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• c++ networking issue- retrnsmittion without ccongestion

  - by gln

  I wrote an application in c++ which send data over tcp connection to several machines.as part of the protocol I use in my application, the other side sends hearbeat messages from time to time, then I know that the connection is still alive. now, I want this application to work on 100 machines or more at the same time. but, I see that sometimes I don't get these heartbeat messages although they sent: I see in wireshark that the packet arrived, then my OS doesn't ack on this message, so there are some retransmit without any ack from my OS. if I look in the window size property - I saw that there is no issue in this part. what can be the root cause for this behavior? it is something in my code that I should change? this is my select code: int res = select(fdCount, &readFds, NULL, NULL, NULL ); I'm using server 2008 r2. Please help me! thanks

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• connecting clients to server with emulator on different computers

  - by prolink007

  I am writing an application that communicates using sockets. I have a server running on one android emulator on a computer, then i have 2 other clients running on android emulators on 2 other computers. I am trying to get the 2 clients to connect to the server. This works when i run the server and clients on the same computer, but when i attempt to do this on the same wifi network and on separate computers it gives me the following error. The client and server code is posted below. A lot is stripped out just to show the important stuff. Also, after the server starts i telnet into the server and run these commands redir add tcp:5000:6000 (i have also tried without doing the redir but it still says the same thing). Then i start the clients and get the error. Thanks for the help! Both the 5000 port and 6000 port are open on my router. And i have windows firewall disabled on the computer hosting the server. 11-27 18:54:02.274: W/ActivityManager(60): Activity idle timeout for HistoryRecord{44cf0a30 school.cpe434.ClassAidClient/school.cpe434.ClassAid.ClassAidClient4Activity} 11-27 18:57:02.424: W/System.err(205): java.net.SocketException: The operation timed out 11-27 18:57:02.454: W/System.err(205): at org.apache.harmony.luni.platform.OSNetworkSystem.connectSocketImpl(Native Method) 11-27 18:57:02.454: W/System.err(205): at org.apache.harmony.luni.platform.OSNetworkSystem.connect(OSNetworkSystem.java:114) 11-27 18:57:02.465: W/System.err(205): at org.apache.harmony.luni.net.PlainSocketImpl.connect(PlainSocketImpl.java:245) 11-27 18:57:02.465: W/System.err(205): at org.apache.harmony.luni.net.PlainSocketImpl.connect(PlainSocketImpl.java:220) 11-27 18:57:02.465: W/System.err(205): at java.net.Socket.startupSocket(Socket.java:780) 11-27 18:57:02.465: W/System.err(205): at java.net.Socket.<init>(Socket.java:314) 11-27 18:57:02.465: W/System.err(205): at school.cpe434.ClassAid.ClassAidClient4Activity.onCreate(ClassAidClient4Activity.java:102) 11-27 18:57:02.474: W/System.err(205): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047) 11-27 18:57:02.474: W/System.err(205): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2459) 11-27 18:57:02.474: W/System.err(205): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2512) 11-27 18:57:02.474: W/System.err(205): at android.app.ActivityThread.access$2200(ActivityThread.java:119) 11-27 18:57:02.474: W/System.err(205): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1863) 11-27 18:57:02.474: W/System.err(205): at android.os.Handler.dispatchMessage(Handler.java:99) 11-27 18:57:02.474: W/System.err(205): at android.os.Looper.loop(Looper.java:123) 11-27 18:57:02.486: W/System.err(205): at android.app.ActivityThread.main(ActivityThread.java:4363) 11-27 18:57:02.486: W/System.err(205): at java.lang.reflect.Method.invokeNative(Native Method) 11-27 18:57:02.486: W/System.err(205): at java.lang.reflect.Method.invoke(Method.java:521) 11-27 18:57:02.486: W/System.err(205): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:860) 11-27 18:57:02.486: W/System.err(205): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:618) 11-27 18:57:02.486: W/System.err(205): at dalvik.system.NativeStart.main(Native Method) The server code public class ClassAidServer4Activity extends Activity { ServerSocket ss = null; String mClientMsg = ""; String mClientExtraMsg = ""; Thread myCommsThread = null; public static final int SERVERPORT = 6000; @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); TextView tv = (TextView) findViewById(R.id.textView1); tv.setText("Nothing from client yet"); this.myCommsThread = new Thread(new CommsThread()); this.myCommsThread.start(); } class CommsThread implements Runnable { public void run() { // Socket s = null; try { ss = new ServerSocket(SERVERPORT ); } catch (IOException e1) { // TODO Auto-generated catch block e1.printStackTrace(); } while(true) { try { Socket socket = ss.accept(); connectedDeviceCount++; Thread lThread = new Thread(new ListeningThread(socket)); lThread.start(); } catch (IOException e) { e.printStackTrace(); } } } } class ListeningThread implements Runnable { private Socket s = null; public ListeningThread(Socket socket) { // TODO Auto-generated constructor stub this.s = socket; } @Override public void run() { // TODO Auto-generated method stub while (!Thread.currentThread().isInterrupted()) { Message m = new Message(); // m.what = QUESTION_ID; try { if (s == null) s = ss.accept(); BufferedReader input = new BufferedReader( new InputStreamReader(s.getInputStream())); String st = null; st = input.readLine(); String[] temp = parseReadMessage(st); mClientMsg = temp[1]; if(temp.length > 2) { mClientExtraMsg = temp[2]; } m.what = Integer.parseInt(temp[0]); myUpdateHandler.sendMessage(m); } catch (IOException e) { e.printStackTrace(); } } } } } The client code public class ClassAidClient4Activity extends Activity { //telnet localhost 5554 //redir add tcp:5000:6000 private Socket socket; private String serverIpAddress = "192.168.1.102"; private static final int REDIRECTED_SERVERPORT = 5000; @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); try { InetAddress serverAddr = InetAddress.getByName(serverIpAddress); socket = new Socket(serverAddr, REDIRECTED_SERVERPORT); } catch (UnknownHostException e1) { mQuestionAdapter.add("UnknownHostException"); e1.printStackTrace(); } catch (IOException e1) { mQuestionAdapter.add("IOException"); e1.printStackTrace(); } } }

