Search Results

Search found 21111 results on 845 pages for 'null pointer'.

Page 309/845 | < Previous Page | 305 306 307 308 309 310 311 312 313 314 315 316  | Next Page >

  • Best practice with respect to NPE and multiple expressions on single line

    - by JRL
    I'm wondering if it is an accepted practice or not to avoid multiple calls on the same line with respect to possible NPEs, and if so in what circumstances. For example: getThis().doThat(); vs Object o = getThis(); o.doThat(); The latter is more verbose, but if there is an NPE, you immediately know what is null. However, it also requires creating a name for the variable and more import statements. So my questions around this are: Is this problem something worth designing around? Is it better to go for the first or second possibility? Is the creation of a variable name something that would have an effect performance-wise? Is there a proposal to change the exception message to be able to determine what object is null in future versions of Java ?

    Read the article

  • How to load a configuration file at startup within tomcat

    - by Alex
    I want to be able to load my configuration for the webapp at startup of tomcat (apache commons configuration library) is this a possible way: public class MyAppCfg implements javax.servlet.ServletContextListener { private ServletContext context = null; @Override public void contextInitialized(ServletContextEvent event) { try{ this.context = event.getServletContext(); XMLConfiguration config = new XMLConfiguration("cfg.xml"); config.setReloadingStrategy(new FileChangedReloadingStrategy()); this.context.setAttribute("mycfg", config); } catch (Exception e) { e.printStackTrace(); } } @Override public void contextDestroyed(ServletContextEvent arg0) { this.context = null; } } web.xml <listener> <listener-class>mypackage.MyAppCfg</listener-class> </listener> and later acces them in the webapp via this.cfg = (XMLConfiguration) servletRequest.getAttribute("mycfg");

    Read the article

  • Dynamically set generic type argument

    - by fearofawhackplanet
    Following on from my question here, I'm trying to create a generic value equality comparer. I've never played with reflection before so not sure if I'm on the right track, but anyway I've got this idea so far: bool ContainSameValues<T>(T t1, T t2) { if (t1 is ValueType || t1 is string) { return t1.Equals(t2); } else { IEnumerable<PropertyInfo> properties = t1.GetType().GetProperties().Where(p => p.CanRead); foreach (var property in properties) { var p1 = property.GetValue(t1, null); var p2 = property.GetValue(t2, null); if( !ContainSameValues<p1.GetType()>(p1, p2) ) return false; } } return true; } This doesn't compile because I can't work out how to set the type of T in the recursive call. Is it possible to do this dynamically at all? There are a couple of related questions on here which I have read but I couldn't follow them enough to work out how they might apply in my situation.

    Read the article

  • C++ Linked List - Reading data from a file with a sentinel

    - by Nick
    So I've done quite a bit of research on this and can't get my output to work correctly. I need to read in data from a file and have it stored into a Linked List. The while loop used should stop once it hits the $$$$$ sentinel. Then I am to display the data (by searching by ID Number[user input]) I am not that far yet I just want to properly display the data and get it read in for right now. My problem is when it displays the data is isn't stopping at the $$$$$ (even if I do "inFile.peek() != EOF and omit the $$$$$) I am still getting an extra garbage record. I know it has something to do with my while loop and how I am creating a new Node but I can't get it to work any other way. Any help would be appreciated. students.txt Nick J Cooley 324123 60 70 80 90 Jay M Hill 412254 70 80 90 100 $$$$$ assign6.h file #pragma once #include <iostream> #include <string> using namespace std; class assign6 { public: assign6(); // constructor void displayStudents(); private: struct Node { string firstName; string midIni; string lastName; int idNum; int sco1; //Test score 1 int sco2; //Test score 2 int sco3; //Test score 3 int sco4; //Test score 4 Node *next; }; Node *head; Node *headPtr; }; assign6Imp.cpp // Implementation File #include "assign6.h" #include <fstream> #include <iostream> #include <string> using namespace std; assign6::assign6() //constructor { ifstream inFile; inFile.open("students.txt"); head = NULL; head = new Node; headPtr = head; while (inFile.peek() != EOF) //reading in from file and storing in linked list { inFile >> head->firstName >> head->midIni >> head->lastName; inFile >> head->idNum; inFile >> head->sco1; inFile >> head->sco2; inFile >> head->sco3; inFile >> head->sco4; if (inFile != "$$$$$") { head->next = NULL; head->next = new Node; head = head->next; } } head->next = NULL; inFile.close(); } void assign6::displayStudents() { int average = 0; for (Node *cur = headPtr; cur != NULL; cur = cur->next) { cout << cur->firstName << " " << cur->midIni << " " << cur->lastName << endl; cout << cur->idNum << endl; average = (cur->sco1 + cur->sco2 + cur->sco3 + cur->sco4)/4; cout << cur->sco1 << " " << cur->sco2 << " " << cur->sco3 << " " << cur->sco4 << " " << "average: " << average << endl; } }

