bug6872503.java 文件源码

static boolean isLayerEventControllerAdded() {
    Toolkit toolkit = Toolkit.getDefaultToolkit();
    AWTEventListener layerEventController = null;
    for (AWTEventListener listener : toolkit.getAWTEventListeners()) {
        if (listener instanceof AWTEventListenerProxy) {
            listener = ((AWTEventListenerProxy)listener).getListener();

        }
        if ("LayerEventController".equals(listener.getClass().getSimpleName())) {
            if (layerEventController != null) {
                throw new RuntimeException("Duplicated LayerEventController");
            }
            layerEventController = listener;
        }
    }
    boolean ret = layerEventController != null;
    if (ret) {
        System.out.println("LayerEventController found");
    } else {
        System.out.println("No LayerEventController");
    }
    return ret;
}