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• How can I search for a string in a .txt file for NSScanner?

  - by pixelbitapps

  I currently have the following code to get a certain piece of code from the UIWebView: NSURL *requestTimetableURL = [NSURL URLWithString:@"http://www.dhsb.org/index.phtml?d=201435"]; NSLog(@"Loaded Timetable"); NSError *error; NSString *page = [NSString stringWithContentsOfURL:requestTimetableURL encoding:NSASCIIStringEncoding error:&error]; [webView loadHTMLString:page baseURL:requestTimetableURL]; NSString* Period1; NSScanner *htmlScanner = [NSScanner scannerWithString:page]; [htmlScanner scanUpToString:@"<P align=center><STRONG><FONT color=#c00000>" intoString:NULL]; [htmlScanner scanString:@"<P align=center><STRONG><FONT color=#c00000>" intoString:NULL]; [htmlScanner scanUpToString:@"</FONT>" intoString:&Period1]; How can I scan a .txt file (which contains the string like above) for the code? E.G. [htmlScanner scanUpToString:teststring intoString:NULL]; Thanks!

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• Please help me in creating an update query

  - by Rajesh Rolen- DotNet Developer

  I have got a table which contains 5 column and query requirements: update row no 8 (or id=8) set its column 2, column 3's value from id 9th column 2, column 3 value. means all value of column 2, 3 should be shifted to column 2, 3 of upper row (start from row no 8) and value of last row's 2, 3 will be null For example, with just 3 rows, the first row is untouched, the second to N-1th rows are shifted once, and the Nth row has nulls. id math science sst hindi english 1 11 12 13 14 15 2 21 22 23 24 25 3 31 32 33 34 35 The result of query of id=2 should be: id math science sst hindi english 1 11 12 13 14 15 2 31 32 23 24 25 //value of 3rd row (col 2,3) shifted to row 2 3 null null 33 34 35 This process should run for all rows whose id 2 Please help me to create this update query I am using MS sqlserver 2005

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• get the current loacation (gps/wifi)

