibility is about parsing documents, as are many security issues. "Rich" executable content causes accessibility to fail, and often causes security to fail. For example MS Word has executable format—it's not a document exchange format—more dangerous than PDF or HTML. Accessibility is often the first and maybe only sanity check with parsing. They have no choice because someone may want to read what you write. Google, for example, is very particular about web browser you use and are bad at supporting other browsers. Uses JavaScript instead of links, often requiring mouseover to display content. PDF is a security nightmare. Executible format, embedded flash, JavaScript, etc. 15 million lines of code. Google Chrome doesn't handle PDF correctly, causing several security bugs. PDF has an accessibility checker and PDF tagging, to help with accessibility. But no PDF checker checks for incorrect tags, untagged content, or validates lists or tables. None check executable content at all. The "Halting Problem" is: can one decide whether a program will ever stop? The answer, in general, is no (Rice's theorem). The same holds true for accessibility checkers. Language-theoretic Security says complicated data formats are hard to parse and cannot be solved due to the Halting Problem. W3C Web Accessibility Guidelines: "Perceivable, Operable, Understandable, Robust" Not much help though, except for "Robust", but here's some gems: * all information should be parsable (paraphrasing) * if not parsable, cannot be converted to alternate formats * maximize compatibility in new document formats Executible webpages are bad for security and accessibility. They say it's for a better web experience. But is it necessary to stuff web pages with JavaScript for a better experience? A good example is The Drudge Report—it has hand-written HTML with no JavaScript, yet drives a lot of web traffic due to good content. A bad example is Google News—hidden scrollbars, guessing user input. Solutions: Accessibility and security problems come from same source Expose "better user experience" myth Keep your corner of Internet parsable Remember "Halting Problem"—recognize false solutions (checking and verifying tools) Stop Patching, for Stronger PCI Compliance Adam Brand, protiviti @adamrbrand, http://www.picfun.com/ Adam talked about PCI compliance for retail sales. Take an example: for PCI compliance, 50% of Brian's time (a IT guy), 960 hours/year was spent patching POSs in 850 restaurants. Often applying some patches make no sense (like fixing a browser vulnerability on a server). "Scanner worship" is overuse of vulnerability scanners—it gives a warm and fuzzy and it's simple (red or green results—fix reds). Scanners give a false sense of security. In reality, breeches from missing patches are uncommon—more common problems are: default passwords, cleartext authentication, misconfiguration (firewall ports open). Patching Myths: Myth 1: install within 30 days of patch release (but PCI §6.1 allows a "risk-based approach" instead). Myth 2: vendor decides what's critical (also PCI §6.1). But §6.2 requires user ranking of vulnerabilities instead. Myth 3: scan and rescan until it passes. But PCI §11.2.1b says this applies only to high-risk vulnerabilities. Adam says good recommendations come from NIST 800-40. Instead use sane patching and focus on what's really important. From NIST 800-40: Proactive: Use a proactive vulnerability management process: use change control, configuration management, monitor file integrity. Monitor: start with NVD and other vulnerability alerts, not scanner results. Evaluate: public-facing system? workstation? internal server? (risk rank) Decide:on action and timeline Test: pre-test patches (stability, functionality, rollback) for change control Install: notify, change control, tickets McAfee Secure & Trustmarks — a Hacker's Best Friend Jay James, Shane MacDougall, Tactical Intelligence Inc., Canada "McAfee Secure Trustmark" is a website seal marketed by McAfee. A website gets this badge if they pass their remote scanning. The problem is a removal of trustmarks act as flags that you're vulnerable. Easy to view status change by viewing McAfee list on website or on Google. "Secure TrustGuard" is similar to McAfee. Jay and Shane wrote Perl scripts to gather sites from McAfee and search engines. If their certification image changes to a 1x1 pixel image, then they are longer certified. Their scripts take deltas of scans to see what changed daily. The bottom line is change in TrustGuard status is a flag for hackers to attack your site. Entire idea of seals is silly—you're raising a flag saying if you're vulnerable.

