com.sun.javafx.binding.BindingHelperObserver Maven / Gradle / Ivy
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package com.sun.javafx.binding;
import java.lang.ref.WeakReference;
import javafx.beans.InvalidationListener;
import javafx.beans.Observable;
import javafx.beans.WeakListener;
import javafx.beans.binding.Binding;
public class BindingHelperObserver implements InvalidationListener, WeakListener {
private final WeakReference> ref;
public BindingHelperObserver(Binding binding) {
if (binding == null) {
throw new NullPointerException("Binding has to be specified.");
}
ref = new WeakReference<>(binding);
}
@Override
public void invalidated(Observable observable) {
final Binding binding = ref.get();
if (binding == null) {
observable.removeListener(this);
} else {
binding.invalidate();
}
}
@Override
public boolean wasGarbageCollected() {
return ref.get() == null;
}
}