[Demonstration 1]

[Buggy Method]
public void testGetListeners() {
    final TestListener testListener = new TestListener();
    model.listenerList.add(TestListener.class, testListener);
    assertTrue(Arrays.asList(model.getListeners(TestListener.class)).contains(testListener));
}

[Buggy Hunk]
model.listenerList.add(TestListener.class, testListener);

[Patch]
model.addChangeListener(testListener);

[Demonstration 2]

[Buggy Method]
protected boolean isLocked(Object o) {
    return o instanceof ILockableContainer && ((ILockableContainer) o).isLocked();
}

[Buggy Hunk]
protected boolean isLocked(Object o){

[Patch]
protected static boolean isLocked(Object o){