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Thread: Nick Novello

  1. #1
    Junior Member nnovello's Avatar
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    Angry Nick Novello

    /*****************************************************************************
    *     
    *      Authored by Nicolas Novello in Fall 2010
    *      File JSwift.java is an ultralight code editor-not quite IDE. 
    *      Yes I reinvented the wheel... and I hope you like it. Watch out EMACS...lol
    *
    *
    *      Notes:
    *          Problem now is I realized that I need to be able to control the programs that iv'e compiled and ran.
    *          I have to have a way to kill zombie processes w/o having to pull it up in a terminal window or task                                       *          manager. Also, stdOutput is not printed until the running process is dead.  In fact, a the JSwift
    *          window locks out completely.  Iv'e dealt with server-client relationships before and they suck.
    *          Is there any other way to start in a new process while keeping old one awake?  
    ******************************************************************************/
     
    	public void runApp (){
    		try {
     
    				int fileParentPathLength = Global.file.getParentFile().getPath().length();  //used to find program name w/o full path
    				systemCommand = ("java " + Global.file.getPath().substring(fileParentPathLength+1,Global.file.getPath().length()-5)); //will not work for .jar!! must change classpath somehow too!
    				Global.infoBox.append(systemCommand + "\n");
     
    				//I need to create separate threads from current by calling these commands:
    				Runtime rt = Runtime.getRuntime();
    				Process pr = rt.exec(systemCommand); 
    				//gives this command to the os to let it take care of business
     
    				//then I need to somehow look for any runtime errors, exceptions...			
    				Scanner errorScanner = new Scanner(pr.getErrorStream());
    				while (errorScanner.hasNext()) Global.infoBox.append((errorScanner.nextLine()) + "\n");
     
    				//and also test for what the command is reading back from the stdoutput. 
    				//I guess Id have to put them both in a loop waiting for the process to be killed. terrible.
    				Scanner inputScanner = new Scanner(pr.getInputStream());
    				while (inputScanner.hasNext())Global.infoBox.append((inputScanner.nextLine())+"\n");
    Last edited by nnovello; November 21st, 2010 at 08:06 PM.


  2. #2
    Super Moderator helloworld922's Avatar
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    Default Re: Nick Novello

    In the future, please use the edit button.

    What is the problem you're experiencing (if any)? If it's an exception, please post the exception message in full.

  3. #3
    Junior Member nnovello's Avatar
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    Default Re: Nick Novello

    Sorry not to to be clear. No exceptions, no compile errors. It runs. It just doesn't work the way I want it too. I guess im looking for implementation help really. If I open up a Test program inside of the Client, compile it and run it. It all works. However, once a new program is running, the JSwift client is put to sleep. StdOutput will not be displayed until after the program that is being run is closed.
    Last edited by nnovello; November 21st, 2010 at 08:09 PM.
    /***************************
    *
    * Nick Novello
    * University At Buffalo
    *
    ***************************/

  4. #4
    Super Moderator helloworld922's Avatar
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    Default Re: Nick Novello

    .... Both standard out println commands should be executed before the jframe is executed.

  5. #5
    Junior Member nnovello's Avatar
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    Default Re: Nick Novello

    Right.. That is if Test.java is run in a working code editor like emacs or vim or eclipse or notepad or whatever your norm. is. But inside the JSwift editor that I wrote, that is not what happens. This is because when using the compileApp() and runApp() methods, I start a new process to execute the commands javac and java on my Test.java file. This puts my JSwift editor to sleep! So if the code Test.java that your running gets stuck in a while(true) loop, it cannot be stopped! (unless you manually kill the process). Another side affect is the inability of the JSwift editor to display any standard output until the new process is ended. My question is what is the simplest way to get past this?
    /***************************
    *
    * Nick Novello
    * University At Buffalo
    *
    ***************************/

  6. #6
    Junior Member nnovello's Avatar
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    Default Re: Nick Novello

    So the standard output from Test.java is executed before the JFrame is closed, but is not appended to my Global.infoBox until after it is closed.
    /***************************
    *
    * Nick Novello
    * University At Buffalo
    *
    ***************************/

  7. #7
    Junior Member nnovello's Avatar
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    Default Re: Nick Novello

    So instead of doing this:
    Runtime rt = Runtime.getRuntime();
    Process pr = rt.exec(systemCommand);

    Do I need to implement Runnable and start these tasks as new threads in another class?
    /***************************
    *
    * Nick Novello
    * University At Buffalo
    *
    ***************************/

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