  - by gilmad

  i'm trying to get my location using it like this: LocationManager myLocationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE); Criteria criteria = new Criteria(); criteria.setAccuracy(Criteria.ACCURACY_FINE); criteria.setAltitudeRequired(false); criteria.setBearingRequired(false); criteria.setCostAllowed(true); criteria.setPowerRequirement(Criteria.POWER_LOW); String provider = myLocationManager.getBestProvider(criteria,true); if (provider != null) { //there is a provider myLocationManager.requestLocationUpdates(provider, 10L, 500.0f, (LocationListener) mainContext); Location myCurLocation = myLocationManager.getLastKnownLocation(provider); //here i'm trying to get some data from the //myCurLocation but //myCurLocation == NULL } but the myCurLocation is always == NULL what am I doing wrong??

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• error string list handle in C#

  - by Chelsea_cole

  Same namespace: 2 forms. public class Account //frm1 { public string Username; public string Password; } public class ListAcc { public static List<Account> UserList; } private void button1_Click(object sender, EventArgs e) { List<Account> UserList = new List<Account>(); Account acc = new Account(); acc.Username = textBox1.Text; acc.Password = textBox2.Text; UserList.Add(acc); } private void button2_Click(object sender, EventArgs e) //frm2 { string p = frmDangky.ListAcc.UserList[0].Username; // null ->error string p = frmDangky.ListAcc.UserList[0].Password; // null ->error } Someone help me? :( why my string is NULL???????? The textBox is not empty... Thanks!

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• Boost::asio bug in MSVC10 - Failing BOOST_WORKAROUND in ~buffer_debug_check() in buffer.hpp

  - by shaz

  A straight compilation of example http://www.boost.org/doc/libs/1_43_0/doc/html/boost_asio/tutorial/tutdaytime3/src.html results in a runtime null pointer exception. Stack trace points to the buffer_debug_check destructor which contains this comment: // MSVC's string iterator checking may crash in a std::string::iterator // object's destructor when the iterator points to an already-destroyed // std::string object, unless the iterator is cleared first. The test #if BOOST_WORKAROUND(BOOST_MSVC, = 1400) succeeds in MSVC10 and (but) results in a null pointer exception in c:\Program Files (x86)\Microsoft Visual Studio 10.0\VC\include\xutility line 123 _Iterator_base12& operator=(const _Iterator_base12& _Right) { // assign an iterator if (_Myproxy != _Right._Myproxy) _Adopt(_Right._Myproxy->_Mycont); return (*this); } _Right._Myproxy is NULL

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• Help needed with simple mysql group by query

  - by Jack

  This query fails when I add the line shown... :BEGIN FAIL: I have this so far Select Companyid, count(*) as cnt from mytable where State is not null and cnt = 1 <------------------------- FAIL group by CompanyID :END FAIL: Any way to do this? Here's a long winded background if it'll help.... I have a single table query. here's a sample of the table: CompanyID, State 1,OH 1,IL 1,NY 2,IL 3,NY 3,OH 4,NY 5,CA 5,WA I want a query that'll return something like this: 2,IL 4,NY I have this so far Select Companyid, count(*) as cnt from mytable where State is not null group by CompanyID This gives me a count of the number of records for each company. IE: 1,3 2,1 3,2 4,1 5,2 Now I want to filter the above list to just the two records with one result. I tried adding another where clause, but it failed: BEGIN FAIL: I have this so far Select Companyid, count(*) as cnt from mytable where State is not null and cnt = 1 <-------------------- FAIL group by CompanyID END FAIL:

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• Android list all images available

  - by Javadid

  hi friends, I m making an application which requires me to list all the images available on the SD-Card of the phone. i tried querying the ContentResolver way i.e. Cursor image = getContentResolver().query(Images.Media.EXTERNAL_CONTENT_URI, new String[]{Images.Media._ID,Images.Media.DATA,Images.Media.DISPLAY_NAME}, null, null, null); but without any result. Is there any way i can get the list or if thats not possible then is there any possible intent (e.g. PICK) by which i can allow the user to select a file and then access the path of the file the user selected?? Helppppp guys...

