Search Results

Search found 19541 results on 782 pages for 'event handling'.

Page 116/782 | < Previous Page | 112 113 114 115 116 117 118 119 120 121 122 123  | Next Page >

  • Handling file upload in a non-blocking manner

    - by Kaliyug Antagonist
    The background thread is here Just to make objective clear - the user will upload a large file and must be redirected immediately to another page for proceeding different operations. But the file being large, will take time to be read from the controller's InputStream. So I unwillingly decided to fork a new Thread to handle this I/O. The code is as follows : The controller servlet /** * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse * response) */ protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { // TODO Auto-generated method stub System.out.println("In Controller.doPost(...)"); TempModel tempModel = new TempModel(); tempModel.uploadSegYFile(request, response); System.out.println("Forwarding to Accepted.jsp"); /*try { Thread.sleep(1000 * 60); } catch (InterruptedException e) { // TODO Auto-generated catch block e.printStackTrace(); }*/ request.getRequestDispatcher("/jsp/Accepted.jsp").forward(request, response); } The model class package com.model; import java.io.IOException; import java.util.concurrent.ExecutionException; import java.util.concurrent.Future; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import com.utils.ProcessUtils; public class TempModel { public void uploadSegYFile(HttpServletRequest request, HttpServletResponse response) { // TODO Auto-generated method stub System.out.println("In TempModel.uploadSegYFile(...)"); /* * Trigger the upload/processing code in a thread, return immediately * and notify when the thread completes */ try { FileUploaderRunnable fileUploadRunnable = new FileUploaderRunnable( request.getInputStream()); /* * Future<FileUploaderRunnable> future = ProcessUtils.submitTask( * fileUploadRunnable, fileUploadRunnable); * * FileUploaderRunnable processed = future.get(); * * System.out.println("Is file uploaded : " + * processed.isFileUploaded()); */ Thread uploadThread = new Thread(fileUploadRunnable); uploadThread.start(); } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } /* * catch (InterruptedException e) { // TODO Auto-generated catch block * e.printStackTrace(); } catch (ExecutionException e) { // TODO * Auto-generated catch block e.printStackTrace(); } */ System.out.println("Returning from TempModel.uploadSegYFile(...)"); } } The Runnable package com.model; import java.io.File; import java.io.FileInputStream; import java.io.FileNotFoundException; import java.io.FileOutputStream; import java.io.IOException; import java.io.InputStream; import java.nio.ByteBuffer; import java.nio.channels.Channels; import java.nio.channels.ReadableByteChannel; public class FileUploaderRunnable implements Runnable { private boolean isFileUploaded = false; private InputStream inputStream = null; public FileUploaderRunnable(InputStream inputStream) { // TODO Auto-generated constructor stub this.inputStream = inputStream; } public void run() { // TODO Auto-generated method stub /* Read from InputStream. If success, set isFileUploaded = true */ System.out.println("Starting upload in a thread"); File outputFile = new File("D:/06c01_output.seg");/* * This will be changed * later */ FileOutputStream fos; ReadableByteChannel readable = Channels.newChannel(inputStream); ByteBuffer buffer = ByteBuffer.allocate(1000000); try { fos = new FileOutputStream(outputFile); while (readable.read(buffer) != -1) { fos.write(buffer.array()); buffer.clear(); } fos.flush(); fos.close(); readable.close(); } catch (FileNotFoundException e) { // TODO Auto-generated catch block e.printStackTrace(); } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } System.out.println("File upload thread completed"); } public boolean isFileUploaded() { return isFileUploaded; } } My queries/doubts : Spawning threads manually from the Servlet makes sense to me logically but scares me coding wise - the container isn't aware of these threads after all(I think so!) The current code is giving an Exception which is quite obvious - the stream is inaccessible as the doPost(...) method returns before the run() method completes : In Controller.doPost(...) In TempModel.uploadSegYFile(...) Returning from TempModel.uploadSegYFile(...) Forwarding to Accepted.jsp Starting upload in a thread Exception in thread "Thread-4" java.lang.NullPointerException at org.apache.coyote.http11.InternalInputBuffer.fill(InternalInputBuffer.java:512) at org.apache.coyote.http11.InternalInputBuffer.fill(InternalInputBuffer.java:497) at org.apache.coyote.http11.InternalInputBuffer$InputStreamInputBuffer.doRead(InternalInputBuffer.java:559) at org.apache.coyote.http11.AbstractInputBuffer.doRead(AbstractInputBuffer.java:324) at org.apache.coyote.Request.doRead(Request.java:422) at org.apache.catalina.connector.InputBuffer.realReadBytes(InputBuffer.java:287) at org.apache.tomcat.util.buf.ByteChunk.substract(ByteChunk.java:407) at org.apache.catalina.connector.InputBuffer.read(InputBuffer.java:310) at org.apache.catalina.connector.CoyoteInputStream.read(CoyoteInputStream.java:202) at java.nio.channels.Channels$ReadableByteChannelImpl.read(Unknown Source) at com.model.FileUploaderRunnable.run(FileUploaderRunnable.java:39) at java.lang.Thread.run(Unknown Source) Keeping in mind the point 1., does the use of Executor framework help me in anyway ? package com.utils; import java.util.concurrent.Future; import java.util.concurrent.ScheduledThreadPoolExecutor; public final class ProcessUtils { /* Ensure that no more than 2 uploads,processing req. are allowed */ private static final ScheduledThreadPoolExecutor threadPoolExec = new ScheduledThreadPoolExecutor( 2); public static <T> Future<T> submitTask(Runnable task, T result) { return threadPoolExec.submit(task, result); } } So how should I ensure that the user doesn't block and the stream remains accessible so that the (uploaded)file can be read from it?

