Java中实现回调过程

原文很长，事实上很简单，写个大概框架就可以了。 首先定义一个接口，产生事件的类包含这样一个类 public interface InterestingEvent { // This is just a regular method so it can return something or // take arguments if you like. public void interestingEvent (); } public class EventNotifier｛ private InterestingEvent ie; private boolean somethingHappened; public EventNotifier (InterestingEvent event) { // Save the event object for later use. ie = event; // Nothing to report yet. somethingHappened = false; } //... public void doWork () { // Check the predicate, which is set elsewhere. if (somethingHappened) { // Signal the even by invoking the interface's method. ie.interestingEvent (); } //... } // ... ｝ 然后被激活的事件处理就实现这个接口就可以了。 public class CallMe implements InterestingEvent { private EventNotifier en; public CallMe () { // Create the event notifier and pass ourself to it. en = new EventNotifier (this); } // Define the actual handler for the event. public void interestingEvent () { // Wow! Something really interesting must have occurred! // Do something... } //... }