Refreshing Screen while Multi-Threading

I am trying to refresh a GUI while calling a class that extends the Thread class.My code looks similiar to this:
myThreadingClass mtc=new myThreadingClass();
mtc.start();
while(mtc.isAlive()){
repaint();
invalidate():
The isAlive() is never returning false! ? ! I somehow need to do the repaint while waiting for the thread to finish. I had a mtc.join() before that worked and went on in the program, but I did not have any way to refresh the GUI with the mtc.join().
Any one have any good ideas?

I need to keep refreshing the screen, and from what I understand invokeLater(Runnable r) will invoke the run() after other processes have finished, by not while the run() is in progress. You can tell me if I am correct, or if the GUI thread will automatically repaint while the run() is in progress? I would greatly appriciate this. I can't find helpful information on this topic!

Similar Messages

Helpful hint while multi-threading

Hi all
This had me stupmed for a little while. A multi-threaded program I'd been working didn't appear to be working correctly. I noticed this was because it looked like the thread never made it to its run() method. The cause of this was the fact id overridden the start() method of the thread without including this.run() at the end. The symptoms of this happening aren't obvious though, and it can be quite puzzling. I hope this gets added to any FAQs etc, or solves someones problem.

And if, for whatever reason, you do need to override start(), you should not call this.run() at the end, you should call super.start() !!!
If you call this.run() at the end, you are having the current thread go and do the run method.

Refreshing Screen While Observing

When I am viewing multiple machines. One of the machines being observed is not refreshing. Has anyone else had this problem?
Does anyone know how to fix it. All the other machines show accurate screens.
Just this one machine shows a screen that is not accurate. If I resize it refreshes and is correct but just for a few seconds.
I wasn't sure if anyone else is having the same problem.
thanks

I have exactly the same problem. It is not Remote Apple Events (I never turned on this feature). It is a Problem of the Client in conjunction with Version 3 of the Admin. Because: I get this problem with 2.2 Client too. My main machine in the office is still running MOSX 10.3.9 with ARD 2.2. It NEVER had this problem before, only since I control it with ARD 3 from my MacBook Pro.
I discover the Problem arise after controlling a remote server for 3 to 8 minutes. Then suddenly screen refreshing stops. First I always closed the window to the remote system and reopened it, clicked blindly one command (or some more via keyboard) then closed and reopened the window to see, if my commands have been done… TEDIOUS!
I realized that a restart of the ARD Client machine resolves the problem. But this is no solution, as I'm administering servers that are used!
I also realized that after being disconnected about an hour or so, the problem is gone and I'm able to control the remote system for another 5 minutes or so.
ssh to the remote system and restart ARD seems a good solution. BTW those folks reinstalling the Client: this also restarts it…
A nicer way is to send the CLI command (/System/Library/CoreServices/RemoteManagement/ARDAgent.app/Contents/Resources/ kickstart -restart -agent) via ARD! You can save this command…
But hey Apple, please fix this problem ASAP!

Program Crashes while multi-threading

Hi Gurus:
I am working on a program where I am running multiple JInternalFrames inside a JFrame. Each JInternalFrame starts a new thread (when the OK button is pressed). The thread calls a native (C++) method, which interfaces with another API (CAD).
Problem is that when I run two frames together, my program crashes. If I wait for one frame to complete the process and then start the second one, everything works fine. I am not sharing any data between the threads. I even put a synchronized access modifier in front of the method that is causing the crash, to no avail. Don't know what else to try. I also ran the program in two different processes with only invoking one frame in each process, and it worked fine.
The program either crashes with no error message, or sometimes it gives this error:
-------------- Start of error --------------------------
Another exception has been detected while we were handling last error.
Dumping information about last error:
ERROR REPORT FILE = (N/A)
PC = 0x22ABDFFD
SIGNAL = -1073741819
FUNCTION NAME = (N/A)
LIBRARY NAME = (N/A)
Please check ERROR REPORT FILE for further information, if there is any.
Good bye.
----------- End of error -------------------------------
Any help would be appreciated.
Regards,
Kamran

