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  • For a set of sql-queries, how do you determine which result-set contains a certain row?

    - by ManBugra
    I have a set of sql - queries: List<String> queries = ... queries[0] = "select id from person where ..."; ... queries[8756] = "select id from person where ..."; Each query selects rows from the same table 'person'. The only difference is the where-clause. Table 'person' looks like this: id | name | ... many other columns How can i determine which queries will contain a certain person in their subset? For example: List<Integer> matchingQueries = magicMethod(queries, [23,45]); The list obtained by 'magicMethod' filters all sql queries present in the list 'queries' (defined above) and returns only those that contain either the person with id 23 OR a person with id 45. Why i need it: I am dealing with an application that contains products and categories where the categories are sql queries that define which products belong to them (queries stored in a table also). Now i have a requirement where an admin has to see all categories an item belongs to immediately after the item was created. Btw, over 8.000 categories defined (so far, more to come). language and db: java && postgreSQL Thanks,

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  • What is the proper way to use a Logger in a Serializable Java class?

    - by Tim Visher
    I have the following (doctored) class in a system I'm working on and Findbugs is generating a SE_BAD_FIELD warning and I'm trying to understand why it would say that before I fix it in the way that I thought I would. The reason I'm confused is because the description would seem to indicate that I had used no other non-serializable instance fields in the class but bar.model.Foo is also not serializable and used in the exact same way (as far as I can tell) but Findbugs generates no warning for it. import bar.model.Foo; import java.io.File; import java.io.Serializable; import java.util.List; import org.slf4j.Logger; import org.slf4j.LoggerFactory; public class Demo implements Serializable { private final Logger logger = LoggerFactory.getLogger(this.getClass()); private final File file; private final List<Foo> originalFoos; private Integer count; private int primitive = 0; public Demo() { for (Foo foo : originalFoos) { this.logger.debug(...); } } ... } My initial blush at a solution is to get a logger reference from the factory right as I use it: public DispositionFile() { Logger logger = LoggerFactory.getLogger(this.getClass()); for (Foo foo : originalFoos) { this.logger.debug(...); } } That doesn't seem particularly efficient, though. Thoughts?

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  • Design Philosophy Question - When to create new functions

    - by Eclyps19
    This is a general design question not relating to any language. I'm a bit torn between going for minimum code or optimum organization. I'll use my current project as an example. I have a bunch of tabs on a form that perform different functions. Lets say Tab 1 reads in a file with a specific layout, tab 2 exports a file to a specific location, etc. The problem I'm running into now is that I need these tabs to do something slightly different based on the contents of a variable. If it contains a 1 I may need to use Layout A and perform some extra concatenation, if it contains a 2 I may need to use Layout B and do no concatenation but add two integer fields, etc. There could be 10+ codes that I will be looking at. Is it more preferable to create an individual path for each code early on, or attempt to create a single path that branches out only when absolutely required. Creating an individual path for each code would allow my code to be extremely easy to follow at a glance, which in turn will help me out later on down the road when debugging or making changes. The downside to this is that I will increase the amount of code written by calling some of the same functions in multiple places (for example, steps 3, 5, and 9 for every single code may be exactly the same. Creating a single path that would branch out only when required will be a bit messier and more difficult to follow at a glance, but I would create less code by placing conditionals only at steps that are unique. I realize that this may be a case-by-case decision, but in general, if you were handed a previously built program to work on, which would you prefer?

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  • How to decrypt a string encrypted with HMACSHA1?

    - by Bob
    I'm an encryption novice trying to pass some values back and forth between systems. I can encrypt the value, but can't seem to figure out how to decrypt on the other end. I've created a simple Windows Forms application using VB.NET. Trying to input a value and a key, encrypt and then decrypt to get the original value. Here's my code so far. Any help greatly appreciated. Thanks. Imports System Imports System.IO Imports System.Security.Cryptography Imports System.Text Public Class Form1 Private Sub btnEncode_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnEncode.Click Dim hmacsha1 As New HMACSHA1(Encoding.ASCII.GetBytes(txtKey.Text)) Dim hashValue As Byte() = hmacsha1.ComputeHash(Encoding.ASCII.GetBytes(txtValue.Text)) txtResult.Text = BytesToHexString(hashValue) hmacsha1.Clear() End Sub Private Sub btnDecode_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnDecode.Click '??? End Sub Private Function BytesToHexString(ByVal bytes As Byte()) As String Dim output As String = String.Empty Dim i As Integer = 0 Do While i < bytes.Length output += bytes(i).ToString("X2") i += 1 Loop Return output End Function End Class

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  • Does Hibernate support one-to-one associations as pkeys?