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• Force column order, Excel data table

  - by Chris

  I have a Excel Workbook that I use as a report template. I change the datasource on each pivot and datatable in a C# app. When I change the datatable datasource it tweeks the columns. Is there a way to force the column order? private void RefreshRawData(string dataSource, string connection) { xl._Worksheet ws = (xl._Worksheet)xlTemplate.Worksheets["Raw Data"]; xl.ListObject table = ws.ListObjects["Table_ExternalData_1"]; xl.QueryTable qt = table.QueryTable; qt.CommandText = dataSource; qt.Connection = GetExcelConnectionString((string)qt.Connection); qt.BackgroundQuery = false; qt.Refresh(m); Marshal.ReleaseComObject(ws); Marshal.ReleaseComObject(table); Marshal.ReleaseComObject(qt); ws = null; table = null; qt = null; }

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• Using Windows Vista Credentials

  - by Ehtsham

  Hi all i am using CredUIPromptForWinodwsCredentialw for prompting the user for verifying his/her credentials how can i verify these credentilas. the code i am using is BOOL save = false; DWORD authPackage = 0; LPVOID authBuffer; ULONG authBufferSize = 0; CREDUI_INFO credUiInfo; DWORD logininfo; credUiInfo.pszCaptionText = TEXT("My caption"); credUiInfo.pszMessageText = TEXT("My message"); credUiInfo.cbSize = sizeof(credUiInfo); credUiInfo.hbmBanner = NULL; credUiInfo.hwndParent = NULL; PCREDUI_INFO objpcredui; logininfo = CredUIPromptForWindowsCredentials(&(credUiInfo), 0, &(authPackage), NULL, 0, &authBuffer, &authBufferSize, &(save), 1|2);

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• problem while checking second check checkbox checked.

  - by kumar

  $('#nextpage').click(function() { $('#Details input[type=checkbox]').each( function() { if( $(this).attr('checked') ) { $("#tabs").tabs('enable', 3).tabs('select', 3); } else { $().ShowDialog('please select atleast one'); } }); }); <fieldset> <legend>information</legend> <input type="checkbox"> <label>ID#: <span><%=(null != a) ? Model.ID: 0%></span></label> <label>Name:<span><%=(null != a) ? Model.Name: null%></span></label> </fieldset> this filedset is for multiple users.. that is on the same page there are multiple fiedsetsfor multiple users.. how to handle those things.. thanks

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• StreamTokenizer Iterator Adapter help

  - by alpdog14

  I have this StreamTokenizer Iterator Adapter that is suppose to create a Tokenizer Iterator Index Builder then build the index from a STIA wrapped around a StreamTokenizer. I am having trouble implementing the hasNext and Next for my STIA, can anyone help me, here is my class: public class StreamTokenizerIteratorAdapter implements Iterator<Token> { DefaultIndexImpl index; StreamTokenizer source; public StreamTokenizerIteratorAdapter(final StreamTokenizer source) { if (source == null) throw new IllegalArgumentException("source == null"); } @Override public boolean hasNext() { return !index.isEmpty(); } public Token next() { if(!index.isEmpty()) return next(); else return null; } @Override public void remove() { throw new UnsupportedOperationException(); } } Should I be using the source element in the hasNext() and next()?

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• How to call a jquery function from an action method in controller?

  - by Hasan Fahim

  I have a requirement to open a popup from an action method in controller. The action method is basically registering a user. [HttpPost] public ActionResult Register(RegisterModel model) { if (ModelState.IsValid) { MembershipCreateStatus createStatus; Membership.CreateUser(model.UserName, model.Password, model.Email, null, null, true, null, out createStatus); if (createStatus == MembershipCreateStatus.Success) { FormsAuthentication.SetAuthCookie(model.UserName, false /* createPersistentCookie */); //------------------------------------------ //I need to call a jquery function from here //------------------------------------------ return RedirectToAction("Index", "Home"); } else { ModelState.AddModelError("", ErrorCodeToString(createStatus)); } } return View(model); } The jquery function, present in the view, would just make a hidden DIV, visible, and set the opacity, etc, to represent a popup. I need to call such a jquery function from the controller's action method shown above.

