摘要：
一个好方法是封装监听器类，并使用addListener（）方法动态添加监听器2。代码1。测验Java语言
一、概述
childe类中的是关联监听者dad的，若要再增加监听者，会很不方便，且要修改代码。好的方法是封装监听者类，用addListener()方法动态添加监听者
二、代码
1.Test.java
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 | classWakenUpEvent{ privatelongtime; privateString location; privateChild source; publicWakenUpEvent(longtime, String location, Child source) { super(); this.time = time; this.location = location; this.source = source; } publiclonggetTime() { returntime; } publicvoidsetTime(longtime) { this.time = time; } publicString getLocation() { returnlocation; } publicvoidsetLocation(String location) { this.location = location; } publicChild getSource() { returnsource; } publicvoidsetSource(Child source) { this.source = source; } }classChild implementsRunnable { privateList<WakenUpListener> wakenUpListeners = newArrayList<WakenUpListener>(); publicvoidaddWakenUpListener(WakenUpListener wul){ wakenUpListeners.add(wul); } publicvoidwakeUp(){ for(inti = 0; i < wakenUpListeners.size(); i++){ WakenUpListener l = wakenUpListeners.get(i); l.actionToWakenUp(newWakenUpEvent(System.currentTimeMillis(), "bed", this)); } } @Override publicvoidrun() { try{ Thread.sleep(3000); } catch(Exception e) { e.printStackTrace(); } wakeUp(); }}interfaceWakenUpListener { publicvoidactionToWakenUp(WakenUpEvent e);}classDad implementsWakenUpListener { publicvoidactionToWakenUp(WakenUpEvent e) { System.out.println("Fedd the child"); } }classGrandFather implementsWakenUpListener { publicvoidactionToWakenUp(WakenUpEvent e) { System.out.println("抱孩子"); } }publicclassTest { publicstaticvoidmain(String[] args) { Child c = newChild(); c.addWakenUpListener(newDad()); c.addWakenUpListener(newGrandFather()); newThread(c).start(); }} |
三、运行结果