    - by Andrzej Doyle
    Hi all, Can anyone tell me whether Hibernate supports associations as the pkey of an entity? I thought that this would be supported but I am having a lot of trouble getting any kind of mapping that represents this to work. In particular, with the straight mapping below: @Entity public class EntityBar { @Id @OneToOne(optional = false, mappedBy = "bar") EntityFoo foo // other stuff } I get an org.hibernate.MappingException: "Could not determine type for: EntityFoo, at table: ENTITY_BAR, for columns: [org.hibernate.mapping.Column(foo)]" Diving into the code it seems the ID is always considered a Value type; i.e. "anything that is persisted by value, instead of by reference. It is essentially a Hibernate Type, together with zero or more columns." I could make my EntityFoo a value type by declaring it serializable, but I wouldn't expect this would lead to the right outcome either. I would have thought that Hibernate would consider the type of the column to be integer (or whatever the actual type of the parent's ID is), just like it would with a normal one-to-one link, but this doesn't appear to kick in when I also declare it an ID. Am I going beyond what is possible by trying to combine @OneToOne with @Id? And if so, how could one model this relationship sensibly?

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  • Spring 3 MVC validation BindingResult doesn't contain any errors

    - by Travelsized
    I'm attempting to get a Spring 3.0.2 WebMVC project running with the new annotated validation support. I have a Hibernate entity annotated like this: @Entity @Table(name = "client") public class Client implements Serializable { private static final long serialVersionUID = 1L; @Id @Basic(optional = false) @Column(name = "clientId", nullable = false) @NotEmpty private Integer clientId; @Basic(optional = false) @Column(name = "firstname", nullable = false, length = 45) @NotEmpty @Size(min=2, max=45) private String firstname; ... more fields, getters and setters } I've turned on mvc annotation support in my applicationContext.xml file: <mvc:annotation-driven /> And I have a method in my controller that responds to a form submission: @RequestMapping(value="/addClient.htm") public String addClient(@ModelAttribute("client") @Valid Client client, BindingResult result) { if(result.hasErrors()) { return "addClient"; } service.storeClient(client); return "clientResult"; } When my app loads in the server, I can see in the server log file that it loads a validator: 15 [http-8084-2] INFO org.hibernate.validator.util.Version - Hibernate Validator 4.0.2.GA The problem I'm having is that the validator doesn't seem to kick in. I turned on the debugger, and when I get into the controller method, the BindingResult contains 0 errors after I submit an empty form. (The BindingResult does show that it contains the Client object as a target.) It then proceeds to insert a record without an Id and throws an exception. If I fill out an Id but leave the name blank, it creates a record with the Id and empty fields. What steps am I missing to get the validation working?

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  • minimum L sum in a mxn matrix - 2

    - by hilal
    Here is my first question about maximum L sum and here is different and hard version of it. Problem : Given a mxn *positive* integer matrix find the minimum L sum from 0th row to the m'th row . L(4 item) likes chess horse move Example : M = 3x3 0 1 2 1 3 2 4 2 1 Possible L moves are : (0 1 2 2), (0 1 3 2) (0 1 4 2) We should go from 0th row to the 3th row with minimum sum I solved this with dynamic-programming and here is my algorithm : 1. Take a mxn another Minimum L Moves Sum array and copy the first row of main matrix. I call it (MLMS) 2. start from first cell and look the up L moves and calculate it 3. insert it in MLMS if it is less than exists value 4. Do step 2. until m'th row 5. Choose the minimum sum in the m'th row Let me explain on my example step by step: M[ 0 ][ 0 ] sum(L1 = (0, 1, 2, 2)) = 5 ; sum(L2 = (0,1,3,2)) = 6; so MLMS[ 0 ][ 1 ] = 6 sum(L3 = (0, 1, 3, 2)) = 6 ; sum(L4 = (0,1,4,2)) = 7; so MLMS[ 2 ][ 1 ] = 6 M[ 0 ][ 1 ] sum(L5 = (1, 0, 1, 4)) = 6; sum(L6 = (1,3,2,4)) = 10; so MLMS[ 2 ][ 2 ] = 6 ... the last MSLS is : 0 1 2 4 3 6 6 6 6 Which means 6 is the minimum L sum that can be reach from 0 to the m. I think it is O(8*(m-1)*n) = O(m*n). Is there any optimal solution or dynamic-programming algorithms fit this problem? Thanks, sorry for long question