I also got that error - sometimes.
Now I get something like this :
An unexpected exception has been detected in native code outside the VM.
Unexpected Signal : 11 occurred at PC=0x403bce8e
Function name=__libc_free
Library=/lib/libc.so.6
Dynamic libraries:
08048000-0804c000 r-xp 00000000 08:01 17180 /usr/java/jdk1.3.1_01/bin/i386/native_threads/java
0804c000-0804d000 rw-p 00003000 08:01 17180 /usr/java/jdk1.3.1_01/bin/i386/native_threads/java
40000000-40016000 r-xp 00000000 08:01 446282 /lib/ld-2.2.2.so
40016000-40017000 rw-p 00015000 08:01 446282 /lib/ld-2.2.2.so
and so on.
I got an application which starts 50 threads (sometimes I start 60 or 30, just testing right now).
Do you've got RedHat? And Kernel 2.4.2-2smp?
I don't know how I got rid of your error, but now I got that one...
Anybody who has experiences with that?
THX,
Peter

Analysis for Office support multi thread?

Does Analysis for Office support multi thread/core? If so, what verison? I tried searching around this site as well as note 1466118 - Hardware & Software requirements for Analysis, edition for MS Office but was unable to find an answer.
I am on an Intel dual cpu with hyper threading turned on so it essentially looks like 4 cores. When I execute an Analysis View, I rarely see the EXCEL.EXE process go above 25% CPU utilization. I have plenty of RAM and hard drive space.
64bit Windows 7
32bit Office 2010
AAO 1.3.5.2288
Thanks

I found the following info at:
Excel 2010 Performance: Performance and Limit Improvements
Large Data Sets and 64-bit Excel
The 64-bit version of Excel 2010 is not constrained to 2 GB of RAM like 32-bit applications. Therefore, 64-bit Excel 2010 enables users to create much larger workbooks. 64-bit Windows enables a larger addressable memory capacity, and 64-bit Excel is designed to take advantage of that capacity. For example, users are able to fill more of the grid with data than was possible in previous versions of Excel. As more RAM is added to the computer, Excel uses that additional memory, allows larger and larger workbooks, and scales with the amount of RAM available.
In addition, because 64-bit Excel enables larger data sets, both 32-bit and 64-bit Excel 2010 introduce improvements to common large data set tasks such as entering and filling down data, sorting, filtering, and copying and pasting data. Memory usage is also optimized to be more efficient, in both the 32-bit and 64-bit versions of Excel.
Multi-Core Processing
Additional investments were made to take advantage of multi-core processors and increase performance for routine tasks. Starting in Excel 2010, the following features use multi-core processors: saving a file, opening a file, refreshing a PivotTable (for external data sources, except OLAP and SharePoint), sorting a cell table, sorting a PivotTable, and auto-sizing a column.
For operations that involve reading and loading or writing data, such as opening a file, saving a file or refreshing data, splitting the operation into two processes increases performance speed. The first process gets the data, and the second process loads the data into the appropriate structure in memory or writes the data to a file. In this way, as soon as the first process beings reading a portion of data, the second process can immediately start loading or writing that data, while the first process continues to read the next portion of data. Previously, the first process had to finish reading all the data in a certain section before the second process could load that section of the data into memory or write the data to a file.

Refreshing GUI while MultiThreading

I am trying to refresh a GUI while calling a class that extends the Thread class.My code looks similiar to this:
myThreadingClass mtc=new myThreadingClass();
mtc.start();
while(mtc.isAlive()){
repaint();
invalidate():
The isAlive() is never returning false! ? ! I somehow need to do the repaint while waiting for the thread to finish. I had a mtc.join() before that worked and went on in the program, but I did not have any way to refresh the GUI with the mtc.join().
Any one have any good ideas?

If mtc.isAlive() is always returning true then obviously it hasn't exitted myThreadingClass.run() yet.
So you need to look at what causes run() to exit there.
Also you needto make thread safe calls to Swing by using the SwingUtilities class. Trying to update a Swing component from another thread is inherently unsafe because Swing is non-reentrant.
- Also : You can repaint then invalidate().... should swap that around.
- Also : You're refreshing the screen in a while loop without any delays.
Try putting in a sleep() for a little bit.
regards,
Owen
while ( mtc.isAlive() )
     // IMPORTANT : You can't update a Swing component in another
     // Thread. You must update it in a "Swing friendly" manner.
     // Hence this helper function.
     try
          Thread.sleep ( 1000 );     // refresh screen once a second... can be changed
     catch (InterruptedException ignore )
     final Runnable runnable = new Runnable()
         public void run()
              invalidate();
              repaint();
         } // run
     };    // runnable
     SwingUtilities.invokeLater(runnable);
}