    Read the article

  • Can not access android /data folder?

    - by fonter
    try { Runtime rt = Runtime.getRuntime(); Process pcs = rt.exec("ls -l /data"); BufferedReader br = new BufferedReader(new InputStreamReader(pcs .getInputStream())); String line = null; while ((line = br.readLine()) != null) { Log.e("line","line="+line); } br.close(); pcs.waitFor(); int ret = pcs.exitValue(); Log.e("ret","ret="+ret); } catch (Exception e) { Log.e("Exception", "Exception", e); } only print "ret=0",How to print the correct path?

    Read the article

  • Twitter Authentication through Android's AccountManager classes.

    - by Robby Pond
    I am working on a twitter based app and am trying to incorporate Android's built-in Account support for Twitter. The following code works to popup the confirmation dialog for my app to access twitter but I am unsure of what to pass in as the authenticationType. Any help would be appreciated. I've googled all over the place and can't seem to find the correct answer. It goes in place of "oauth" below. AccountManager am = AccountManager.get(this); Account[] accts = am.getAccountsByType(TWITTER_ACCOUNT_TYPE); if(accts.length > 0) { Account acct = accts[0]; am.getAuthToken(acct, "oauth"/*what goes here*/, null, this, new AccountManagerCallback<Bundle>() { @Override public void run(AccountManagerFuture<Bundle> arg0) { try { Bundle b = arg0.getResult(); Log.e("TrendDroid", "THIS AUTHTOKEN: " + b.getString(AccountManager.KEY_AUTHTOKEN)); } catch (Exception e) { Log.e("TrendDroid", "EXCEPTION@AUTHTOKEN"); } }}, null); }

    Read the article

  • How to remove duplicate line in a file

    - by Abs
    Hi I'm using the below method to write to a file from the Jtextarea and I call this method every 30 second within a Timer but instead to add only new line in file it rewrite the entire lines contained in Jtextarea so then I have duplicate lines. I want to avoid this and update the file just with new lines. Could you help me please. public void loger() { FileWriter writer = null; try { writer = new FileWriter("MBM_Log_"+date()+".txt" , true); textArea.write(writer); } catch (IOException exception) { System.err.println("log error"); exception.printStackTrace(); } finally { if (writer != null) { try { writer.close(); } catch (IOException exception) { System.err.println("Error closing writer"); exception.printStackTrace(); } } } }

    Read the article

  • How to handle Application_BeginRequest using a custom filter in asp.net mvc?