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  • Noob - Cycle through stored names and skip blanks

    - by ActiveJimBob
    NOOB trying to make my code more efficient. On scroll button push, the function 'SetName' stores a number to integer 'iName' which is index against 5 names stored in memory. If a name is not set in memeory, it skips to the next. The code works, but takes up a lot of room. Any advice appreciated. Code: #include <string.h> int iName = 0; int iNewName = 0; BYTE GetName () { return iName; } void SetName (int iNewName) { while (iName != iNewName) { switch (byNewName) { case 1: if (strlen (memory.m_nameA) == 0) new_name++; else iName = iNewName; break; case 2: if (strlen (memory.m_nameB) == 0) new_name++; else iName = iNewName; break; case 3: if (strlen (memory.m_nameC) == 0) new_name++; else iName = iNewName; break; case 4: if (strlen (memory.m_nameD) == 0) new_name++; else iName = iNewName; break; case 5: if (strlen (memory.m_nameE) == 0) new_name++; else iName = iNewName; break; default: iNewName = 1; break; } // end of case } // end of loop } // end of SetName function void main () { while(1) { if (Button_pushed) SetName(GetName+1); } // end of infinite loop } // end of main

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  • computes the number of possible orderings of n objects under the relations < and =

    - by hilal
    Here is the problem : Give a algorithm that takes a positive integer n as input, and computes the number of possible orderings of n objects under the relations < and =. For example, if n = 3 the 13 possible orderings are as follows: a = b = c, a = b < c, a < b = c, a < b < c, a < c < b, a = c < b, b < a = c, b < a < c, b < c < a, b = c < a, c < a = b, c < a < b, c < b < a. Your algorithm should run in time polynomial in n. I'm null to this problem. Can you find any solution to this dynamic-programming problem?

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  • Why can't I start the Windows Update control panel with WinExec?

    - by Bill
    In Executing Control Panel Items, MSDN says this: Windows Vista Canonical Names In Windows Vista and later, the preferred method of launching a Control Panel item from a command line is to use the Control Panel item's canonical name. According to the Microsoft website this should work: The following example shows how an application can start the Control Panel item Windows Update with WinExec. WinExec("%systemroot%\system32\control.exe /name Microsoft.WindowsUpdate", SW_NORMAL); For Delphi 2010 I tried: var CaptionString: string; Applet: string; Result: integer; ParamString: string; CaptionString := ListviewApplets1.Items.Item[ ListviewApplets1.ItemIndex ].Caption; if CaptionString = 'Folder Options' then { 6DFD7C5C-2451-11d3-A299-00C04F8EF6AF } Applet := 'Microsoft.FolderOptions' else if CaptionString = 'Fonts' then {93412589-74D4-4E4E-AD0E-E0CB621440FD} Applet := 'Microsoft.Fonts' else if CaptionString = 'Windows Update' then { 93412589-74D4-4E4E-AD0E-E0CB621440FD } Applet := 'Microsoft.WindowsUpdate' else if CaptionString = 'Game Controllers' then { 259EF4B1-E6C9-4176-B574-481532C9BCE8 } Applet := 'Microsoft.GameControllers' else if CaptionString = 'Get Programs' then { 15eae92e-f17a-4431-9f28-805e482dafd4 } Applet := 'Microsoft.GetPrograms' //... ParamString := ( SystemFolder + '\control.exe /name ' ) + Applet; WinExec( ParamString, SW_NORMAL); <= This does not execute and when I trapped the error it returned ERROR_FILE_NOT_FOUND. I tried a ExecAndWait( ParamString ) method and it works perfectly with the same ParamString used with WinExec: ParamString := ( SystemFolder + '\control.exe /name ' ) + Applet; ExecAndWait( ParamString ); <= This executes and Runs perfectly The ExecAndWait method I used calls Windows.CreateProcess: if Windows.CreateProcess( nil, PChar( CommandLine ), nil, nil, False, 0, nil, nil, StartupInfo, ProcessInfo ) then begin try Does WinExec require a different ParamString, or am I doing this wrong with WinExec? I did not post the full ExecAndWait method but I can if someone wants to see it.