How to use Multi Thread to make a animation

Hello
Currently i am writing a router simulator using Java SE 1.4.2. I am facing a problem that is I cannot use multithread to update my Jframe animation.
Here i give my approach.
My idea is I used a JPanel in JFrame and I used Graphics g draw all background in Jpanel and add it into Jframe. It works since there is no animation invovled. I want to do some animation based on this background which i draw. But all animation should be controled by other threads due to i want other threads can control all animation. But i hit a error which is nullpointexception. The reason looks like which i used another to do animation, it cannot find the reference which is point to the Jpanel and Jframe. May u teach me a correct way to do multi threads animation in Jframe? thanks.
all the best and regards!

A simple annimation moving a circle round a screen. This uses a model that defines the dynamics of the annimation, a view to display a visual representation of the model and an event system (observer/observable) to notify the view that the model has changed.
I hope this helps.
import java.awt.*;
import javax.swing.*;
import java.util.*;
public class Test20041023 extends JFrame
    public Test20041023()
        super("Simple Annimation Demo");
        AnnimationModel annimationModel = new AnnimationModel();
        AnimationView animationView = new AnimationView(annimationModel);
        setContentPane(animationView);
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        pack();
    private static class AnimationView extends JPanel
        private static final int PREFERRED_WIDTH = 512;
        private static final int PREFERRED_HEIGHT = 256;
        AnimationView(AnnimationModel annimationModel)
            // Save a reference to the model for use
            // when the view is updated
            annimationModel_ = annimationModel;
            // Listen for the events indicating that the model has changed
            annimationModel_.addObserver(new Observer()
                public void update(Observable o, Object arg)
                    // All we need to do is to get the view to repaint
                    AnimationView.this.repaint();
        public void paintComponent(Graphics g)
            super.paintComponent(g);
            // Update the view based on the information in the model.
            g.setColor(Color.red);
            // Convert the model positions to view positions
            // in this case by scaling to the actual width and height.
            int xScreenPosition = scaleValue(annimationModel_.getX(), getWidth() - 20 ) + 5;
            int yScreenPosition = scaleValue(annimationModel_.getY(), getHeight() - 20 ) + 5;
            // Display the position of the point
            g.fillOval(xScreenPosition, yScreenPosition, 10, 10);
        private int scaleValue(double v, double size)
            return (int)((v+1.0)*0.5 * size + 0.5);
        public Dimension getPreferredSize()
            return new Dimension(PREFERRED_WIDTH, PREFERRED_HEIGHT);
        // The saved reference to the model
        private AnnimationModel annimationModel_;
    private static class AnnimationModel extends Observable
        AnnimationModel()
            Thread annimationThread = new Thread()
                public void run()
                    // Loop forever updating the model
                    // and notifying the observers.
                    while(true)
                        // Wait 0.05 seconds until the next frame update point
                        try
                            sleep(50L);
                        catch (InterruptedException e)
                            // Nothing to do
                        // Update the model - in this case it is very simple
                        theta_ += 0.1;
                        // Notify the observers
                        setChanged();
                        notifyObservers();
            annimationThread.start();
        // Model access methods
        public double getX()
            return Math.cos(theta_);
        public double getY()
            return Math.sin(theta_);
        // The angular position of the point
        private double theta_;
    // Simple test main
    static public void main(String[] args)
        new Test20041023().setVisible(true);
}

Can Acrobat 9 Multi-Thread (use all my cpu cores)

i have several 700+ page thick PDF documents i want to run OCR on. i can batch run them just fine, however i cannot get adobe to use more than one core of my 8 core iMac. so the process takes needlessly long because 87% of my CPU power is just sitting idle. i also cannot do anything with adobe while it is running its OCR program.
is there a way to force acrobat to be multi-threaded?
is there a way to use it for other things while its working?