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  • Node.js Adventure - Host Node.js on Windows Azure Worker Role

    - by Shaun
    In my previous post I demonstrated about how to develop and deploy a Node.js application on Windows Azure Web Site (a.k.a. WAWS). WAWS is a new feature in Windows Azure platform. Since it’s low-cost, and it provides IIS and IISNode components so that we can host our Node.js application though Git, FTP and WebMatrix without any configuration and component installation. But sometimes we need to use the Windows Azure Cloud Service (a.k.a. WACS) and host our Node.js on worker role. Below are some benefits of using worker role. - WAWS leverages IIS and IISNode to host Node.js application, which runs in x86 WOW mode. It reduces the performance comparing with x64 in some cases. - WACS worker role does not need IIS, hence there’s no restriction of IIS, such as 8000 concurrent requests limitation. - WACS provides more flexibility and controls to the developers. For example, we can RDP to the virtual machines of our worker role instances. - WACS provides the service configuration features which can be changed when the role is running. - WACS provides more scaling capability than WAWS. In WAWS we can have at most 3 reserved instances per web site while in WACS we can have up to 20 instances in a subscription. - Since when using WACS worker role we starts the node by ourselves in a process, we can control the input, output and error stream. We can also control the version of Node.js.   Run Node.js in Worker Role Node.js can be started by just having its execution file. This means in Windows Azure, we can have a worker role with the “node.exe” and the Node.js source files, then start it in Run method of the worker role entry class. Let’s create a new windows azure project in Visual Studio and add a new worker role. Since we need our worker role execute the “node.exe” with our application code we need to add the “node.exe” into our project. Right click on the worker role project and add an existing item. By default the Node.js will be installed in the “Program Files\nodejs” folder so we can navigate there and add the “node.exe”. Then we need to create the entry code of Node.js. In WAWS the entry file must be named “server.js”, which is because it’s hosted by IIS and IISNode and IISNode only accept “server.js”. But here as we control everything we can choose any files as the entry code. For example, I created a new JavaScript file named “index.js” in project root. Since we created a C# Windows Azure project we cannot create a JavaScript file from the context menu “Add new item”. We have to create a text file, and then rename it to JavaScript extension. After we added these two files we should set their “Copy to Output Directory” property to “Copy Always”, or “Copy if Newer”. Otherwise they will not be involved in the package when deployed. Let’s paste a very simple Node.js code in the “index.js” as below. As you can see I created a web server listening at port 12345. 1: var http = require("http"); 2: var port = 12345; 3:  4: http.createServer(function (req, res) { 5: res.writeHead(200, { "Content-Type": "text/plain" }); 6: res.end("Hello World\n"); 7: }).listen(port); 8:  9: console.log("Server running at port %d", port); Then we need to start “node.exe” with this file when our worker role was started. This can be done in its Run method. I found the Node.js and entry JavaScript file name, and then create a new process to run it. Our worker role will wait for the process to be exited. If everything is OK once our web server was opened the process will be there listening for incoming requests, and should not be terminated. The code in worker role would be like this. 1: public override void Run() 2: { 3: // This is a sample worker implementation. Replace with your logic. 4: Trace.WriteLine("NodejsHost entry point called", "Information"); 5:  6: // retrieve the node.exe and entry node.js source code file name. 7: var node = Environment.ExpandEnvironmentVariables(@"%RoleRoot%\approot\node.exe"); 8: var js = "index.js"; 9:  10: // prepare the process starting of node.exe 11: var info = new ProcessStartInfo(node, js) 12: { 13: CreateNoWindow = false, 14: ErrorDialog = true, 15: WindowStyle = ProcessWindowStyle.Normal, 16: UseShellExecute = false, 17: WorkingDirectory = Environment.ExpandEnvironmentVariables(@"%RoleRoot%\approot") 18: }; 19: Trace.WriteLine(string.Format("{0} {1}", node, js), "Information"); 20:  21: // start the node.exe with entry code and wait for exit 22: var process = Process.Start(info); 23: process.WaitForExit(); 24: } Then we can run it locally. In the computer emulator UI the worker role started and it executed the Node.js, then Node.js windows appeared. Open the browser to verify the website hosted by our worker role. Next let’s deploy it to azure. But we need some additional steps. First, we need to create an input endpoint. By default there’s no endpoint defined in a worker role. So we will open the role property window in Visual Studio, create a new input TCP endpoint to the port we want our website to use. In this case I will use 80. Even though we created a web server we should add a TCP endpoint of the worker role, since Node.js always listen on TCP instead of HTTP. And then changed the “index.js”, let our web server listen on 80. 1: var http = require("http"); 2: var port = 80; 3:  4: http.createServer(function (req, res) { 5: res.writeHead(200, { "Content-Type": "text/plain" }); 6: res.end("Hello World\n"); 7: }).listen(port); 8:  9: console.log("Server running at port %d", port); Then publish it to Windows Azure. And then in browser we can see our Node.js website was running on WACS worker role. We may encounter an error if we tried to run our Node.js website on 80 port at local emulator. This is because the compute emulator registered 80 and map the 80 endpoint to 81. But our Node.js cannot detect this operation. So when it tried to listen on 80 it will failed since 80 have been used.   Use NPM Modules When we are using WAWS to host Node.js, we can simply install modules we need, and then just publish or upload all files to WAWS. But if we are using WACS worker role, we have to do some extra steps to make the modules work. Assuming that we plan to use “express” in our application. Firstly of all we should download and install this module through NPM command. But after the install finished, they are just in the disk but not included in the worker role project. If we deploy the worker role right now the module will not be packaged and uploaded to azure. Hence we need to add them to the project. On solution explorer window click the “Show all files” button, select the “node_modules” folder and in the context menu select “Include In Project”. But that not enough. We also need to make all files in this module to “Copy always” or “Copy if newer”, so that they can be uploaded to azure with the “node.exe” and “index.js”. This is painful step since there might be many files in a module. So I created a small tool which can update a C# project file, make its all items as “Copy always”. The code is very simple. 