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DelayedDocumentListener.java

import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.Timer;
import javax.swing.event.DocumentEvent;
import javax.swing.event.DocumentListener;

public class DelayedDocumentListener implements DocumentListener {

    private final Timer timer;
    private DocumentEvent lastEvent;

    public DelayedDocumentListener(DocumentListener delegate) {
        this(delegate, 500);
    }

    public DelayedDocumentListener(final DocumentListener delegate, int delay) {
        timer = new Timer(delay, new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                timer.stop();
                if (lastEvent.getType() == DocumentEvent.EventType.INSERT) {
                    delegate.insertUpdate(lastEvent);
                } else if (lastEvent.getType() == DocumentEvent.EventType.REMOVE) {
                    delegate.removeUpdate(lastEvent);
                } else {
                    delegate.changedUpdate(lastEvent);
                }
            }
        });
    }

    private void storeUpdate(DocumentEvent e) {
        lastEvent = e;
        timer.restart();
    }

    @Override
    public void insertUpdate(DocumentEvent e) {
        storeUpdate(e);
    }

    @Override
    public void removeUpdate(DocumentEvent e) {
        storeUpdate(e);
    }

    @Override
    public void changedUpdate(DocumentEvent e) {
        storeUpdate(e);
    }
}