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• Cannot use scp on Mac OS X

  - by Robert

  Hi all, when I try to copy any file with scp on Mac OS X Snow Leopard from another machine I get this error: scp [email protected]:/home/me/file.zip . Password: ... ---> Couldn't open /dev/null: Permission denied this is the output of "ls -l /dev/null": crw-rw-rw- 1 root wheel 3, 2 May 14 14:10 /dev/null I am in the group wheel, and even if I do "sudo scp..." it doesn't work. It's driving me crazy, do you have any suggestion? Thanx!

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• How does cast in C#/.NET 3.5 work for types with '?'

  - by Inez

  This is my code which works public decimal? Get() { var res = ... return res.Count() > 0 ? res.First() : (decimal?) null; } and this one doesn't work public decimal? Get() { var res = ... return res.Count() > 0 ? res.First() : null; } giving the compiler error: Error 1 Type of conditional expression cannot be determined because there is no implicit conversion between 'decimal' and '<null>' I wonder why? any ideas?

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• problem-configure-jboss-to-work-with-jndi(3)

  - by Spiderman

  Sorry for opening new thread every time for the same problem. It's just that I'd like to refine my question during my investigation and it's hard to do it in stackoverflow structure on the same question (maybe on purpose). Anyway, in continuation to this thread http://stackoverflow.com/questions/2843218/problem-configure-jboss-to-work-with-jndi2 I discovered that when running an application that is deployed on my JBoss 4.2.3.GA, when I perform: Context initialContext = new InitialContext(); Object dataSource = initialContext.lookup("java:/DefaultDS"); I get null as a return value even though DefaultDS is the default datasource that comes with Jboss installation. and generally, how come initialContext return null value? if the datasource is not found it should throw NamingException and in other case it should return real object. What can I do with null? isn't it a bad error handling of javax.naming.InitialContext ???

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• How to Iterate a Resharper Template ?.

  - by sree

  I have a small Resharper Template I have written for Null check of a function Parameter (C#). Check.IsNotNull($param$, "$param$"); - Suggest Parameter - #1 I can now null check the function paramters one by one. But I want to be able to null check all the paramters at once through a template. Is it Possible in Resharper?. Is there someting like a "$Foreach" using which I can loop through parameter variables and write the code to check them one by one ?. (without writing out the foreach into the code) I see that the "Alt + Ins" does something similar. (Taking all Properties on the class and making them as parameters of a constructor). So hoping that there's a way out.

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• foreign key and index issue

  - by George2

  Hello everyone, I am using SQL Server 2008 Enterprise. I have a table and one of its column is referring to another column in another table (in the same database) as foreign key, here is the related SQL statement, in more details, column [AnotherID] in table [Foo] refers to another table [Goo]'s column [GID] as foreign key. [GID] is primary key and clustered index on table [Goo]. My question is, in this way, if I do not create index on [AnotherID] column on [Foo] explicitly, will there be an index created automatically for [AnotherID] column on [Foo] -- because its foreign key reference column [GID] on table [Goo] already has primary clustered key index? CREATE TABLE [dbo].[Foo]( [ID] [bigint] IDENTITY(1,1) NOT NULL, [AnotherID] [int] NULL, [InsertTime] [datetime] NULL CONSTRAINT DEFAULT (getdate()), CONSTRAINT [PK_Foo] PRIMARY KEY CLUSTERED ( [ID] ASC )WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY] ) ON [PRIMARY] ALTER TABLE [dbo].[Foo] WITH CHECK ADD CONSTRAINT [FK_Foo] FOREIGN KEY([Goo]) REFERENCES [dbo].[Goo] ([GID]) ALTER TABLE [dbo].[Foo] CHECK CONSTRAINT [FK_Foo] thanks in advance, George

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• Deep copying of tree view nodes.