1: static void Main(string[] args) 2: { 3: if (args.Length < 1) 4: { 5: Console.WriteLine("Usage: copyallalways [project file]"); 6: return; 7: } 8:  9: var proj = args[0]; 10: File.Copy(proj, string.Format("{0}.bak", proj)); 11:  12: var xml = new XmlDocument(); 13: xml.Load(proj); 14: var nsManager = new XmlNamespaceManager(xml.NameTable); 15: nsManager.AddNamespace("pf", "http://schemas.microsoft.com/developer/msbuild/2003"); 16:  17: // add the output setting to copy always 18: var contentNodes = xml.SelectNodes("//pf:Project/pf:ItemGroup/pf:Content", nsManager); 19: UpdateNodes(contentNodes, xml, nsManager); 20: var noneNodes = xml.SelectNodes("//pf:Project/pf:ItemGroup/pf:None", nsManager); 21: UpdateNodes(noneNodes, xml, nsManager); 22: xml.Save(proj); 23:  24: // remove the namespace attributes 25: var content = xml.InnerXml.Replace("<CopyToOutputDirectory xmlns=\"\">", "<CopyToOutputDirectory>"); 26: xml.LoadXml(content); 27: xml.Save(proj); 28: } 29:  30: static void UpdateNodes(XmlNodeList nodes, XmlDocument xml, XmlNamespaceManager nsManager) 31: { 32: foreach (XmlNode node in nodes) 33: { 34: var copyToOutputDirectoryNode = node.SelectSingleNode("pf:CopyToOutputDirectory", nsManager); 35: if (copyToOutputDirectoryNode == null) 36: { 37: var n = xml.CreateNode(XmlNodeType.Element, "CopyToOutputDirectory", null); 38: n.InnerText = "Always"; 39: node.AppendChild(n); 40: } 41: else 42: { 43: if (string.Compare(copyToOutputDirectoryNode.InnerText, "Always", true) != 0) 44: { 45: copyToOutputDirectoryNode.InnerText = "Always"; 46: } 47: } 48: } 49: } Please be careful when use this tool. I created only for demo so do not use it directly in a production environment. Unload the worker role project, execute this tool with the worker role project file name as the command line argument, it will set all items as “Copy always”. Then reload this worker role project. Now let’s change the “index.js” to use express. 1: var express = require("express"); 2: var app = express(); 3:  4: var port = 80; 5:  6: app.configure(function () { 7: }); 8:  9: app.get("/", function (req, res) { 10: res.send("Hello Node.js!"); 11: }); 12:  13: app.get("/User/:id", function (req, res) { 14: var id = req.params.id; 15: res.json({ 16: "id": id, 17: "name": "user " + id, 18: "company": "IGT" 19: }); 20: }); 21:  22: app.listen(port); Finally let’s publish it and have a look in browser.   Use Windows Azure SQL Database We can use Windows Azure SQL Database (a.k.a. WACD) from Node.js as well on worker role hosting. Since we can control the version of Node.js, here we can use x64 version of “node-sqlserver” now. This is better than if we host Node.js on WAWS since it only support x86. Just install the “node-sqlserver” module from NPM, copy the “sqlserver.node” from “Build\Release” folder to “Lib” folder. Include them in worker role project and run my tool to make them to “Copy always”. Finally update the “index.js” to use WASD. 1: var express = require("express"); 2: var sql = require("node-sqlserver"); 3:  4: var connectionString = "Driver={SQL Server Native Client 10.0};Server=tcp:{SERVER NAME}.database.windows.net,1433;Database={DATABASE NAME};Uid={LOGIN}@{SERVER NAME};Pwd={PASSWORD};Encrypt=yes;Connection Timeout=30;"; 5: var port = 80; 6:  7: var app = express(); 8:  9: app.configure(function () { 10: app.use(express.bodyParser()); 11: }); 12:  13: app.get("/", function (req, res) { 14: sql.open(connectionString, function (err, conn) { 15: if (err) { 16: console.log(err); 17: res.send(500, "Cannot open connection."); 18: } 19: else { 20: conn.queryRaw("SELECT * FROM [Resource]", function (err, results) { 21: if (err) { 22: console.log(err); 23: res.send(500, "Cannot retrieve records."); 24: } 25: else { 26: res.json(results); 27: } 28: }); 29: } 30: }); 31: }); 32:  33: app.get("/text/:key/:culture", function (req, res) { 34: sql.open(connectionString, function (err, conn) { 35: if (err) { 36: console.log(err); 37: res.send(500, "Cannot open connection."); 38: } 39: else { 40: var key = req.params.key; 41: var culture = req.params.culture; 42: var command = "SELECT * FROM [Resource] WHERE [Key] = '" + key + "' AND [Culture] = '" + culture + "'"; 43: conn.queryRaw(command, function (err, results) { 44: if (err) { 45: console.log(err); 46: res.send(500, "Cannot retrieve records."); 47: } 48: else { 49: res.json(results); 50: } 51: }); 52: } 53: }); 54: }); 55:  56: app.get("/sproc/:key/:culture", function (req, res) { 57: sql.open(connectionString, function (err, conn) { 58: if (err) { 59: console.log(err); 60: res.send(500, "Cannot open connection."); 61: } 62: else { 63: var key = req.params.key; 64: var culture = req.params.culture; 65: var command = "EXEC GetItem '" + key + "', '" + culture + "'"; 66: conn.queryRaw(command, function (err, results) { 67: if (err) { 68: console.log(err); 69: res.send(500, "Cannot retrieve records."); 70: } 71: else { 72: res.json(results); 73: } 74: }); 75: } 76: }); 77: }); 78:  79: app.post("/new", function (req, res) { 80: var key = req.body.key; 81: var culture = req.body.culture; 82: var val = req.body.val; 83:  84: sql.open(connectionString, function (err, conn) { 85: if (err) { 86: console.log(err); 87: res.send(500, "Cannot open connection."); 88: } 89: else { 90: var command = "INSERT INTO [Resource] VALUES ('" + key + "', '" + culture + "', N'" + val + "')"; 91: conn.queryRaw(command, function (err, results) { 92: if (err) { 93: console.log(err); 94: res.send(500, "Cannot retrieve records."); 95: } 96: else { 97: res.send(200, "Inserted Successful"); 98: } 99: }); 100: } 101: }); 102: }); 103:  104: app.listen(port); Publish to azure and now we can see our Node.js is working with WASD through x64 version “node-sqlserver”.   Summary In this post I demonstrated how to host our Node.js in Windows Azure Cloud Service worker role. By using worker role we can control the version of Node.js, as well as the entry code. And it’s possible to do some pre jobs before the Node.js application started. It also removed the IIS and IISNode limitation. I personally recommended to use worker role as our Node.js hosting. But there are some problem if you use the approach I mentioned here. The first one is, we need to set all JavaScript files and module files as “Copy always” or “Copy if newer” manually. The second one is, in this way we cannot retrieve the cloud service configuration information. For example, we defined the endpoint in worker role property but we also specified the listening port in Node.js hardcoded. It should be changed that our Node.js can retrieve the endpoint. But I can tell you it won’t be working here. In the next post I will describe another way to execute the “node.exe” and Node.js application, so that we can get the cloud service configuration in Node.js. I will also demonstrate how to use Windows Azure Storage from Node.js by using the Windows Azure Node.js SDK.   Hope this helps, Shaun All documents and related graphics, codes are provided "AS IS" without warranty of any kind. Copyright © Shaun Ziyan Xu. This work is licensed under the Creative Commons License.