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  • RTTI Dynamic array TValue Delphi 2010

    - by user558126
    Hello I have a question. I am a newbie with Run Time Type Information from Delphi 2010. I need to set length to a dynamic array into a TValue. You can see the code. Type TMyArray = array of integer; TMyClass = class publihed function Do:TMyArray; end; function TMyClass.Do:TMyArray; begin SetLength(Result,5); for i:=0 to 4 Result[i]=3; end; ....... ....... ...... y:TValue; Param:array of TValue; ......... y=Methods[i].Invoke(Obj,Param);//delphi give me a DynArray type kind, is working, Param works to any functions. if Method[i].ReturnType.TypeKind = tkDynArray then//is working... begin I want to set length for y to 10000//i don't know how to write. end; I don't like Generics Collections.

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  • How to properly implement the Strategy pattern in a web MVC framework?

    - by jboxer
    In my Django app, I have a model (lets call it Foo) with a field called "type". I'd like to use Foo.type to indicate what type the specific instance of Foo is (possible choices are "Number", "Date", "Single Line of Text", "Multiple Lines of Text", and a few others). There are two things I'd like the "type" field to end up affecting; the way a value is converted from its normal type to text (for example, in "Date", it may be str(the_date.isoformat())), and the way a value is converted from text to the specified type (in "Date", it may be datetime.date.fromtimestamp(the_text)). To me, this seems like the Strategy pattern (I may be completely wrong, and feel free to correct me if I am). My question is, what's the proper way to code this in a web MVC framework? In a client-side app, I'd create a Type class with abstract methods "serialize()" and "unserialize()", override those methods in subclasses of Type (such as NumberType and DateType), and dynamically set the "type" field of a newly-instantiated Foo to the appropriate Type subclass at runtime. In a web framework, it's not quite as straightforward for me. Right now, the way that makes the most sense is to define Foo.type as a Small Integer field and define a limited set of choices (0 = "Number", 1 = "Date", 2 = "Single Line of Text", etc.) in the code. Then, when a Foo object is instantiated, use a Factory method to look at the value of the instance's "type" field and plug in the correct Type subclass (as described in the paragraph above). Foo would also have serialize() and unserialize() methods, which would delegate directly to the plugged-in Type subclass. How does this design sound? I've never run into this issue before, so I'd really like to know if other people have, and how they've solved it.

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  • Java: ResultSet exception - before start of result set

    - by Rosarch
    I'm having trouble getting data from a ResultSet object. Here is my code: String sql = "SELECT type FROM node WHERE nid = ?"; PreparedStatement prep = conn.prepareStatement(sql); int meetNID = Integer.parseInt(node.get(BoutField.field_meet_nid)); prep.setInt(1, meetNID); ResultSet result = prep.executeQuery(); result.beforeFirst(); String foundType = result.getString(1); if (! foundType.equals("meet")) { throw new IllegalArgumentException(String.format("Node %d must be of type 'meet', but was %s", meetNID, foundType)); } The error trace: Exception in thread "main" java.sql.SQLException: Before start of result set at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:1072) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:986) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:981) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:926) at com.mysql.jdbc.ResultSetImpl.checkRowPos(ResultSetImpl.java:841) at com.mysql.jdbc.ResultSetImpl.getStringInternal(ResultSetImpl.java:5656) at com.mysql.jdbc.ResultSetImpl.getString(ResultSetImpl.java:5576) at nth.cumf3.nodeImport.Validator.validate(Validator.java:43) at nth.cumf3.nodeImport.Main.main(Main.java:38) What am I doing wrong here?