    Read the article

  • [grails + xfire] How to handle errors in SOAP services?

    - by Mulone
    Hi all, I'm implementing a web service on the xfire plugin. I was wondering how I'm supposed to handle the errors. I tried with this setup but the error is not returned to the SOAP client: GaSession[] myMethod( String userId ) throws MyException{ GaUser user = GaUser.findByUserId( userId ) if (!user) throw new MyException("user ${userId} does not exist") // do stuff and return valid results } Is there a standard way to handle errors and return them to the client in a clear way? My log is full of messages like: 2010-06-13 18:20:40,926 [Thread-289] DEBUG aegis.XMLClassMetaInfoManager - Mapping file : /com/mycompany/MyClass.aegis.xml not found. Is there a way to fix this? Cheers!

    Read the article

  • @ExceptionHandler doesn't handle the thrown exceptions

    - by Javi
    Hello, I have a method in my controller which will handle the exceptions thrown by the application. So I have a method like this one. @Controller public class ExceptionController { @RequestMapping(value="/error") @ExceptionHandler(value={Exception.class, NullPointerException.class}) public String showError(Exception e, Model model){ return "tiles:error"; } } And to try I if it works I throw a NullPointerException in another method in other method controller: boolean a = true; if(a){ throw new NullPointerException(); } After the exception is thrown it is printed in the JSP, but it doesn't go throw my showError() method (I've set a breakpoint there and it never enters). showError() method will catch the exception and will show different error pages depending on the exception type (though now it always shows the same error page). If I go to the url /error it shows the error page so the showError() method is OK. I'm using Spring 3. What can be the problem? Thanks.

