Re: Synchronization when collecting data from the EDT?

Knute Johnson <>
Sat, 04 Jun 2011 17:50:08 -0700
On 06/04/2011 05:38 PM, Knute Johnson wrote:

If you want to remove some data from the EDT and use it in another
thread, does EventQueue.invokeLater() or invokeAndWait() constitute
happens before? I don't think it does, so in that case, if you need to
access some data from your GUI components and use that data on another
thread there has to be some synchronization.

Object obj = new Object(); // use for lock
String str;

EventQueue.invokeLater(new Runnable() {
public void run() {
synchronized (obj) {
str = someJTextField.getText();

Actually I don't think this will work either as the run() method isn't
called until some time later, the subsequent code won't block and the
data won't necessarily have been updated.

So if I use invokeAndWait(), is there any guarantee that an interrupt
won't happen before the run() method is started? An exception shouldn't
be a problem if all the code is contained in a synchronized block.



Knute Johnson

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