    - by denis_n
    How to handle Application_BeginRequest using a custom filter in asp.net mvc? I want to restore session only for one route (~/my-url). I would be cool, if I could create a custom filter and handle that. protected void Application_BeginRequest(object sender, EventArgs e) { var context = HttpContext.Current; if (string.Equals("~/my-url", context.Request.AppRelativeCurrentExecutionFilePath, StringComparison.OrdinalIgnoreCase)) { string sessionId = context.Request.Form["sessionId"]; if (sessionId != null) { HttpCookie cookie = context.Request.Cookies.Get("ASP.NET_SessionId"); if (cookie == null) { cookie = new HttpCookie("ASP.NET_SessionId"); } cookie.Value = sessionId; context.Request.Cookies.Set(cookie); } }

    Read the article

  • Deriving from a component and implementing IDisposable properly

    - by PaulH
    I have a Visual Studio 2008 C# .NET 2.0 CF project with an abstract class derived from Component. From that class, I derive several concrete classes (as in my example below). But, when I go to exit my Form, though the Form's Dispose() member is called and components.Dispose() is called, my components are never disposed. Can anybody suggest how I can fix this design? public abstract class SomeDisposableComponentBase : Component { private System.ComponentModel.IContainer components; protected SomeDisposableComponentBase() { Initializecomponent(); } protected SomeDisposableComponentBase(IContainer container) { container.Add(this); Initializecomponent(); } private void InitializeComponent() { components = new System.ComponentModel.Container(); } protected abstract void Foo(); #region IDisposable Members bool disposed_; /// Warning 60 CA1063 : Microsoft.Design : Ensure that 'SomeDisposableComponentBase.Dispose()' is declared as public and sealed.* public void Dispose() { // never called Dispose(true); GC.SuppressFinalize(this); } protected virtual void Dispose(bool disposing) { // never called if (!disposed_) { if (disposing && (components != null)) { components.Dispose(); } disposed_ = true; } base.Dispose(disposing); } #endregion } public SomeDisposableComponent : SomeDisposableComponentBase { public SomeDisposableComponent() : base() { } public SomeDisposableComponent(IContainer container) : base(container) { } protected override void Foo() { // Do something... } protected override void Dispose(bool disposing) { // never called base.Dispose(disposing); } } public partial class my_form : Form { private SomeDisposableComponentBase d_; public my_form() { InitializeComponent(); if (null == components) components = new System.ComponentModel.Container(); d_ = new SomeDisposableComponent(components); } /// exit button clicked private void Exit_Click(object sender, EventArgs e) { this.Close(); } /// from the my_form.designer.cs protected override void Dispose(bool disposing) { if (disposing && (components != null)) { // this function is executed as expected when the form is closed components.Dispose(); } base.Dispose(disposing); } } *I note that FX-Cop is giving me a hint here. But, if I try to declare that function as sealed, I get the error: error CS0238: 'SomeDisposableComponentBase.Dispose()' cannot be sealed because it is not an override Declaring that function an override leads to: 'SomeDisposableComponentBase.Dispose()': cannot override inherited member 'System.ComponentModel.Component.Dispose()' because it is not marked virtual, abstract, or override Thanks, PaulH

