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<TITLE>Determining When an Object Is No Longer Used
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<h3>
e107.
Determining When an Object Is No Longer Used</h3>
A weak reference is used to determine when an object
is no longer being referenced.
<pre>
// Create the weak reference.
ReferenceQueue rq = new ReferenceQueue();
WeakReference wr = new WeakReference(<font color="#0066ff"><i>object</i></font>, rq);
// Wait for all the references to the object.
try {
while (true) {
Reference r = rq.remove();
if (r == wr) {
// Object is no longer referenced.
}
}
} catch (InterruptedException e) {
}
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Related Examples
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e106. <a class="eglink" href="SoftRef.html?l=rel">
Holding onto an Object Until Memory Becomes Low
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e108. <a class="eglink" href="PhantomRef.html?l=rel">
Determining When an Object Will Be Reclaimed
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