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  • The Incremental Architect&acute;s Napkin &ndash; #3 &ndash; Make Evolvability inevitable

    - by Ralf Westphal
    Originally posted on: http://geekswithblogs.net/theArchitectsNapkin/archive/2014/06/04/the-incremental-architectacutes-napkin-ndash-3-ndash-make-evolvability-inevitable.aspxThe easier something to measure the more likely it will be produced. Deviations between what is and what should be can be readily detected. That´s what automated acceptance tests are for. That´s what sprint reviews in Scrum are for. It´s no small wonder our software looks like it looks. It has all the traits whose conformance with requirements can easily be measured. And it´s lacking traits which cannot easily be measured. Evolvability (or Changeability) is such a trait. If an operation is correct, if an operation if fast enough, that can be checked very easily. But whether Evolvability is high or low, that cannot be checked by taking a measure or two. Evolvability might correlate with certain traits, e.g. number of lines of code (LOC) per function or Cyclomatic Complexity or test coverage. But there is no threshold value signalling “evolvability too low”; also Evolvability is hardly tangible for the customer. Nevertheless Evolvability is of great importance - at least in the long run. You can get away without much of it for a short time. Eventually, though, it´s needed like any other requirement. Or even more. Because without Evolvability no other requirement can be implemented. Evolvability is the foundation on which all else is build. Such fundamental importance is in stark contrast with its immeasurability. To compensate this, Evolvability must be put at the very center of software development. It must become the hub around everything else revolves. Since we cannot measure Evolvability, though, we cannot start watching it more. Instead we need to establish practices to keep it high (enough) at all times. Chefs have known that for long. That´s why everybody in a restaurant kitchen is constantly seeing after cleanliness. Hygiene is important as is to have clean tools at standardized locations. Only then the health of the patrons can be guaranteed and production efficiency is constantly high. Still a kitchen´s level of cleanliness is easier to measure than software Evolvability. That´s why important practices like reviews, pair programming, or TDD are not enough, I guess. What we need to keep Evolvability in focus and high is… to continually evolve. Change must not be something to avoid but too embrace. To me that means the whole change cycle from requirement analysis to delivery needs to be gone through more often. Scrum´s sprints of 4, 2 even 1 week are too long. Kanban´s flow of user stories across is too unreliable; it takes as long as it takes. Instead we should fix the cycle time at 2 days max. I call that Spinning. No increment must take longer than from this morning until tomorrow evening to finish. Then it should be acceptance checked by the customer (or his/her representative, e.g. a Product Owner). For me there are several resasons for such a fixed and short cycle time for each increment: Clear expectations Absolute estimates (“This will take X days to complete.”) are near impossible in software development as explained previously. Too much unplanned research and engineering work lurk in every feature. And then pervasive interruptions of work by peers and management. However, the smaller the scope the better our absolute estimates become. That´s because we understand better what really are the requirements and what the solution should look like. But maybe more importantly the shorter the timespan the more we can control how we use our time. So much can happen over the course of a week and longer timespans. But if push comes to shove I can block out all distractions and interruptions for a day or possibly two. That´s why I believe we can give rough absolute estimates on 3 levels: Noon Tonight Tomorrow Think of a meeting with a Product Owner at 8:30 in the morning. If she asks you, how long it will take you to implement a user story or bug fix, you can say, “It´ll be fixed by noon.”, or you can say, “I can manage to implement it until tonight before I leave.”, or you can say, “You´ll get it by tomorrow night at latest.” Yes, I believe all else would be naive. If you´re not confident to get something done by tomorrow night (some 34h from now) you just cannot reliably commit to any timeframe. That means you should not promise anything, you should not even start working on the issue. So when estimating use these four categories: Noon, Tonight, Tomorrow, NoClue - with NoClue meaning the requirement needs to be broken down further so each aspect can be assigned to one of the first three categories. If you like absolute estimates, here you go. But don´t do deep estimates. Don´t estimate dozens of issues; don´t think ahead (“Issue A is a Tonight, then B will be a Tomorrow, after that it´s C as a Noon, finally D is a Tonight - that´s what I´ll do this week.”). Just estimate so Work-in-Progress (WIP) is 1 for everybody - plus a small number of buffer issues. To be blunt: Yes, this makes promises impossible as to what a team will deliver in terms of scope at a certain date in the future. But it will give a Product Owner a clear picture of what to pull for acceptance feedback tonight and tomorrow. Trust through reliability Our trade is lacking trust. Customers don´t trust software companies/departments much. Managers don´t trust developers much. I find that perfectly understandable in the light of what we´re trying to accomplish: delivering software in the face of uncertainty by means of material good production. Customers as well as managers still expect software development to be close to production of houses or cars. But that´s a fundamental misunderstanding. Software development ist development. It´s basically research. As software developers we´re constantly executing experiments to find out what really provides value to users. We don´t know what they need, we just have mediated hypothesises. That´s why we cannot reliably deliver on preposterous demands. So trust is out of the window in no time. If we switch to delivering in short cycles, though, we can regain trust. Because estimates - explicit or implicit - up to 32 hours at most can be satisfied. I´d say: reliability over scope. It´s more important to reliably deliver what was promised then to cover a lot of requirement area. So when in doubt promise less - but deliver without delay. Deliver on scope (Functionality and Quality); but also deliver on Evolvability, i.e. on inner quality according to accepted principles. Always. Trust will be the reward. Less complexity of communication will follow. More goodwill buffer will follow. So don´t wait for some Kanban board to show you, that flow can be improved by scheduling smaller stories. You don´t need to learn that the hard way. Just start with small batch sizes of three different sizes. Fast feedback What has been finished can be checked for acceptance. Why wait for a sprint of several weeks to end? Why let the mental model of the issue and its solution dissipate? If you get final feedback after one or two weeks, you hardly remember what you did and why you did it. Resoning becomes hard. But more importantly youo probably are not in the mood anymore to go back to something you deemed done a long time ago. It´s boring, it´s frustrating to open up that mental box again. Learning is harder the longer it takes from event to feedback. Effort can be wasted between event (finishing an issue) and feedback, because other work might go in the wrong direction based on false premises. Checking finished issues for acceptance is the most important task of a Product Owner. It´s even