    Read the article

  • Query joining in sql server 2005

    - by Domnic
    I have two queries like: SELECT PC_COMP_CODE, PC_SL_LDGR_CODE, PC_SL_ACNO ACCOUNT, COUNT(PC_CHEQUE_NO) CHQS, SUM(CONVERT(FLOAT, PC_AMOUNT)) CHQ_AMT FROM GLAS_PDC_CHEQUES WHERE PC_COMP_CODE = '1' AND PC_DISCD IS NULL GROUP BY PC_SL_LDGR_CODE, PC_SL_ACNO ,PC_COMP_CODE ORDER BY PC_SL_ACNO -------------------------------------------------- SELECT COAD_PTY_FULL_NAME,PC_COMP_CODE, PC_SL_LDGR_CODE, PC_SL_ACNO, PC_DEPT_NO, PC_DOC_TYPE, PC_CHEQUE_NO, PC_BANK_AC_NO FROM GLAS_PTY_ADDRESS,GLAS_SBLGR_MASTERS,GLAS_PDC_CHEQUES WHERE COAD_COMP_CODE = '1' AND SLMA_COMP_CODE = COAD_COMP_CODE AND SLMA_ADDR_ID = COAD_ADDR_ID AND SLMA_LDGRCTL_CODE = PC_SL_LDGR_CODE AND PC_COMP_CODE=SLMA_COMP_CODE AND SLMA_ACNO = PC_SL_ACNO AND SLMA_LDGRCTL_YEAR = DBO.GLAS_VALIDATIONS_GET_OPEN_YEAR(PC_COMP_CODE) If I execute first query alone I get 5 records... If I join the above two query like: SELECT PC_COMP_CODE, PC_SL_LDGR_CODE, PC_SL_ACNO ACCOUNT, COUNT(PC_CHEQUE_NO) CHQS, SUM(CONVERT(FLOAT, PC_AMOUNT)) CHQ_AMT, COAD_PTY_FULL_NAME FROM GLAS_PDC_CHEQUES LEFT OUTER JOIN GLAS_SBLGR_MASTERS ON( SLMA_COMP_CODE=PC_COMP_CODE AND SLMA_LDGRCTL_CODE = PC_SL_LDGR_CODE AND SLMA_ACNO = PC_SL_ACNO ) LEFT OUTER JOIN GLAS_PTY_ADDRESS ON( SLMA_COMP_CODE = COAD_COMP_CODE AND SLMA_ADDR_ID = COAD_ADDR_ID) WHERE PC_COMP_CODE = '1' AND PC_DISCD IS NULL AND SLMA_LDGRCTL_YEAR = DBO.GLAS_VALIDATIONS_GET_OPEN_YEAR(PC_COMP_CODE) GROUP BY PC_SL_LDGR_CODE, PC_SL_ACNO ,PC_COMP_CODE,COAD_PTY_FULL_NAME ORDER BY PC_SL_ACNO then I just get 2 records.... I need that 5 records to display after join..... How can I do it?

    Read the article

  • Uploading file to DropBox causing UnlinkedException

    - by Boardy
    I am currently working on android project and trying to enable DropBox functionality. I've selected the access type to App Only, and I can successfully authenticate and it creates an Apps directory and inside that creates a directory with the name of my app. When I then try to put a file in the DropBox directory it goes into the DropBoxException catch and in the logcat prints com.dropbox.client2.exception.DropboxUnlinkedException. I've done a google and from what I've seen this happens if the apps directory has been deleted and so authentication is required to be re-done, but this isn't the case, I have deleted it and I am putting the file straight after doing the authentication. Below is the code that retrieves the keys and stores the file on dropbox. AccessTokenPair tokens = getTokens(); UploadFile uploadFile = new UploadFile(context, common, this, mDBApi); uploadFile.execute(mDBApi); Below is the code for the getTokens method (don't think this would help but you never know) private AccessTokenPair getTokens() { AccessTokenPair tokens; SharedPreferences prefs = context.getSharedPreferences("prefs", 0); String key = prefs.getString("dropbox_key", ""); String secret = prefs.getString("dropbox_secret", ""); tokens = new AccessTokenPair(key, secret); return tokens; } Below is the class that extends the AsyncTask to perform the upload class UploadFile extends AsyncTask<DropboxAPI<AndroidAuthSession>, Void, bool> { Context context; Common common; Synchronisation sync; DropboxAPI<AndroidAuthSession> mDBApi; public UploadFile(Context context, Common common, Synchronisation sync, DropboxAPI<AndroidAuthSession> mDBApi) { this.context = context; this.common = common; this.sync = sync; this.mDBApi = mDBApi; } @Override protected bool doInBackground(DropboxAPI<AndroidAuthSession>... params) { try { File file = new File(Environment.getExternalStorageDirectory() + "/BoardiesPasswordManager/dropbox_sync.xml"); FileInputStream inputStream = new FileInputStream(file); Entry newEntry = mDBApi.putFile("android_sync.xml", inputStream, file.length(), null, null); common.showToastMessage("Successfully uploade Rev: " + newEntry.rev, Toast.LENGTH_LONG); } catch (IOException ex) { Log.e("DropBoxError", ex.toString()); } catch (DropboxException e) { Log.e("DropBoxError", e.toString()); e.printStackTrace(); } return null; } I have no idea why it would display the UnlinkedException so any help would be greatly appreciated.