Nope, no version of Acrobat is a multithreaded application. See the first bullet point: http://livedocs.adobe.com/acrobat_sdk/9.1/Acrobat9_1_HTMLHelp/DevFAQ_Introduction.21.16.ht ml

Multi-thread failure - Error in assignment

Hello
I have a c++ program processor running under Windows XP with Oracle 9i. My program access to oracle by an ODBC driver version 9.2.0.4.0. It could be launched in multi-thread to increase performance. When I launch it with one thread everything is fine. When I use several threads I have problems. ODBC driver returns to me a "error in assignment ... General error" message and my updates queries failed. Under SQl server it works without problems. It seems to be a kind of deadlock. When I disable check box in my odbc driver of "enable query timeout" my program encounter a problem and freezes...
Could someone help me ?

user13335017 wrote:
I have thought of the above solutions as workable, however, it is not. Some exhibited errors are:
A. "Attempt to use database while environment is closed." This error applies to 2, 3 and 4 all the way;
B. "Attempt to read / write database while database is closed." This error applies to 3 in particular;
C. "Attempt to close environment while some database is still open." This error applies to 5.
Please help me with designing a better strategy to solve the concurrent issue. Many thanks in advance.All these are expected errors. You should design the application so that you do not close an environment handle while database handles are still open, keep database handles open for as long as operations need to be performed on the underlying databases, open the database handles after opening the database handles, and close database handles before closing the environment handle.
In short, in pseudo-code, you should have something like this:
- open environment handle,
- open database handles,
- perform whatever operations are needed on the databases,
- close database handles,
- close environment handle.
You can refer to the Getting Started with Data Storage and the Getting Started with Transaction Processing guides appropriate for the API you are using, from the Berkeley DB documentation page.
Regards,
Andrei

Oracle 8 on Linux in Multi-Thread mode

I installed Oracle 8.0.5.0.0 on Linux RedHat 5.1
But I cann't startup database in multi-threaed mode.
When I try to startup DB the errors follow
SVRMGR> startup;
ORA-00101: invalid specification for system parameter
MTS_DISPATCHERS
ORA-00102: network protocol
(ADDRESS=(PARTIAL=YES)(PROTOCOL=tcp)) cannot be used by
dispatchers
My configuration files are:
listener.ora
LISTENER =
(ADDRESS_LIST =
(ADDRESS= (PROTOCOL= IPC)(KEY= orcl))
(ADDRESS= (PROTOCOL= IPC)(KEY= PNPKEY))
(ADDRESS= (PROTOCOL= TCP)(Host=
pcstar.kharkov.ua)(Port= 1521))
SID_LIST_LISTENER =
(SID_LIST =
(SID_DESC =
(GLOBAL_DBNAME= pcstar.kharkov.ua)
(ORACLE_HOME= /usr/oracle)
(SID_NAME = orcl)
(SID_DESC =
(SID_NAME = extproc)
(ORACLE_HOME = /usr/oracle)
(PROGRAM = extproc)
STARTUP_WAIT_TIME_LISTENER = 0
CONNECT_TIMEOUT_LISTENER = 10
TRACE_LEVEL_LISTENER = OFF
tnslistener working normally
tnsnames.ora
extproc_connection_data =
(DESCRIPTION =
(ADDRESS = (PROTOCOL = IPC)(KEY = orcl))
(CONNECT_DATA = (SID = extproc))
orcl =
(DESCRIPTION =
(ADDRESS = (PROTOCOL= TCP)(Host=
pcstar.pcstar.kharkov.ua)(Port= 1521))
(CONNECT_DATA = (SID = orcl))
orcl_BEQ =
(DESCRIPTION =
(ADDRESS = (PROTOCOL = BEQ)(PROGRAM = /usr/oracle)
(argv0 = oracleorcl)
(args = '(DESCRIPTION =
(LOCAL=YES)(ADDRESS=(PROTOCOL=BEQ)))')
(envs =
'ORACLE_HOME=/usr/oracle,ORACLE_SID=orcl')
initorcl.ora
mts_dispatchers="tcp,1"
mts_max_dispatchers=3
mts_servers=1
mts_max_servers=5
mts_service=orcl
mts_listener_address="(ADDRESS=(PROTOCOL=tcp)(Host=pcstar)(Por
t=1521))"
If anybody started server in Multi-Thread mode, mail me
[email protected]
Best Regards!
Gennady Saldiga
null

