For registering Java runnables as event listeners on GWT DOM elements

NativeDomEvents.java

/**
 * For registering Java {@link Runnable runnables} as event listeners on GWT DOM elements.
 * <p>
 * This class allows for registering listeners for all DOM events including those not supported by GWT.
 */
public class NativeDomEvents {

    public static native void addEventListener(Element element, String event, Runnable listener) /*-{

        var eventListener = function() {
	    listener.@java.lang.Runnable::run()();
        };
    	
        if (element.addEventListener) {
            element.addEventListener(event, eventListener, false);
        } else if (element.attachEvent) {
            element.attachEvent('on' + event, eventListener);
        }

        }-*/;
}