    Read the article

  • Programming style: should you return early if a guard condition is not satisfied?

    - by John Topley
    One thing I've sometimes wondered is which is the better style out of the two shown below (if any)? Is it better to return immediately if a guard condition hasn't been satisfied, or should you only do the other stuff if the guard condition is satisfied? For the sake of argument, please assume that the guard condition is a simple test that returns a boolean, such as checking to see if an element is in a collection, rather than something that might affect the control flow by throwing an exception. // Style 1 public SomeType aMethod() { SomeType result = null; if (!guardCondition()) { return result; } doStuffToResult(result); doMoreStuffToResult(result); return result; } // Style 2 public SomeType aMethod() { SomeType result = null; if (guardCondition()) { doStuffToResult(result); doMoreStuffToResult(result); } return result; }

    Read the article

  • Debugging stack data not assigned to a named variable

    - by gibbss
    Is there a way to view stack elements like un-assigned return values or exceptions that not assigned to a local variable? (e.g. throw new ...) For example, suppose I have code along the lines of: public String foo(InputStream in) throws IOException { NastyObj obj = null; try { obj = new NastyObj(in); return (obj.read()); } finally { if (obj != null) obj.close(); } } Is there any way to view the return or exception value without stepping to a higher level frame where it is assigned? This is particularly relevant with exceptions because you often have to step back up through a number of frames to find an actual handler. I usually use the Eclipse debugging environment, but any answer is appreciated. Also, if this cannot be done, can you explain why? (JVM, JPDA limitation?)

    Read the article

  • Why JPA injection not works on @PersistentUnit

    - by Dewfy
    Hello colleagues! It is continues of question ( http://stackoverflow.com/questions/2570976/struts-2-bean-is-not-created ) I'm using struts2 + toplink in my very simple web application under Tomcat. On the page I would like use iteration tag. That is why I've declared some factory (SomeFactory) that resolves collection of entities (Entity). Per article: http://download-uk.oracle.com/docs/cd/B32110_01/web.1013/b28221/usclient005.htm#CIHCEHHG the only thing I need is declaration: @PersistenceContext(unitName="name_in_persistence_xml") public class SomeFactory { @PersistenceUnit(unitName="name_in_persistence_xml") EntityManagerFactory emf; public EntityManager getEntityManager() { assert(emf != null); //HERE every time it is null return emf.createEntityManager(); } public Collection<Entity> getAll() { return getEntityManager().createNamedQuery("Entity.findAll").getResultList(); } } What is wrong? May be i miss something in web.xml? How to pre-init toplink for web application to allow injection happen?

    Read the article

  • empty() not a valid callback?

    - by user151841
    I'm trying to use empty() in array mapping in php. I'm getting errors that it's not a valid callback. $ cat test.php <? $arrays = array( 'arrEmpty' => array( '','','' ), ); foreach ( $arrays as $key => $array ) { echo $key . "\n"; echo array_reduce( $array, "empty" ); var_dump( array_map("empty", $array) ); echo "\n\n"; } $ php test.php arrEmpty Warning: array_reduce(): The second argument, 'empty', should be a valid callback in /var/www/authentication_class/test.php on line 12 Warning: array_map(): The first argument, 'empty', should be either NULL or a valid callback in /var/www/authentication_class/test.php on line 13 NULL Shouldn't this work? Long story: I'm trying to be (too?) clever and checking that all array values are not empty strings.