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  • Referencing not-yet-defined variables - Java

    - by user2537337
    Because I'm tired of solving math problems, I decided to try something more engaging with my very rusty (and even without the rust, very basic) Java skills. I landed on a super-simple people simulator, and thus far have been having a grand time working through the various steps of getting it to function. Currently, it generates an array of people-class objects and runs a for loop to cycle through a set of actions that alter the relationships between them, which I have stored in a 2d integer array. When it ends, I go look at how much they all hate each other. Fun stuff. Trouble has arisen, however, because I would like the program to clearly print what action is happening when it happens. I thought the best way to do this would be to add a string, description, to my "action" class (which stores variables for the actor, reactor, and the amount the relationship changes). This works to a degree, in that I can print a generic message ("A fight has occurred!") with no problem. However, ideally I would like it to be a little more specific ("Person A has thrown a rock at Person B's head!"). This latter goal is proving more difficult: attempting to construct an action with a description string that references actor and reactor gets me a big old error, "Cannot reference field before it is defined." Which makes perfect sense. I believe I'm not quite in programmer mode, because the only other way I can think to do this is an unwieldy switch statement that negates the need for each action to have its own nicely-packaged description. And there must be a neater way. I am not looking for examples of code, only a push in the direction of the right concept to handle this.

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  • Slope requires a real as parameter 2?

    - by Dave Jarvis
    Question How do you pass the correct value to udf_slope's second parameter type? Attempts CAST(Y.YEAR AS FLOAT), but that failed (SQL error). Y.YEAR + 0.0, but that failed, too (see error message). slope(D.AMOUNT, 1.0), failed as well Error Message Using udf_slope fails due to: Can't initialize function 'slope'; slope() requires a real as parameter 2 Code SELECT D.AMOUNT, Y.YEAR, slope(D.AMOUNT, Y.YEAR + 0.0) as SLOPE, intercept(D.AMOUNT, Y.YEAR + 0.0) as INTERCEPT FROM YEAR_REF Y, DAILY D Here, D.AMOUNT is a FLOAT and Y.YEAR is an INTEGER. Create Function The slope function was created as follows: CREATE AGGREGATE FUNCTION slope RETURNS REAL SONAME 'udf_slope.so'; Function Signature From udf_slope.cc: double slope( UDF_INIT* initid, UDF_ARGS* args, char* is_null, char* is_error ) Example Usages Reading the fine manual reveals: UDF intercept() Calculates the intercept of the linear regression of two sets of variables. Function name intercept Input parameter(s) 2 (dependent variable: REAL, independent variable: REAL) Examples SELECT intercept(income,age) FROM customers UDF slope() Calculates the slope of the linear regression of two sets of variables. Function name slope Input parameter(s) 2 (dependent variable: REAL, independent variable: REAL) Examples SELECT slope(income,age) FROM customers Thoughts? Thank you!

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  • How to visually reject user input in a table?

    - by FX
    In the programming of a table-based application module (i.e. the user mostly enters tabular data in an already laid-out table), how would you reject user input for a given cell? The scenario is: the user edits the cell, enters something (text, picture, ...) and you want them to notice when they finish editing (hitting enter, for example) that their entry is not valid for your given "format" (in the wider meaning: it can be that they entered a string instead of a number, that their entry is too long, too short, they include a picture while it's not acceptable, ...). I can see two different things happening: You can rather easily fit their entry into your format, and you do so, but you want them to notice it so they can change if your guess is not good enough (example: they entered "15.47" in a field that needs to be an integer, so your program makes it "15") You cannot guess what to do with their entry, and want to inform them that it's not valid. My question specifically is: what visual display can you offer to inform the user that his input is invalid? Is it preferable to refuse to leave the editing mode, or not? The two things I can imagine are: using colors (red background if invalid, yellow background for my case 1 above) when you reject an input, do something like Apple does for password entry of user accounts: you make the cell "shaking" (i.e. oscillating left and right) for one second, and keep the focus/editing in their so they don't loose what they've typed. Let's hear your suggestions. PS: This question is, at least in my thought process, somehow a continuation and a specialization of my previous question on getting users to read error messages. PPS: Made this community wiki, was that the right thing to do on this kind of question or not?

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  • How do i access EJB implementing remote interface in separate web application?

    - by Nitesh Panchal
    Hello, I am using Netbeans 6.8 and Glassfish v3.0. I created an ejb module and created entity classes from database and then created stateless session bean with remote interface. Say eg. @Remote public interface customerRemote{ public void add(String name, String address); public Customer find(Integer id); } @Stateless public class customerBean implements customerRemote{ //implementations of methods } Then i created a new web application. But now how do i access remote ejb's in my web application. I could lookup a bean with jndi name but what i want to know is, what type of object it will return? How do i typecast it in customerRemote? I don't have any class named customerRemote in my web application. So, how do i do it? Also, what about the entity class Customer? There is no such class named Customer in my web application also. All ejb's and entity classes are in separate ejb module. Please help me :(

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  • What's a clean way to have the server return a JavaScript function which would then be invoked?