    Read the article

  • Properly handling NSURLConnection errors

    - by Cal S
    Hi, I have a simple form interface set up that send username and password information to a server: (working) NSString *postData = [NSString stringWithFormat:@"user=%@&pass=%@",[self urlEncodeValue:sysUsername],[self urlEncodeValue:password]]; NSLog(@"Post data -> %@", postData); /// NSData* postVariables = [postData dataUsingEncoding:NSASCIIStringEncoding allowLossyConversion:YES]; NSMutableURLRequest* request = [[[NSMutableURLRequest alloc] init] autorelease]; NSString* postLength = [NSString stringWithFormat:@"%d", [postVariables length]]; NSURL* postUrl = [NSURL URLWithString:@"http://localhost/~csmith/cocoa/test.php"]; [request setURL:postUrl]; [request setHTTPMethod:@"POST"]; [request setValue:postLength forHTTPHeaderField:@"Content-Length"]; [request setValue:@"application/x-www-form-urlencoded" forHTTPHeaderField:@"Content-Type"]; [request setHTTPBody: postVariables]; NSData *returnData = [NSURLConnection sendSynchronousRequest:request returningResponse:NULL error:NULL]; NSLog(@"Post data SENT & returned -> %@", returnData); How do I handle connection errors such as no internet connection, firewall, etc. Also, does this method use the system-wide proxy settings? Many of my users are behind a proxy. Thanks a lot!

    Read the article

  • Handling text menu in Python

    - by PulpFiction
    Hi all. I am trying to create a text based menu in Python. Here is the code: #!/usr/bin/env python def testcaseOutput(): print '1. Add. 2. Subtract. 3. Divide. 4. Multiply' try: answer = int(raw_input('Enter a value (1 - 4) >. ')) except ValueError: print 'Invalid input. Enter a value between 1 -4 .' testcaseOutput() if answer in range(1, 5): return answer else: print 'Invalid input. Enter a value between 1 - 4.' testcaseOutput() My question: When the user enters an invalid input, i.e. not a number, I want this function to get called again. So I used the recursive approach which I think is bad design. I use that approach again in the if answer in range(1, 5). Is there any other way to handle this? I need the prompt called again when there is an invalid input. Also, is there any way I can club the two constraints: check whether input is a number and check whether the number is in the range(1,5) together? As you can see, I am checking that individually.

    Read the article

  • Imageiio can't create imageinput stream

    - by pie154
    When using imageio.imageio.read iget a can't create ImageInput Stream. I have a catch exception around it so the program survives but i was wondering if theres a way to put an if statement round it that checks to see if it falied and then attempt to read it again if it did. basically asking if there is a test for exceptions?

    Read the article

  • Would I want to throw an exception or an error in this PHP script?

    - by Tower
    Hi, I have a PHP script that runs database queries. Now, if a query fails, should I trigger an error or throw an exception? I noticed that if I do the latter, the script execution will stop after facing the exception. My code is as follows: if (!$this->connection[0]->query($this->query)) throw new Exception($this->connection[0]->error); What are the pros and cons of using exceptions for this kind of cases (failed queries)?

    Read the article

  • Porting Windows C++ to Standard (Linux) C++ - WSAGetLastError()

    - by Donal Rafferty
    I am currently porting some Windows mobile C++ code to standard C++. So I am trying to find alternatives for windows specific functions. I have had very little luck in finding a standard C++ function that can help me replace the WSAGetLastError() windows specific function. WSAGetLastError() returns error numbers for errors that occur with sockets in windows. So I was wondering if anyone was aware of a way to replace this function in standard c++? A way to get different error numbers for different outcomes of connecting/dissconection a socket would be sufficent.

    Read the article

  • Why can I check some event handlers for null, some not?

    - by Inno
    Hi, I have a ugly piece of code that adds event handlers. The problem is, if the code is called multiple times, the event handlers are called multiple times. To solve the problem, I remove the event handler first and then add it. Now I've seen the following behaviour: Some event handlers can be checked like: if (object.event == null) { // // Code // } others of the form if (object.object.event == null) { // // Code // } I get a message like 'object.object.event' may only occur left of -= or +=. (Since I'm using a german version of visual studio, I don't know the correct translation to english). I have no idea why the behaviour looks this inconsequent so I would be grateful for some information on this. To be more specific: It's user control. if (myControl.Event == null) { // // works // } if (myControl.TreeView.NodeMouseClick == null) { // // doesn't work // }

    Read the article

  • Handling missing data

    - by soppotare
    Say I have a simple helpdesk application which logs calls made by users. I would typically have such fields in a table relating to the call e.g. CallID, Description, CustomerID etc. I Would also have a table of customers including CustomerID, Username, Password, FullName etc. Now when a user is deleted from the customers table then the inner join between the calls table and the users table to find out historically which user logged a call would produce no results. How do people usually deal with this? Have seperate customer and useraccount tables Just disable the accounts so the data is still available Record the customers name in the calls table as a seperate field. or any other methods / suggestions?