    Read the article

  • Elapsed time of running a C program

    - by yCalleecharan
    Hi, I would like to know what lines of C code to add to a program so that it tells me the total time that the program takes to run. I guess there should be counter initialization near the beginning of main and one after the main function ends. Is the right header clock.h? Thanks a lot... Update I have a Win Xp machine. Is it just adding clock() at the beginning and another clock() at the end of the program? Then I can estimate the time difference. Yes, you're right it's time.h. Here's my code: #include <stdio.h> #include <stdlib.h> #include <math.h> #include <share.h> #include <time.h> void f(long double fb[], long double fA, long double fB); int main() { clock_t start, end; start = clock(); const int ARRAY_SIZE = 11; long double* z = (long double*) malloc(sizeof (long double) * ARRAY_SIZE); int i; long double A, B; if (z == NULL) { printf("Out of memory\n"); exit(-1); } A = 0.5; B = 2; for (i = 0; i < ARRAY_SIZE; i++) { z[i] = 0; } z[1] = 5; f(z, A, B); for (i = 0; i < ARRAY_SIZE; i++) printf("z is %.16Le\n", z[i]); free(z); z = NULL; end = clock(); printf("Took %ld ticks\n", end-start); printf("Took %f seconds\n", (double)(end-start)/CLOCKS_PER_SEC); return 0; } void f(long double fb[], long double fA, long double fB) { fb[0] = fb[1]* fA; fb[1] = fb[1] - 1; return; } Some errors with MVS2008: testim.c(16) : error C2143: syntax error : missing ';' before 'const' testim.c(18) :error C2143: syntax error : missing ';' before 'type' testim.c(20) :error C2143: syntax error : missing ';' before 'type' testim.c(21) :error C2143: syntax error : missing ';' before 'type' testim.c(23) :error C2065: 'z' : undeclared identifier testim.c(23) :warning C4047: '==' : 'int' differs in levels of indirection from 'void *' testim.c(28) : error C2065: 'A' : undeclared identifier testim.c(28) : warning C4244: '=' : conversion from 'double' to 'int', possible loss of data and it goes to 28 errors. Note that I don't have any errors/warnings without your clock codes. LATEST NEWS: I unfortunately didn't get a good reply here. But after a search on Google, the code is working. Here it is: #include <stdio.h> #include <stdlib.h> #include <math.h> #include <share.h> #include <time.h> void f(long double fb[], long double fA, long double fB); int main() { clock_t start = clock(); const int ARRAY_SIZE = 11; long double* z = (long double*) malloc(sizeof (long double) * ARRAY_SIZE); int i; long double A, B; if (z == NULL) { printf("Out of memory\n"); exit(-1); } A = 0.5; B = 2; for (i = 0; i < ARRAY_SIZE; i++) { z[i] = 0; } z[1] = 5; f(z, A, B); for (i = 0; i < ARRAY_SIZE; i++) printf("z is %.16Le\n", z[i]); free(z); z = NULL; printf("Took %f seconds\n", ((double)clock()-start)/CLOCKS_PER_SEC); return 0; } void f(long double fb[], long double fA, long double fB) { fb[0] = fb[1]* fA; fb[1] = fb[1] - 1; return; } Cheers

    Read the article

  • How do I find the top N batters per year?