    - by Khnle
    My application is architected as a host of plug-ins that have not yet been written. There's a long reason for this, but with each new year, the business logic will be different and we don't know what it will be like (Think of TurboTax if that helps). The plug-ins consist of both server and client components. The server components deals with business logic and persisting the data into database tables which will be created at a later time as well. The JavaScript manipulates the DOM for the browsers to render afterward. Each plugin lives in a separate assembly, so that they won't disturb the main application, i.e., we don't want to recompile the main application. Long story short, I am looking for a way to return JavaScript functions to the client from an Ajax get request, and execute these JavaScript functions (which are just returned). Invoking a function in Javascript is easy. The hard part is how to organize or structure so that I won't have to deal with maintenance problem. So concat using StringBuilder to end up with JavaScript code as a result of calling toString() from the string builder object is out of the question. I want to have no difference between writing JavaScript codes normally and writing Javascript codes for this dynamic purpose. An alternative is to manipulate the DOM on the server side, but I doubt that it would be as elegantly as using jQuery on the client side. I am open for a C# library that supports chainable calls like jQuery that also manipulates the DOM too. Do you have any idea or is it too much to ask or are you too confused? Edit1: The point is to avoid recompiling, hence the plug-ins architecture. In some other parts of the program, I already use the concept of dynamically loading Javascript files. That works fine. What I am looking here is somewhere in the middle of the program when an Ajax request is sent to the server. Edit 2: To illustrate my question: Normally, you would see the following code. An Ajax request is sent to the server, a JSON result is returned to the client which then uses jQuery to manipulate the DOM (creating tag and adding to the container in this case). $.ajax({ type: 'get', url: someUrl, data: {'': ''}, success: function(data) { var ul = $('<ul>').appendTo(container); var decoded = $.parseJSON(data); $.each(decoded, function(i, e) { var li = $('<li>').text(e.FIELD1 + ',' + e.FIELD2 + ',' + e.FIELD3); ul.append(li); }); } }); The above is extremely simple. But next year, what the server returns is totally different and how the data to be rendered would also be different. In a way, this is what I want: var container = $('#some-existing-element-on-the-page'); $.ajax({ type: 'get', url: someUrl, data: {'': ''}, success: function(data) { var decoded = $.parseJSON(data); var fx = decoded.fx; var data = decode.data; //fx is the dynamic function that create the DOM from the data and append to the existing container fx(container, data); } }); I don't need to know, at this time what data would be like, but in the future I will, and I can then write fx accordingly.

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  • Alternatives to static methods on interfaces for enforcing consistency

    - by jayshao
    In Java, I'd like to be able to define marker interfaces, that forced implementations to provide static methods. For example, for simple text-serialization/deserialization I'd like to be able to define an interface that looked something like this: public interface TextTransformable<T>{ public static T fromText(String text); public String toText(); Since interfaces in Java can't contain static methods though (as noted in a number of other posts/threads: here, here, and here this code doesn't work. What I'm looking for however is some reasonable paradigm to express the same intent, namely symmetric methods, one of which is static, and enforced by the compiler. Right now the best we can come up with is some kind of static factory object or generic factory, neither of which is really satisfactory. Note: in our case our primary use-case is we have many, many "value-object" types - enums, or other objects that have a limited number of values, typically carry no state beyond their value, and which we parse/de-parse thousands of time a second, so actually do care about reusing instances (like Float, Integer, etc.) and its impact on memory consumption/g.c. Any thoughts?