Yes, the MTS for TCP protocol does not work. A patch will be
released soon for the production release with the fix for
the MTS problem.
Maturi
Satoshi Hirai (guest) wrote:
: Gennady Saldiga (guest) wrote:
: : I installed Oracle 8.0.5.0.0 on Linux RedHat 5.1
: : But I cann't startup database in multi-threaed mode.
: : When I try to startup DB the errors follow
: : SVRMGR> startup;
: : ORA-00101: invalid specification for system parameter
: : MTS_DISPATCHERS
: : ORA-00102: network protocol
: : (ADDRESS=(PARTIAL=YES)(PROTOCOL=tcp)) cannot be used by
: : dispatchers
: : My configuration files are:
: : listener.ora
: : LISTENER =
: : (ADDRESS_LIST =
: : (ADDRESS= (PROTOCOL= IPC)(KEY= orcl))
: : (ADDRESS= (PROTOCOL= IPC)(KEY= PNPKEY))
: : (ADDRESS= (PROTOCOL= TCP)(Host=
: : pcstar.kharkov.ua)(Port= 1521))
: : SID_LIST_LISTENER =
: : (SID_LIST =
: : (SID_DESC =
: : (GLOBAL_DBNAME= pcstar.kharkov.ua)
: : (ORACLE_HOME= /usr/oracle)
: : (SID_NAME = orcl)
: : (SID_DESC =
: : (SID_NAME = extproc)
: : (ORACLE_HOME = /usr/oracle)
: : (PROGRAM = extproc)
: : STARTUP_WAIT_TIME_LISTENER = 0
: : CONNECT_TIMEOUT_LISTENER = 10
: : TRACE_LEVEL_LISTENER = OFF
: : tnslistener working normally
: : tnsnames.ora
: : extproc_connection_data =
: : (DESCRIPTION =
: : (ADDRESS = (PROTOCOL = IPC)(KEY = orcl))
: : (CONNECT_DATA = (SID = extproc))
: : orcl =
: : (DESCRIPTION =
: : (ADDRESS = (PROTOCOL= TCP)(Host=
: : pcstar.pcstar.kharkov.ua)(Port= 1521))
: : (CONNECT_DATA = (SID = orcl))
: : orcl_BEQ =
: : (DESCRIPTION =
: : (ADDRESS = (PROTOCOL = BEQ)(PROGRAM = /usr/oracle)
: : (argv0 = oracleorcl)
: : (args = '(DESCRIPTION =
: : (LOCAL=YES)(ADDRESS=(PROTOCOL=BEQ)))')
: : (envs =
: : 'ORACLE_HOME=/usr/oracle,ORACLE_SID=orcl')
: : initorcl.ora
: : mts_dispatchers="tcp,1"
: : mts_max_dispatchers=3
: : mts_servers=1
: : mts_max_servers=5
: : mts_service=orcl
mts_listener_address="(ADDRESS=(PROTOCOL=tcp)(Host=pcstar)(Por
: : t=1521))"
: : If anybody started server in Multi-Thread mode, mail me
: : [email protected]
: : Best Regards!
: : Gennady Saldiga
: Hi!
: Same problem occured on my environment (Debian GNU/Linux 2.0).
: But I succeeded to start Multi-thread server on ipc protocol.
: My current configuration file (mts_* in init.ora) as follows:
: mts_dispatchers="ipc,1"
: mts_max_dispatchers=10
: mts_servers=1
: mts_max_servers=10
: mts_service=orcl
: # I confirmed mts_listener_address syntax by manual and
: # v$parameter.
: # Net8 Admn man says: If you have multiple MTS_LISTENER_ADDRESS
: # parameters, they must be adjacent to each other in your
: # initialization file.
mts_listener_address="(ADDRESS=(PROTOCOL=TCP)(host=j-00872)(port=
: 1521))"
: mts_listener_address="(ADDRESS=(PROTOCOL=IPC)(KEY=orcl))"
: So I tested MTS_DISPATCHERS parameter's other syntax.
: The test results are:
: # mts_dispatchers="ipc,1"
: # OK
: # mts_dispatchers="tcp,1"
: # ORA-00101,ORA-00102 occured
: # mts_dispatchers="TCP,1"
: # ORA-00101,ORA-00102 occured
: # mts_dispatchers="ipc,1","tcp,1"
: # ORA-00101,ORA-00102 occured
: # mts_dispatchers="(ADDRESS=(PARTIAL=YES)(PROTOCOL=tcp))"
: # ORA-00101,ORA-00102 occured
: # mts_dispatchers="(ADDRESS=(PARTIAL=NO)(PROTOCOL=tcp))"
: # ORA-00101,ORA-00102 occured
: # mts_dispatchers="(ADDRESS=(PARTIAL=YES)(PROTOCOL=ipc))"
: # OK
: # mts_dispatchers="(PROTOCOL=IPC) (DISPATCHERS=3)"
: # OK
: # mts_dispatchers="(PROTOCOL=TCP) (DISPATCHERS=3)"
: # ORA-00101,ORA-00102 occured
: # mts_dispatchers="(ADDRESS=(PROTOCOL=IPC)(KEY=orcl))
: (dispatchers=3)"
: # OK
mts_dispatchers="(ADDRESS=(PROTOCOL=TCP)(host=j-00872)(port=1521)
: ) (dispatcher
: s=3)"
: # ORA-00101,ORA-00102 occured
mts_dispatchers="(description=(ADDRESS=(PROTOCOL=IPC)(KEY=orcl))(
: connect_data=
: (sid=orcl))) (dispatchers=3)"
: # OK
mts_dispatchers="(description=(ADDRESS=(PROTOCOL=TCP)(host=j-0087
: 2)(port=1521)
: )(connect_data=(sid=orcl))) (dispatchers=3)"
: # ORA-00101,ORA-00102 occured
: ### While the test, sometimes ORA-00472 (ORA-00472: PMON
process
: ### terminated with error) occured when instance shutdown.
: ### I think the error reported in another message
: ### on the same thread.
: It seems dispatcher is not binded to tcp protocol adapter.
: Does anybody have more information about Multi-thread server
: using TCP protocol.
: ### Please forgive my bad english.
: Thank you.
: Satoshi Hirai
null