more important than planning new issues. Because as long as work started is not released (accepted) it´s potential waste. So before starting new work better make sure work already done has value. By putting the emphasis on acceptance rather than planning true pull is established. As long as planning and starting work is more important, it´s a push process. Accept a Noon issue on the same day before leaving. Accept a Tonight issue before leaving today or first thing tomorrow morning. Accept a Tomorrow issue tomorrow night before leaving or early the day after tomorrow. After acceptance the developer(s) can start working on the next issue. Flexibility As if reliability/trust and fast feedback for less waste weren´t enough economic incentive, there is flexibility. After each issue the Product Owner can change course. If on Monday morning feature slices A, B, C, D, E were important and A, B, C were scheduled for acceptance by Monday evening and Tuesday evening, the Product Owner can change her mind at any time. Maybe after A got accepted she asks for continuation with D. But maybe, just maybe, she has gotten a completely different idea by then. Maybe she wants work to continue on F. And after B it´s neither D nor E, but G. And after G it´s D. With Spinning every 32 hours at latest priorities can be changed. And nothing is lost. Because what got accepted is of value. It provides an incremental value to the customer/user. Or it provides internal value to the Product Owner as increased knowledge/decreased uncertainty. I find such reactivity over commitment economically very benefical. Why commit a team to some workload for several weeks? It´s unnecessary at beast, and inflexible and wasteful at worst. If we cannot promise delivery of a certain scope on a certain date - which is what customers/management usually want -, we can at least provide them with unpredecented flexibility in the face of high uncertainty. Where the path is not clear, cannot be clear, make small steps so you´re able to change your course at any time. Premature completion Customers/management are used to premeditating budgets. They want to know exactly how much to pay for a certain amount of requirements. That´s understandable. But it does not match with the nature of software development. We should know that by now. Maybe there´s somewhere in the world some team who can consistently deliver on scope, quality, and time, and budget. Great! Congratulations! I, however, haven´t seen such a team yet. Which does not mean it´s impossible, but I think it´s nothing I can recommend to strive for. Rather I´d say: Don´t try this at home. It might hurt you one way or the other. However, what we can do, is allow customers/management stop work on features at any moment. With spinning every 32 hours a feature can be declared as finished - even though it might not be completed according to initial definition. I think, progress over completion is an important offer software development can make. Why think in terms of completion beyond a promise for the next 32 hours? Isn´t it more important to constantly move forward? Step by step. We´re not running sprints, we´re not running marathons, not even ultra-marathons. We´re in the sport of running forever. That makes it futile to stare at the finishing line. The very concept of a burn-down chart is misleading (in most cases). Whoever can only think in terms of completed requirements shuts out the chance for saving money. The requirements for a features mostly are uncertain. So how does a Product Owner know in the first place, how much is needed. Maybe more than specified is needed - which gets uncovered step by step with each finished increment. Maybe less than specified is needed. After each 4–32 hour increment the Product Owner can do an experient (or invite users to an experiment) if a particular trait of the software system is already good enough. And if so, she can switch the attention to a different aspect. In the end, requirements A, B, C then could be finished just 70%, 80%, and 50%. What the heck? It´s good enough - for now. 33% money saved. Wouldn´t that be splendid? Isn´t that a stunning argument for any budget-sensitive customer? You can save money and still get what you need? Pull on practices So far, in addition to more trust, more flexibility, less money spent, Spinning led to “doing less” which also means less code which of course means higher Evolvability per se. Last but not least, though, I think Spinning´s short acceptance cycles have one more effect. They excert pull-power on all sorts of practices known for increasing Evolvability. If, for example, you believe high automated test coverage helps Evolvability by lowering the fear of inadverted damage to a code base, why isn´t 90% of the developer community practicing automated tests consistently? I think, the answer is simple: Because they can do without. Somehow they manage to do enough manual checks before their rare releases/acceptance checks to ensure good enough correctness - at least in the short term. The same goes for other practices like component orientation, continuous build/integration, code reviews etc. None of that is compelling, urgent, imperative. Something else always seems more important. So Evolvability principles and practices fall through the cracks most of the time - until a project hits a wall. Then everybody becomes desperate; but by then (re)gaining Evolvability has become as very, very difficult and tedious undertaking. Sometimes up to the point where the existence of a project/company is in danger. With Spinning that´s different. If you´re practicing Spinning you cannot avoid all those practices. With Spinning you very quickly realize you cannot deliver reliably even on your 32 hour promises. Spinning thus is pulling on developers to adopt principles and practices for Evolvability. They will start actively looking for ways to keep their delivery rate high. And if not, management will soon tell them to do that. Because first the Product Owner then management will notice an increasing difficulty to deliver value within 32 hours. There, finally there emerges a way to measure Evolvability: The more frequent developers tell the Product Owner there is no way to deliver anything worth of feedback until tomorrow night, the poorer Evolvability is. Don´t count the “WTF!”, count the “No way!” utterances. In closing For sustainable software development we need to put Evolvability first. Functionality and Quality must not rule software development but be implemented within a framework ensuring (enough) Evolvability. Since Evolvability cannot be measured easily, I think we need to put software development “under pressure”. Software needs to be changed more often, in smaller increments. Each increment being relevant to the customer/user in some way. That does not mean each increment is worthy of shipment. It´s sufficient to gain further insight from it. Increments primarily serve the reduction of uncertainty, not sales. Sales even needs to be decoupled from this incremental progress. No more promises to sales. No more delivery au point. Rather sales should look at a stream of accepted increments (or incremental releases) and scoup from that whatever they find valuable. Sales and marketing need to realize they should work on what´s there, not what might be possible in the future. But I digress… In my view a Spinning cycle - which is not easy to reach, which requires practice - is the core practice to compensate the immeasurability of Evolvability. From start to finish of each issue in 32 hours max - that´s the challenge we need to accept if we´re serious increasing Evolvability. Fortunately higher Evolvability is not the only outcome of Spinning. Customer/management will like the increased flexibility and “getting more bang for the buck”.