    Read the article

  • PHP turn off errors - in one file only

    - by Industrial
    Hi! I am well aware about error_reporting(0); & ini_set('display_errors', "Off"); to make error messages go away. What would be an appropriate way to do this - for a specific file or part of code only? Surpressing errors with @'s seems like a bad idea since it apparently slows the code down... Thanks!

    Read the article

  • sql exception handling

    - by christine33990
    CREATE OR REPLACE PROCEDURE p_createLocaltable IS table_already_exist EXCEPTION; PRAGMA EXCEPTION_INIT (table_already_exist, -00955); BEGIN create table local_table as select * from supplied_table where rownum < 1; EXCEPTION when table_already_exist then DBMS_OUTPUT.put_line('Table already exists , does not need to recreate it'); END; can anyone see any problem of the above code?

    Read the article

  • Handling "other" option in dropdown select with free text input field

    - by ted776
    Hi, I'm trying to figure out the best way to handle a dropdown list where one of the options "other" shows a hidden text field (via jQuery), where the user can then enter text. Should both the dropdown and the input field be given the same "name" attribute, then server side code runs a check on the values of each in order to know what one is the active value - e.g if the value of the select box is "other", then check the value of the text input field - if this isn't the default value ("enter text"), then it's ok to use this value and save it to the database. Is this a messy approach to this problem?

    Read the article

  • What's the best practice in case something goes wrong in Perl code?

    - by Geo
    I saw code which works like this: do_something($param) || warn "something went wrong\n"; and I also saw code like this: eval { do_something_else($param); }; if($@) { warn "something went wrong\n"; } Should I use eval/die in all my subroutines? Should I write all my code based on stuff returned from subroutines? Isn't eval'ing the code ( over and over ) gonna slow me down?

    Read the article

  • Handling Model Inheritance in ASP.NET MVC2

    - by enth
    I've gotten myself stuck on how to handle inheritance in my model when it comes to my controllers/views. Basic Model: public class Procedure : Entity { public Procedure() { } public int Id { get; set; } public DateTime ProcedureDate { get; set; } public ProcedureType Type { get; set; } } public ProcedureA : Procedure { public double VariableA { get; set; } public int VariableB { get; set; } public int Total { get; set; } } public ProcedureB : Procedure { public int Score { get; set; } } etc... many of different procedures eventually. So, I do things like list all the procedures: public class ProcedureController : Controller { public virtual ActionResult List() { IEnumerable<Procedure> procedures = _repository.GetAll(); return View(procedures); } } but now I'm kinda stuck. Basically, from the list page, I need to link to pages where the specific subclass details can be viewed/edited and I'm not sure what the best strategy is. I thought I could add an action on the ProcedureController that would conjure up the right subclass by dynamically figuring out what repository to use and loading the subclass to pass to the view. I had to store the class in the ProcedureType object. I had to create/implement a non-generic IRepository since I can't dynamically cast to a generic one. public virtual ActionResult Details(int procedureID) { Procedure procedure = _repository.GetById(procedureID, false); string className = procedure.Type.Class; Type type = Type.GetType(className, true); Type repositoryType = typeof (IRepository<>).MakeGenericType(type); var repository = (IRepository)DependencyRegistrar.Resolve(repositoryType); Entity procedure = repository.GetById(procedureID, false); return View(procedure); } I haven't even started sorting out how the view is going to determine which partial to load to display the subclass details. I'm wondering if this is a good approach? This makes determining the URL easy. It makes reusing the Procedure display code easy. Another approach is specific controllers for each subclass. It simplifies the controller code, but also means many simple controllers for the many procedure subclasses. Can work out the shared Procedure details with a partial view. How to get to construct the URL to get to the controller/action in the first place? Time to not think about it. Hopefully someone can show me the light. Thanks in advance.

