how to stop thread A from thread B using a button
Hi,
I have created a thread A which in turn creates a thread B.
Is it possible to press a button on thread B that stops execution of thread A (and consequently thread B, of course)?
More specifically, thread A is a client thread that waits for server data. If it takes too long I would like to give the opportunity to the user to stop waiting by pressing "cancel" button on thread B (which is actually a dialog box with a "please wait" message)
I can attach my code if requested.
[511 byte] By [
xpantaa] at [2007-11-27 10:03:28]
# 1
What about interrupting it ?
http://java.sun.com/javase/6/docs/api/java/nio/channels/InterruptibleChannel.html
Something like:
private static final class B implements Runnable {
private final A a;
public B(A t) {
a = t;
}
public void run() {
int res = JOptionPane.showConfirmDialog(null, "Cancel waiting ?", "...", JOptionPane.CANCEL_OPTION);
if (res == JOptionPane.OK_OPTION)
a.interrupt();
}
}
# 2
Thanks for your code. I am trying it right now...
The problem is that I actually want to interrupt B. Here is my code
class ThreadedAction extends AbstractAction implements Runnable{
public void actionPerformed(ActionEvent e){
obj = e.getSource();
if (worker != null)
return;
worker = new Thread(this);
worker.start();
}
public void run()
{
if (obj == SolveBtn)
{
try{
CylonBar bar = new CylonBar((JFrame)getRootPane().getParent());
bar.start(); // << bar is a threaded dialog box.
Result = nm.solveHEP(table); // <<-- nm is the object that communicates with the server waiting for a result. If it takes too long this thread should be stopped by the user
bar.setStopFlag(true);
}
catch(IOException ioe)
{}
}
worker = null;
}
}
and this is the code of the threaded dialog box
public class CylonBar extends Thread {
JProgressBar bar = new JProgressBar();
JFrame frame;
JLabel label = new JLabel("<html><b>Please Wait...</b></html>"
);
JButton CancelBtn = new JButton("Cancel");
volatile Boolean stopflag = false;
public CylonBar(JFrame parent)
{
frame = new JFrame();
frame.setSize(300, 200);
label.setForeground(Color.ORANGE);
frame.getContentPane().setBackground(Color.BLUE);
frame.getContentPane().setLayout(new BorderLayout(2,2));
frame.getContentPane().add(bar, BorderLayout.CENTER);
frame.setLocation(parent.getLocationOnScreen().x + parent.getWidth()/2 - frame.getSize().width/4, parent.getLocationOnScreen().y + parent.getHeight()/2 - frame.getSize().height/4);
frame.add(bar, BorderLayout.NORTH);
frame.add(label, BorderLayout.CENTER);
frame.add(CancelBtn, BorderLayout.SOUTH);
bar.setIndeterminate(true);
bar.setForeground(Color.GREEN);
frame.pack();
frame.setVisible(true);
CancelBtn.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent e)
{
Thread.currentThread().interrupt(); // <<-- it doesn't work!!!
}
});
}
public void run()
{
while (true)
{
try {
sleep(1000);
if(stopflag){
//Thread.currentThread().interrupt();
frame.setVisible(false);
}
} catch (InterruptedException e){}
}
}
public void setStopFlag(boolean t)
{
this.stopflag = t;
}
}
I would like to cancel the operation ThreadedAction is doing using a button on the threaded dialog box "CylonBar"