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  • ANTS CLR and Memory Profiler In Depth Review (Part 1 of 2 &ndash; CLR Profiler)

    - by ToStringTheory
    One of the things that people might not know about me, is my obsession to make my code as efficient as possible.  Many people might not realize how much of a task or undertaking that this might be, but it is surely a task as monumental as climbing Mount Everest, except this time it is a challenge for the mind…  In trying to make code efficient, there are many different factors that play a part – size of project or solution, tiers, language used, experience and training of the programmer, technologies used, maintainability of the code – the list can go on for quite some time. I spend quite a bit of time when developing trying to determine what is the best way to implement a feature to accomplish the efficiency that I look to achieve.  One program that I have recently come to learn about – Red Gate ANTS Performance (CLR) and Memory profiler gives me tools to accomplish that job more efficiently as well.  In this review, I am going to cover some of the features of the ANTS profiler set by compiling some hideous example code to test against. Notice As a member of the Geeks With Blogs Influencers program, one of the perks is the ability to review products, in exchange for a free license to the program.  I have not let this affect my opinions of the product in any way, and Red Gate nor Geeks With Blogs has tried to influence my opinion regarding this product in any way. Introduction The ANTS Profiler pack provided by Red Gate was something that I had not heard of before receiving an email regarding an offer to review it for a license.  Since I look to make my code efficient, it was a no brainer for me to try it out!  One thing that I have to say took me by surprise is that upon downloading the program and installing it you fill out a form for your usual contact information.  Sure enough within 2 hours, I received an email from a sales representative at Red Gate asking if she could help me to achieve the most out of my trial time so it wouldn’t go to waste.  After replying to her and explaining that I was looking to review its feature set, she put me in contact with someone that setup a demo session to give me a quick rundown of its features via an online meeting.  After having dealt with a massive ordeal with one of my utility companies and their complete lack of customer service, Red Gates friendly and helpful representatives were a breath of fresh air, and something I was thankful for. ANTS CLR Profiler The ANTS CLR profiler is the thing I want to focus on the most in this post, so I am going to dive right in now. Install was simple and took no time at all.  It installed both the profiler for the CLR and Memory, but also visual studio extensions to facilitate the usage of the profilers (click any images for full size images): The Visual Studio menu options (under ANTS menu) Starting the CLR Performance Profiler from the start menu yields this window If you follow the instructions after launching the program from the start menu (Click File > New Profiling Session to start a new project), you are given a dialog with plenty of options for profiling: The New Session dialog.  Lots of options.  One thing I noticed is that the buttons in the lower right were half-covered by the panel of the application.  If I had to guess, I would imagine that this is caused by my DPI settings being set to 125%.  This is a problem I have seen in other applications as well that don’t scale well to different dpi scales. The profiler options give you the ability to profile: .NET Executable ASP.NET web application (hosted in IIS) ASP.NET web application (hosted in IIS express) ASP.NET web application (hosted in Cassini Web Development Server) SharePoint web application (hosted in IIS) Silverlight 4+ application Windows Service COM+ server XBAP (local XAML browser application) Attach to an already running .NET 4 process Choosing each option provides a varying set of other variables/options that one can set including options such as application arguments, operating path, record I/O performance performance counters to record (43 counters in all!), etc…  All in all, they give you the ability to profile many different .Net project types, and make it simple to do so.  In most cases of my using this application, I would be using the built in Visual Studio extensions, as they automatically start a new profiling project in ANTS with the options setup, and start your program, however RedGate has made it easy enough to profile outside of Visual Studio as well. On the flip side of this, as someone who lives most of their work life in Visual Studio, one thing I do wish is that instead of opening an entirely separate application/gui to perform profiling after launching, that instead they would provide a Visual Studio panel with the information, and integrate more of the profiling project information into Visual Studio.  So, now that we have an idea of what options that the profiler gives us, its time to test its abilities and features. Horrendous Example Code – Prime Number Generator One of my interests besides development, is Physics and Math – what I went to college for.  I have especially always been interested in prime numbers, as they are something of a mystery…  So, I decided that I would go ahead and to test the abilities of the profiler, I would write a small program, website, and library to generate prime numbers in the quantity that you ask for.  I am going to start off with some terrible code, and show how I would see the profiler being used as a development tool. First off, the IPrimes interface (all code is downloadable at the end of the post): interface IPrimes { IEnumerable<int> GetPrimes(int retrieve); } Simple enough, right?  Anything that implements the interface will (hopefully) provide an IEnumerable of int, with the quantity specified in the parameter argument.  