    Read the article

  • Creating interruptible process in python

    - by Glycerine
    I'm creating a python script of which parses a large (but simple) CSV. It'll take some time to process. I would like the ability to interrupt the parsing of the CSV so I can continue at a later stage. Currently I have this - of which lives in a larger class: (unfinished) Edit: I have some changed code. But the system will parse over 3 million rows. def parseData(self) reader = csv.reader(open(self.file)) for id, title, disc in reader: print "%-5s %-50s %s" % (id, title, disc) l = LegacyData() l.old_id = int(id) l.name = title l.disc_number = disc l.parsed = False l.save() This is the old code. def parseData(self): #first line start fields = self.data.next() for row in self.data: items = zip(fields, row) item = {} for (name, value) in items: item[name] = value.strip() self.save(item) Thanks guys.

    Read the article

  • Handling dynamic number of columns

    - by Whistle
    I'm developing a CMS of sorts, and I want to give my users the possibility of customizing the display. More precisely, I want to give them the ability to choose to display or hide the left column, the right column and/or the top div. The middle column cannot be hidden since this is where the actual content will show, whereas the other columns are for navigation or side menus. I've been looking for a way to make this as smart and flexible as possible. For now I'm using a MasterPage, but that seems to be too constraining. For instance, with MasterPage you need to add a ContentPlaceHolder control in every of your ASPX pages. What are the best practices in this area? I guess a simpler way of saying this would be "I want to create a template system over which I have complete control".

    Read the article

  • Proper mechanism for sending PHP errors to the client

    - by Chris
    Greetings, I was trying to discover a proper way to send captured errors or business logic exceptions to the client in an Ajax-PHP system. In my case, the browser needs to react differently depending on whether a request was successful or not. However in all the examples I've found, only a simple string is reported back to the browser in both cases. Eg: if (something worked) echo "Success!"; else echo "ERROR: that failed"; So when the browser gets back the Ajax response, the only way to know if an error occurred would be to parse the string (looking for 'error' perhaps). This seems clunky. Is there a better/proper way to send back the Ajax response & notify the browser of an error? Thank you.

    Read the article

  • Javascript, problem with binding an event to a div-tag

    - by Patrick
    Hello, i am trying to bind an event to a dynamically created div. function GameField(playerNumber) { this.fields = new Array(); this.player = playerNumber; this.isPlayerActive = false; this.currentRound = 0; } GameField.prototype.InitField = function(fieldNumber) { var newField = document.createElement("div"); if (fieldNumber == 0 || fieldNumber == 6 || fieldNumber == 8 || fieldNumber == 17) newField.className = 'gameCellSmall borderFull gameText gameTextAlign'; else newField.className = 'gameCellSmall borderWithoutTop gameText gameTextAlign'; newField.onclick = function() { this.DivClick('a'); } this.fields[fieldNumber] = newField; return newField; } GameField.prototype.DivClick = function(fieldNumber) { alert('Nummer: ' + fieldNumber); } Everything works perfectly, but when you click on one of the created divs, i end up with the following error message: Error: Object doesn't support this property or method. If i replace the onclick function with this, then it works: newField.onclick = function() { alert('Nummer: ' + fieldNumber); } How can i get the onclick event to fire my DivClick function instead?

    Read the article

  • Handling null values with PowerShell dates

    - by Tim Ferrill
    I'm working on a module to pull data from Oracle into a PowerShell data table, so I can automate some analysis and perform various actions based on the results. Everything seems to be working, and I'm casting columns into specific types based on the column type in Oracle. The problem I'm having has to do with null dates. I can't seem to find a good way to capture that a date column in Oracle has a null value. Is there any way to cast a [datetime] as null or empty?

    Read the article

< Previous Page | 112 113 114 115 116 117 118 119 120 121 122 123  | Next Page >