    - by Drew Stephens
    I'm playing around with the Lahman Baseball Database in a MySQL instance. I want to find the players who topped home runs (HR) for each year. The Batting table has the following (relevant parts) of its schema: +-----------+----------------------+------+-----+---------+-------+ | Field | Type | Null | Key | Default | Extra | +-----------+----------------------+------+-----+---------+-------+ | playerID | varchar(9) | NO | PRI | | | | yearID | smallint(4) unsigned | NO | PRI | 0 | | | HR | smallint(3) unsigned | YES | | NULL | | +-----------+----------------------+------+-----+---------+-------+ For each year, every player has an entry (between hundreds and 12k per year, going back to 1871). Getting the top N hitters for a single year is easy: SELECT playerID,yearID,HR FROM Batting WHERE yearID=2009 ORDER BY HR DESC LIMIT 3; +-----------+--------+------+ | playerID | yearID | HR | +-----------+--------+------+ | pujolal01 | 2009 | 47 | | fieldpr01 | 2009 | 46 | | howarry01 | 2009 | 45 | +-----------+--------+------+ But I'm interested in finding the top 3 from every year. I've found solutions like this, describing how to select the top from a category and I've tried to apply it to my problem, only to end up with a query that never returns: SELECT b.yearID, b.playerID, b.HR FROM Batting AS b LEFT JOIN Batting b2 ON (b.yearID=b2.yearID AND b.HR <= b2.HR) GROUP BY b.yearID HAVING COUNT(*) <= 3; Where have I gone wrong?

    Read the article

  • SQL GROUP BY with "default values"

    - by Christoph Schiessl
    I'm trying to create SELECT statement with a GROUP BY clause, which should return "default values". Imagine the following simple MySQL table: CREATE TABLE `tracker` ( `id` INTEGER PRIMARY KEY auto_increment, `date` DATETIME NOT NULL, `customer_id` INTEGER NOT NULL ); The table contains only one record: INSERT INTO `tracker` (`date`, `customer_id`) VALUES('2010-05-03', 1); After wards I'm executing the following SQL query: SELECT DATE(`date`), COUNT(customer_id) FROM tracker WHERE DATE(`date`) >= '2010-05-01' AND DATE(`date`) <= '2010-05-05' GROUP BY DATE(`date`) ORDER BY DATE(`date`); And get the expected result set: +----+---------------------+-------------+ | id | date | customer_id | +----+---------------------+-------------+ | 1 | 2010-05-10 00:00:00 | 1 | +----+---------------------+-------------+ However, I would like the result set to look like this: +--------------+--------------------+ | DATE(`date`) | COUNT(customer_id) | +--------------+--------------------+ | 2010-05-01 | 0 | | 2010-05-02 | 0 | | 2010-05-03 | 1 | | 2010-05-04 | 0 | | 2010-05-05 | 0 | +--------------+--------------------+ Is it possible to achieve this behavior?

    Read the article

  • what happens to running/blocked runnables when executorservice is shutdown()

    - by prmatta
    I posted a question about a thread pattern today, and almost everyone suggested that I look into the ExecutorService. While I was looking into the ExecutorService, I think I am missing something. What happens if the service has a running or blocked threads, and someone calls ExecutorService.shutdown(). What happens to threads that are running or blocked? Does the ExecutorService wait for those threads to complete before it terminates? The reason I ask this is because a long time ago when I used to dabble in Java, they deprecated Thread.stop(), and I remember the right way of stopping a thread was to use sempahores and extend Thread when necessary: public void run () { while (!this.exit) { try { block(); //do something } catch (InterruptedException ie) { } } } public void stop () { this.exit = true; if (this.thread != null) { this.thread.interrupt(); this.thread = null; } } How does ExecutorService handle running threads?

    Read the article

  • what does this code do?

    - by bstullkid
    It looks like this just sends a ping, but whats the point of that when you can just use ping? int main (int argc, char *argv[]) { unsigned int pid = 0; char buffer[2]; char *args[] = { "/bin/ping", "-c", "5", NULL, NULL }; if (argc != 2) return 0; args[3] = strdup(argv[1]); for (;;) { gets(buffer); /* FTW */ if (buffer[0] == 0x6e) break; switch (pid = fork()) { case -1: printf("Error Forking\n"); exit(255); case 0: execvp(args[0], args); exit(1); default: break; } } return 255; }

    Read the article

  • difference fixed width strings and zero-terminated strings

    - by robUK
    Hello, gcc 4.4.4 c89 I got into a recent discussion about "fixed width strings" and "zero terminated strings". When I think about this. They seem to be the same thing. A string with a terminating null. i.e. char *name = "Joe bloggs"; Is a fixed width string that cannot be changed. And also has a terminating null. Also in the discussion I was told that strncpy should never been used on 'zero terminated strings'. Many thanks for any susgestions,