Next, I am going to implement this interface in the most basic way: public class DumbPrimes : IPrimes { public IEnumerable<int> GetPrimes(int retrieve) { //store a list of primes already found var _foundPrimes = new List<int>() { 2, 3 }; //if i ask for 1 or two primes, return what asked for if (retrieve <= _foundPrimes.Count()) return _foundPrimes.Take(retrieve); //the next number to look at int _analyzing = 4; //since I already determined I don't have enough //execute at least once, and until quantity is sufficed do { //assume prime until otherwise determined bool isPrime = true; //start dividing at 2 //divide until number is reached, or determined not prime for (int i = 2; i < _analyzing && isPrime; i++) { //if (i) goes into _analyzing without a remainder, //_analyzing is NOT prime if (_analyzing % i == 0) isPrime = false; } //if it is prime, add to found list if (isPrime) _foundPrimes.Add(_analyzing); //increment number to analyze next _analyzing++; } while (_foundPrimes.Count() < retrieve); return _foundPrimes; } } This is the simplest way to get primes in my opinion.  Checking each number by the straight definition of a prime – is it divisible by anything besides 1 and itself. I have included this code in a base class library for my solution, as I am going to use it to demonstrate a couple of features of ANTS.  This class library is consumed by a simple non-MVVM WPF application, and a simple MVC4 website.  I will not post the WPF code here inline, as it is simply an ObservableCollection<int>, a label, two textbox’s, and a button. Starting a new Profiling Session So, in Visual Studio, I have just completed my first stint developing the GUI and DumbPrimes IPrimes class, so now I want to check my codes efficiency by profiling it.  All I have to do is build the solution (surprised initiating a profiling session doesn’t do this, but I suppose I can understand it), and then click the ANTS menu, followed by Profile Performance.  I am then greeted by the profiler starting up and already monitoring my program live: You are provided with a realtime graph at the top, and a pane at the bottom giving you information on how to proceed.  I am going to start by asking my program to show me the first 15000 primes: After the program finally began responding again (I did all the work on the main UI thread – how bad!), I stopped the profiler, which did kill the process of my program too.  One important thing to note, is that the profiler by default wants to give you a lot of detail about the operation – line hit counts, time per line, percent time per line, etc…  The important thing to remember is that this itself takes a lot of time.  When running my program without the profiler attached, it can generate the 15000 primes in 5.18 seconds, compared to 74.5 seconds – almost a 1500 percent increase.  While this may seem like a lot, remember that there is a trade off.  It may be WAY more inefficient, however, I am able to drill down and make improvements to specific problem areas, and then decrease execution time all around. Analyzing the Profiling Session After clicking ‘Stop Profiling’, the process running my application stopped, and the entire execution time was automatically selected by ANTS, and the results shown below: Now there are a number of interesting things going on here, I am going to cover each in a section of its own: Real Time Performance Counter Bar (top of screen) At the top of the screen, is the real time performance bar.  As your application is running, this will constantly update with the currently selected performance counters status.  A couple of cool things to note are the fact that you can drag a selection around specific time periods to drill down the detail views in the lower 2 panels to information pertaining to only that period. After selecting a time period, you can bookmark a section and name it, so that it is easy to find later, or after reloaded at a later time.  You can also zoom in, out, or fit the graph to the space provided – useful for drilling down. It may be hard to see, but at the top of the processor time graph below the time ticks, but above the red usage graph, there is a green bar. This bar shows at what times a method that is selected in the ‘Call tree’ panel is called. Very cool to be able to click on a method and see at what times it made an impact. As I said before, ANTS provides 43 different performance counters you can hook into.  Click the arrow next to the Performance tab at the top will allow you to change between different counters if you have them selected: Method Call Tree, ADO.Net Database Calls, File IO – Detail Panel Red Gate really hit the mark here I think. When you select a section of the run with the graph, the call tree populates to fill a hierarchical tree of method calls, with information regarding each of the methods.   By default, methods are hidden where the source is not provided (framework type code), however, Red Gate has integrated Reflector into ANTS, so even if you don’t have source for something, you can select a method and get the source if you want.  Methods are also hidden where the impact is seen as insignificant – methods that are only executed for 1% of the time of the overall calling methods time; in other words, working on making them better is not where your efforts should be focused. – Smart! Source Panel – Detail Panel The source panel is where you can see line level information on your code, showing the code for the currently selected method from the Method Call Tree.  If the code is not available, Reflector takes care of it and shows the code anyways! As you can notice, there does seem to be a problem with how ANTS determines what line is the actual line that a call is completed on.  I have suspicions that this may be due to some of the inline code optimizations that the CLR applies upon compilation of the assembly.  In a method with comments, the problem is much more severe: As you can see here, apparently the most offending code in my base library was a comment – *gasp*!  Removing the comments does help quite a bit, however I hope that Red Gate works on their counter algorithm soon to improve the logic on positioning for statistics: I did a small test just to demonstrate the lines are correct without comments. For me, it isn’t a deal breaker, as I can usually determine the correct placements by looking at the application code in the region and determining what makes sense, but it is something that would probably build up some irritation with time. Feature – Suggest Method for Optimization A neat feature to really help those in need of a pointer, is the menu option under tools to automatically suggest methods to optimize/improve: Nice feature – clicking it filters the call tree and stars methods that it thinks are good candidates for optimization.  