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  • create and write to a text file in vb.net

    - by woolardz
    I'm creating a small vb.net application, and I'm trying trying to write a list of results from a listview to a text file. I've looked online and found the code to open the save file dialog and write the text file. When I click save on the save file dialog, I receive an IOException with the message "The process cannot access the file 'C:\thethe.txt' because it is being used by another process." The text file is created in the correct location, but is empty. The application quits at this line "Dim fs As New FileStream(saveFileDialog1.FileName, FileMode.OpenOrCreate, FileAccess.Write)" Thanks in advance for any help. Private Sub btnSave_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnSave.Click Dim myStream As Stream Dim saveFileDialog1 As New SaveFileDialog() saveFileDialog1.Filter = "txt files (*.txt)|*.txt|All files (*.*)|*.*" saveFileDialog1.FilterIndex = 2 saveFileDialog1.RestoreDirectory = True If saveFileDialog1.ShowDialog() = DialogResult.OK Then myStream = saveFileDialog1.OpenFile() If (myStream IsNot Nothing) Then Dim fs As New FileStream(saveFileDialog1.FileName, FileMode.OpenOrCreate, FileAccess.Write) Dim m_streamWriter As New StreamWriter(fs) m_streamWriter.Flush() 'Write to the file using StreamWriter class m_streamWriter.BaseStream.Seek(0, SeekOrigin.Begin) 'write each row of the ListView out to a tab-delimited line in a file For i As Integer = 0 To Me.ListView1.Items.Count - 1 m_streamWriter.WriteLine(((ListView1.Items(i).Text & vbTab) + ListView1.Items(i).SubItems(0).ToString() & vbTab) + ListView1.Items(i).SubItems(1).ToString()) Next myStream.Close() End If End If End Sub

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  • Inserting variables into a query string - it won't work!

    - by Jonesy
    Basically i have a query string that when i hardcode in the catalogue value its fine. when I try adding it via a variable it just doesn't pick it up. This works: Dim WaspConnection As New SqlConnection("Data Source=JURA;Initial Catalog=WaspTrackAsset_NROI;User id=" & ConfigurationManager.AppSettings("WASPDBUserName") & ";Password='" & ConfigurationManager.AppSettings("WASPDBPassword").ToString & "';") This doesn't: Public Sub GetWASPAcr() connection.Open() Dim dt As New DataTable() Dim username As String = HttpContext.Current.User.Identity.Name Dim sqlCmd As New SqlCommand("SELECT WASPDatabase FROM dbo.aspnet_Users WHERE UserName = '" & username & "'", connection) Dim sqlDa As New SqlDataAdapter(sqlCmd) sqlDa.Fill(dt) If dt.Rows.Count > 0 Then For i As Integer = 0 To dt.Rows.Count - 1 If dt.Rows(i)("WASPDatabase") Is DBNull.Value Then WASP = "" Else WASP = "WaspTrackAsset_" + dt.Rows(i)("WASPDatabase") End If Next End If connection.Close() End Sub Dim WaspConnection As New SqlConnection("Data Source=JURA;Initial Catalog=" & WASP & ";User id=" & ConfigurationManager.AppSettings("WASPDBUserName") & ";Password='" & ConfigurationManager.AppSettings("WASPDBPassword").ToString & "';") When I debug the catalog is empty in the query string but the WASP variable holds the value "WaspTrackAsset_NROI" Any idea's why? Cheers, jonesy

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  • Php - divide time period into equal intervals

    - by experc
    Hi! I am working on my php course project and for the past few days I have stucked at the point where I have to create php function which gets 5 parameters which represents information about the working time of some department - when the work starts/ends, when the lunchtime (or any other break) starts/ends and integer representing minutes into how small piecies we should divide time period. Besides - it's possible that there are not any breaks in the working time. The function should return all intervals from working time. function split_time_into_intervals($work_starts,$work_ends,$break_starts=null; $break_ends=null,$minutes_per_interval=60){ $intervals=array(); //all of the function code return $intervals; } So if I have the following parameters for the function function split_time_into_intervals("8:30","14:50","11:45"; "12:25"){ .. } I would like to retrieve the following array: $intervals[0]['starts']="8:30"; $intervals[0]['ends']="9:30"; $intervals[1]['starts']="9:30"; $intervals[1]['ends']="10:30"; $intervals[2]['starts']="10:30"; $intervals[2]['ends']="11:30"; $intervals[3]['starts']="11:30"; $intervals[3]['ends']="11:45"; //this interval was smaller than 60 minutes - because of the break (which starts at 11:45) $intervals[4]['starts']="12:25";//starts when the break ends $intervals[4]['ends']="13:25"; // interval is again 60 minutes $intervals[5]['starts']="13:25"; $intervals[5]['ends']="14:25"; $intervals[6]['starts']="14:25"; $intervals[6]['ends']="14:50"; //this period is shorter than 60 minutes - because work ends Any advises? I would apriciate any php (or C#) code regarding to this problem!