  - by Kanags.Net

  I'm trying to copy a treeview nodes to treenodecollection for some other processing. When i execute the treeview.nodes.clear() in the next line, my treenodecollection is becoming null. Can you please tell me how to copy the treeview nodes to treenodecollection and keep the copies of the nodes even after calling Clear method of actual tree view nodes? TreeNodeCollection tnc = null; private TypeIn() { tnc = treeView1.Nodes; treeView1.Nodes.Clear(); //Now my tnc becomes null, but I want the tnc for future use. }

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• Finding mySQL duplicates, then merging data

  - by Michael Pasqualone

  I have a mySQL database with a tad under 2 million rows. The database is non-interactive, so efficiency isn't key. The (simplified) structure I have is: `id` int(11) NOT NULL auto_increment `category` varchar(64) NOT NULL `productListing` varchar(256) NOT NULL Now the problem I would like to solve is, I want to find duplicates on productListing field, merge the data on the category field into a single result - deleting the duplicates. So given the following data: +----+-----------+---------------------------+ | id | category | productListing | +----+-----------+---------------------------+ | 1 | Category1 | productGroup1 | | 2 | Category2 | productGroup1 | | 3 | Category3 | anotherGroup9 | +----+-----------+---------------------------+ What I want to end up is with: +----+----------------------+---------------------------+ | id | category | productListing | +----+----------------------+---------------------------+ | 1 | Category1,Category2 | productGroup1 | | 3 | Category3 | anotherGroup9 | +----+----------------------+---------------------------+ What's the most efficient way to do this either in pure mySQL query or php?

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• Binding sub report in Crystal report

  - by Aijaz Chauhan

  Is it compulsory to bind sub report if we put sub report in main report ? here is my problem : code snippet : DataTable dtExtraDoc = dtDocSub.Select("DocumentId=14").Length == 0 ? null : dtDocSub.Select("DocumentId=14").CopyToDataTable(); if (dtExtraDoc != null && dtExtraDoc.Rows.Count > 0) { if (dtExtraDoc.Rows[0]["ResponceId"].ToString() == "2") { repdoc.Subreports["subRpt-extra-Doc-textile-claim-query-letter.rpt"].SetDataSource(dtExtraDoc); } } If dtExtraDoc is null then it will not bind the sub report and hence it gives me error " Object reference not set to an instance of object" I am totally new to crystal reports please help me.. Thanks in advance.

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• C# Elegant way to handle checking for an item in a collection.

  - by JL

  I've posted a code sample below. Firstly let me explain termStore.Groups in the code below is a collection of Group Objects (The exact class is irrelevant). Checking for null : if (termStore.Groups[groupName] == null) seems like a logical (clean) approach, but if the Groups collection is empty then an exception is produced. using the termStore.Groups.Contains is not an option either because this expects a strong type i.e: .Contains(Group)... not .Contains(GroupName as string) Can someone recommend a clean / generic way I can check for if an item exists in collection . Thank you.... TermStore termStore = session.TermStores.Where(ts => ts.Name == termStoreName).FirstOrDefault(); if (termStore.Groups[groupName] == null) { termStore.CreateGroup(groupName); termStore.CommitAll(); } Update: The exact class Sharepoint Taxonomy Classes. http://msdn.microsoft.com/en-us/library/microsoft.sharepoint.taxonomy.group.aspx

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• reading csv file without for

  - by Abruzzo Forte e Gentile

  Hi All I need to read a CSV file in python. Since for last row I receive a 'NULL byte' error I would like to avoid using for keyword but the while. Do you know how to do that? reader = csv.reader( file ) for row in reader # I have an error at this line # do whatever with row I want to substitute the for-loop with a while-loop so that I can check if the row is NULL or not. What is the function for reading a single row in the CSV module? Thanks Thanks p.S. below the traceback Traceback (most recent call last): File "FetchNeuro_TodayTrades.py", line 189, in for row in reader: _csv.Error: line contains NULL byte

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• JPA atomic query/save for multithreaded app

  - by TofuBeer

  I am in the midst of changing my JPA code around to make use of threads. I have a separate entity manager and transaction for each thread. What I used to have (for the single threaded environment) was code like: // get object from the entity manager X x = getObjectX(jpaQuery); if(x == null) { x = new X(); x.setVariable(foo); entityManager.persist(x); } With that code in the multi threaded environment I am getting duplicate keys since, I assume, getObjectX returns null for a thread, then that thread is swapped out, the next thread calls getObjextX, also getting null, and then both threads will create and persist a new X(). Short of adding in synchronization, is there an atomic way to get/save-if-doesn't-exist a value with JPA or should I rethink my approach EDIT: I am using the latest Eclipselink and MySql 5.1

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