The problem about multi-thread in java application

i have problem with the multi-thread in java application, i don't know how to stop and restart a thread safely, because the function thread.stop(),thread.suspend() are both deprecated.
now what i can only do is making the thread check a flag(true or false) to determine whether to start or to stop, but i think this thread will always be in the memory and maybe it will lower the performance of the system, as the program i am developping is working under realtime enviorement.
please help me about it. thanks !

hi,
you can stop a thread by exiting it's run()-method which in terms can be done by checking the interrupted-flag:
public void run(){
while(interrupted()){ //if the thread consists of a loop
or
public void run(){
if(interrupted())return;
if(interrupted())return;
or by the use of the return-statement anywhere withing the run-method. Afterwards, that is when the thread is no longer needed, you clear all the references to the specific thread object by setting them to null:
Thread t;
... //working
t.interrupt(); //interrupting
while(t.isAlive()){
Thread.yield(); //wait till thread t has stopped
t=null;
best regards, Michael

Running flash full screen while using other apps

I run a 3 monitor setup on Win7x64. I would like to watch shows, eg Hulu, while working on other stuff on the other monitors. Any time I switch focus to another program though it drops back down into the browser. Is there a way to keep it running full screen while working with other programs?

Hi, here is a thread where it was discussed and the person that answered should know.
http://forums.adobe.com/message/2716538#2716538
You might take a look on the right hand side under "More like this" just to see what others have to say even tho there doesn't seem to be a solution to this.
Thanks,
eidnolb

Crystal Report XI u2013 Multi Thread - function PEOpenEngineEx failed. Reason:

In Crystal Report XI u2013 Multi Thread - function PEOpenEngineEx failed. Reason: Report engine not opened
Hi
I am using Crystal report XI with Delphi 7
OS: Windows XP.
Delphi 7
CR Version: Crystal Report XI
In Crystal Report XI While calling PEOpenEngineEx() by setting Engine option as multi thread, It failed with error message u201CError:512 Report Engine Not Openedu201D
Code Change in Delphi 7 UCrpe32.pas (Crystal Reports XI Release 1 - Service Pack 3 and Service Pack 4)
aEngineOptions.openEngineType := PE_OE_MULTI_THREADED;
FEngineOpened := FCrpeEngine.PEOpenEngineEx(EngineOptions);
I tried the same with Crystal Report 8.5 (above mentioned code change) Function PEOpenEngineEx() working fine.
How to overcome this error to make work Multi Thread using CR XI?

