Java tutorial
package com.chinarewards.gwt.license.client.mvp.impl; import com.chinarewards.gwt.license.client.mvp.ErrorHandler; import com.google.gwt.user.client.Window; import com.google.inject.Singleton; @Singleton public class WindowAlertErrorHandler implements ErrorHandler { public void alert(String message) { Window.alert(message); } public void alert(String message, Throwable e) { // custom alert message Window.alert(message + "\n\n" + e.toString()); } }