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  • Speed of QHash lookups using QStrings as keys.

    - by Ryan R.
    I need to draw a dynamic overlay on a QImage. The component parts of the overlay are defined in XML and parsed out to a QHash<QString, QPicture> where the QString is the name (such as "crosshairs") and the QPicture is the resolution independent drawing. I then draw components of the overlay as they are needed at a position determined during runtime. Example: I have 10 pictures in my QHash composing every possible element in a HUD. During a particular frame of video I need to draw 6 of them at different positions on the image. During the next frame something has changed and now I only need to draw 4 of them but 2 of those positions have changed. Now to my question: If I am trying to do this quickly, should I redefine my QHash as QHash<int, QPicture> and enumerate the keys to counteract the overhead caused by string comparisons; or are the comparisons not going to make a very big impact on performance? I can easily make the conversion to integer keys as the XML parser and overlay composer are completely separate classes; but I would like to use a consistent data structure across the application. Should I overcome my desire for consistency and re-usability in order to increase performance? Will it even matter very much if I do?

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  • can a python script know that another instance of the same script is running... and then talk to it?

    - by Justin Grant
    I'd like to prevent multiple instances of the same long-running python command-line script from running at the same time, and I'd like the new instance to be able to send data to the original insance before the new instance commits suicide. How can I do this in a cross-platform way? Specifically, I'd like to enable the following behavior: "foo.py" is launched from the command line, and it will stay running for a long time-- days or weeks until the machine is rebooted or the parent process kills it. every few minutes the same script is launched again, but with different command-line parameters when launched, the script should see if any other instances are running. if other instances are running, then instance #2 should send its command-line parameters to instance #1, and then instance #2 should exit. instance #1, if it receives command-line parameters from another script, should spin up a new thread and (using the command-line parameters sent in the step above) start performing the work that instance #2 was going to perform. So I'm looking for two things: how can a python program know another instance of itself is running, and then how can one python command-line program communicate with another? Making this more complicated, the same script needs to run on both Windows and Linux, so ideally the solution would use only the Python standard library and not any OS-specific calls. Although if I need to have a Windows codepath and an *nix codepath (and a big if statement in my code to choose one or the other), that's OK if a "same code" solution isn't possible. I realize I could probably work out a file-based approach (e.g. instance #1 watches a directory for changes and each instance drops a file into that directory when it wants to do work) but I'm a little concerned about cleaning up those files after a non-graceful machine shutdown. I'd ideally be able to use an in-memory solution. But again I'm flexible, if a persistent-file-based approach is the only way to do it, I'm open to that option. More details: I'm trying to do this because our servers are using a monitoring tool which supports running python scripts to collect monitoring data (e.g. results of a database query or web service call) which the monitoring tool then indexes for later use. Some of these scripts are very expensive to start up but cheap to run after startup (e.g. making a DB connection vs. running a query). So we've chosen to keep them running in an infinite loop until the parent process kills them. This works great, but on larger servers 100 instances of the same script may be running, even if they're only gathering data every 20 minutes each. This wreaks havoc with RAM, DB connection limits, etc. We want to switch from 100 processes with 1 thread to one process with 100 threads, each executing the work that, previously, one script was doing. But changing how the scripts are invoked by the monitoring tool is not possible. We need to keep invocation the same (launch a process with different command-line parameters) but but change the scripts to recognize that another one is active, and have the "new" script send its work instructions (from the command line params) over to the "old" script.

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  • pointer in c and the c program

    - by sandy101
    Hello, I am studying the pointer and i come to this program .... #include <stdio.h> void swap(int *,int *); int main() { int a=10; int b=20; swap(&a,&b); printf("the value is %d and %d",a,b); return 0; } void swap(int *a,int*b) { int t; t=*a; *a=*b; *b=t; printf("%d and%d\n",*a,*b); } can any one tell me why this main function return the value reversed . The thing i understood till now is that the function call in c does not affect the main function and it's values . I also want to know how much the space a pointer variable occupied like integer have occupied the 2 bytes and the various application use and advantages of the pointer .... plz.... anyone help

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