    Read the article

  • Using "prevent execution of method" flags

    - by tpaksu
    First of all I want to point out my concern with some pseudocode (I think you'll understand better) Assume you have a global debug flag, or class variable named "debug", class a : var debug = FALSE and you use it to enable debug methods. There are two types of usage it as I know: first in a method : method a : if debug then call method b; method b : second in the method itself: method a : call method b; method b : if not debug exit And I want to know, is there any File IO or stack pointer wise difference between these two approaches. Which usage is better, safer and why?

    Read the article

  • MVC Bootstrap: Autocomplete doesn't show properly

    - by kicked11
    I have a MVC website and it had a searchbox with autocomplete, now I changed the layout using bootstrap. But now the autocomplete isn't been shown correctly anymore. See the picture the suggestions are not shown right. the autocomplete goes through the text. I was fine before I used bootstrap. I am using a SQL server to get the data and this is js file (I'm not good at ajax, i took it from a tutorial I followed) $(function () { var ajaxFormSubmit = function () { var $form = $(this); var options = { url: $form.attr("action"), type: $form.attr("method"), data: $form.serialize() }; $.ajax(options).done(function (data) { var $target = $($form.attr("data-aptitude-target")); var $newHtml = $(data); $target.replaceWith($newHtml); $newHtml.show("slide", 200); }); return false; }; var submitAutocompleteForm = function (event, ui) { var $input = $(this); $input.val(ui.item.label); var $form = $input.parents("form:first"); $form.submit(); }; var createAutocomplete = function () { var $input = $(this); var options = { source: $input.attr("data-aptitude-autocomplete"), select: submitAutocompleteForm }; $input.autocomplete(options); }; $("form[data-aptituder-ajax='true']").submit(ajaxFormSubmit); $("input[data-aptitude-autocomplete]").each(createAutocomplete); }); this is the form in my view <form method="get" action="@Url.Action("Index")" data-aptitude-ajax="true" data-aptitude-target="#testList"> <input type="search" name="searchTerm" data-aptitude-autocomplete="@Url.Action("Autocomplete")" /> <input type="submit" value=Search /> And this is part of the controller of the view public ActionResult Autocomplete(string term) { var model = db.tests .Where(r => term == null || r.name.Contains(term)) .Select(r => new { label = r.name }); return Json(model, JsonRequestBehavior.AllowGet); } // // GET: /Test/ public ActionResult Index(string searchTerm = null) { var model = db.tests .Where(r => searchTerm == null || r.name.StartsWith(searchTerm)); if (Request.IsAjaxRequest()) { return PartialView("_Test", model); } return View(model); } I'm new to ajax as well as bootstrap 3. I got the searchfunction and autocomplete from a tutorial I followed. Anybody any idea on how to fix this, because it worked fine? Thanks in advance!

    Read the article

  • forcing Management Studio to use alter table instead of drop/recreate

    - by marco
    Hi! I'm wondering if is there a way to force MSSQL Management Studio to produce a script like this: ALTER TABLE Mytable ADD MyCol bit NOT NULL CONSTRAINT MyColDefault DEFAULT 0 WITH VALUES ALTER TABLE [dbo].Mytable ALTER COLUMN MyCol2 int NULL GO when I alter a very simple property of a column on a table. If I do this in the designer and ask for the produced script, the script doesn't do such simple tasks, but instead copies all the data in a tmp table, drops the original table, renames the tmp table with the original table name. And, of course, drops and recreates every constraint and relationships. Is there any option I can change to change this behaviour? Or, this may be possible, is there some danger I don't see in using the simple ALTER TABLE above? thanks.

    Read the article

< Previous Page | 305 306 307 308 309 310 311 312 313 314 315 316  | Next Page >