com.sun.javafx.binding.OrElseBinding Maven / Gradle / Ivy
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package com.sun.javafx.binding;
import java.util.Objects;
import javafx.beans.value.ObservableValue;
import javafx.util.Subscription;
public class OrElseBinding extends LazyObjectBinding {
private final ObservableValue source;
private final T constant;
public OrElseBinding(ObservableValue source, T constant) {
this.source = Objects.requireNonNull(source, "source cannot be null");
this.constant = constant;
}
@Override
protected T computeValue() {
T value = source.getValue();
return value == null ? constant : value;
}
@Override
protected Subscription observeSources() {
return source.subscribe(this::invalidate); // start observing source
}
}