I found that it is bug Release 2 and the script server_patch_xir2 resolved it.

Multi-threaded application crashing the VM

Hi,
I have a multi-threaded (about 120 threads) application which crashes without after running for a while.
I get this in the windows event viewer
Faulting application java.exe, version 0.0.0.0, faulting module kernel32.dll, version 5.2.3790.0, fault address 0x000017b1.
Anyone knows why this would happen?
- vineet

Hi Alexis,
Thanks for the response to my post!!
Which version of the JVM?C:\>java -version
java version "1.4.2_05"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.4.2_05-b04)
Java HotSpot(TM) Client VM (build 1.4.2_05-b04, mixed mode)
Are you using the -server option?I was not using this option earlier but even on using this the jvm crashes after running for sometime.
I am using these jvm options now -
java -server -Xss128K -Xms256M -Xmx512M
- vineet

Some general questions about multi-threading

Hey Everybody,
I have a dilemma with a multi-threaded program that I have written.
Well to be truthful I actually wrote the program with no consideration whatsoever for multithreading.
As a result of this complete lack of concern I get a completely hung user interface.
My program performs a lot of network communications over URL��s and also writes information from URL��s to disk. The combination of networking and I/O in my program and the fact that I have not built multi-threading into the program has lead to complete failure of the user interface. When I say complete failure I mean complete failure. If it were only button��s not responding then I wouldn��t be all that worried, however the entire drawing area of my programs ��Frame�� completely freezes. It��s cool if nothing is maximized or minimized over the frame but as soon as this happens my programs drawing area has a ��serious hang over!��.
I have begun learning about threads, in principle they sound wicked however in practice they have proven to be a brain tease (oops �K.. honesty).
The difficulty of threads should not be all that daunting to me, however I have a couple of very simple questions that I would love to have answered�K..anybody out there!!!!!!!!!
This is the normal basic method of running a thread that I have been attempting to incorporate into my program:
1). Extend the thread class,
2). Override the run() method in the subclass (created from step 1),
3). Create an instance of the subclass,
4). Call the start() method on the instance (from step 3).
I have read that every statement the thread will execute is contained within it��s run() method.
Question 1). This being the case is it possible to have member variables or methods inside a class that extends thread? Please explain!
Question 2). Can a class that extends thread contain a constructor? Please explain!
Question 3). If a subclass of thread cannot contain a constructor as I assume to be the case then how can code executing within the newly spawned thread reference information from the object that spawned it?
If anybody out there on the great net can answer even half of one of these questions I will be more than grateful. Thanks for your time, and rock on Java!
David

Thread t = new Thread(MyRunnableDerivedClass);
t.start();I hope it is understood that MyRunnableDerivedClass is actually an object of the MyRunnableDerivedClass. sorry for the confusion.
so here's a thread that reads from a file using constructors, member variables, other funcs. It's not optimal but shows use of all of the above. I just typed this in so there are probably syntax errors, but you should get the point.
public class ThreadedFileReader implements Runnable
    private File m_File;
    byte[] contents = new byte[0];
    public ThreadedFileReader( File f )
       m_File = f;
    public void run()
        BufferedInputStream bis = null;
        try
            bis = new BufferedInputStream( new FileInputStream( m_File ));
            int avail = bis.available();
            while (avail > 0)
                int oldLen = contents.length();
                contents = expand( contents, avail );
                bis.read( contents, oldLen, avail );
                avail = bis.available();
        catch (Exception e)
        { //do something witty
        finally
            try{ if (bis != null) bis.close(); } catch (Exception e){}
   private byte[] expand( byte[] oldBuf, int addedLen )
      byte[] newBuf = new char[oldBuf.length + addedLen];
      System.arrayCopy( newBuf, 0, oldBuf, 0, oldBuf.length );
      return newBuf;
   public byte[] getContents()
       return contents;
//here's where we use it
File f = new File( "c:\myfile" );
ThreadedFileReader tfr = new ThreadedFileReader( f );
Thread t = new Thread( tfr );
t.start();
t.join();
// At this point the thread has died, but the thread object still exists
byte [] data = tfr.getContents();

Refreshing Screen while Multi-Threading

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