I do wish that they would have made it more visible for those of use who aren’t great on sight: Process Integration I do think that this could have a place in my process.  After experimenting with the profiler, I do think it would be a great benefit to do some development, testing, and then after all the bugs are worked out, use the profiler to check on things to make sure nothing seems like it is hogging more than its fair share.  For example, with this program, I would have developed it, ran it, tested it – it works, but slowly. After looking at the profiler, and seeing the massive amount of time spent in 1 method, I might go ahead and try to re-implement IPrimes (I actually would probably rewrite the offending code, but so that I can distribute both sets of code easily, I’m just going to make another implementation of IPrimes).  Using two pieces of knowledge about prime numbers can make this method MUCH more efficient – prime numbers fall into two buckets 6k+/-1 , and a number is prime if it is not divisible by any other primes before it: public class SmartPrimes : IPrimes { public IEnumerable<int> GetPrimes(int retrieve) { //store a list of primes already found var _foundPrimes = new List<int>() { 2, 3 }; //if i ask for 1 or two primes, return what asked for if (retrieve <= _foundPrimes.Count()) return _foundPrimes.Take(retrieve); //the next number to look at int _k = 1; //since I already determined I don't have enough //execute at least once, and until quantity is sufficed do { //assume prime until otherwise determined bool isPrime = true; int potentialPrime; //analyze 6k-1 //assign the value to potential potentialPrime = 6 * _k - 1; //if there are any primes that divise this, it is NOT a prime number //using PLINQ for quick boost isPrime = !_foundPrimes.AsParallel() .Any(prime => potentialPrime % prime == 0); //if it is prime, add to found list if (isPrime) _foundPrimes.Add(potentialPrime); if (_foundPrimes.Count() == retrieve) break; //analyze 6k+1 //assign the value to potential potentialPrime = 6 * _k + 1; //if there are any primes that divise this, it is NOT a prime number //using PLINQ for quick boost isPrime = !_foundPrimes.AsParallel() .Any(prime => potentialPrime % prime == 0); //if it is prime, add to found list if (isPrime) _foundPrimes.Add(potentialPrime); //increment k to analyze next _k++; } while (_foundPrimes.Count() < retrieve); return _foundPrimes; } } Now there are definitely more things I can do to help make this more efficient, but for the scope of this example, I think this is fine (but still hideous)! Profiling this now yields a happy surprise 27 seconds to generate the 15000 primes with the profiler attached, and only 1.43 seconds without.  One important thing I wanted to call out though was the performance graph now: Notice anything odd?  The %Processor time is above 100%.  This is because there is now more than 1 core in the operation.  A better label for the chart in my mind would have been %Core time, but to each their own. Another odd thing I noticed was that the profiler seemed to be spot on this time in my DumbPrimes class with line details in source, even with comments..  Odd. Profiling Web Applications The last thing that I wanted to cover, that means a lot to me as a web developer, is the great amount of work that Red Gate put into the profiler when profiling web applications.  In my solution, I have a simple MVC4 application setup with 1 page, a single input form, that will output prime values as my WPF app did.  Launching the profiler from Visual Studio as before, nothing is really different in the profiler window, however I did receive a UAC prompt for a Red Gate helper app to integrate with the web server without notification. After requesting 500, 1000, 2000, and 5000 primes, and looking at the profiler session, things are slightly different from before: As you can see, there are 4 spikes of activity in the processor time graph, but there is also something new in the call tree: That’s right – ANTS will actually group method calls by get/post operations, so it is easier to find out what action/page is giving the largest problems…  Pretty cool in my mind! Overview Overall, I think that Red Gate ANTS CLR Profiler has a lot to offer, however I think it also has a long ways to go.  3 Biggest Pros: Ability to easily drill down from time graph, to method calls, to source code Wide variety of counters to choose from when profiling your application Excellent integration/grouping of methods being called from web applications by request – BRILLIANT! 3 Biggest Cons: Issue regarding line details in source view Nit pick – Processor time vs. Core time Nit pick – Lack of full integration with Visual Studio Ratings Ease of Use (7/10) – I marked down here because of the problems with the line level details and the extra work that that entails, and the lack of better integration with Visual Studio. Effectiveness (10/10) – I believe that the profiler does EXACTLY what it purports to do.  Especially with its large variety of performance counters, a definite plus! Features (9/10) – Besides the real time performance monitoring, and the drill downs that I’ve shown here, ANTS also has great integration with ADO.Net, with the ability to show database queries run by your application in the profiler.  This, with the line level details, the web request grouping, reflector integration, and various options to customize your profiling session I think create a great set of features! Customer Service (10/10) – My entire experience with Red Gate personnel has been nothing but good.  their people are friendly, helpful, and happy! UI / UX (8/10) – The interface is very easy to get around, and all of the options are easy to find.  With a little bit of poking around, you’ll be optimizing Hello World in no time flat! Overall (8/10) – Overall, I am happy with the Performance Profiler and its features, as well as with the service I received when working with the Red Gate personnel.  I WOULD recommend you trying the application and seeing if it would fit into your process, BUT, remember there are still some kinks in it to hopefully be worked out. My next post will definitely be shorter (hopefully), but thank you for reading up to here, or skipping ahead!  Please, if you do try the product, drop me a message and let me know what you think!  I would love to hear any opinions you may have on the product. Code Feel free to download the code I used above – download via DropBox

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