Java 自定義監聽器監聽屬性變化

Java 自定義監聽器監聽屬性變化

1. import java.util.EventObject;
3. public class MyEvent extends EventObject
4. {
5. private Object obj;
6. private String sName;
8. public MyEvent(Object source,String sName)
9. {
10. super(source);
11. this.obj=source;
12. this.sName=sName;
13. }
15. public Object getObj()
16. {
17. return obj;
18. }
20. public String getsName()
21. {
22. return sName;
23. }
24. }
26. import java.util.EventListener;
28. public interface MyEventListener extends EventListener
29. {
31. public void handleEvent (MyEvent me);
33. }
36. import java.util.Iterator;
37. import java.util.Vector;
39. import demo.DemoEvent;
41. public class MyEventSource
42. {
43. private Vector list=new Vector();
44. private String sName = "";
47. public MyEventSource()
48. {
49. super();
50. }
51. public void addMyEventListener(MyEventListener me)
52. {
53. list.add(me);
54. }
55. public void deleteMyEventListener(MyEventListener me)
56. {
57. list.remove(me);
58. }
59. public void notifyMyEvent(MyEvent me)
60. {
61. Iterator it=list.iterator();
62. while(it.hasNext())
63. {
64. ((MyEventListener) it.next()).handleEvent(me);
65. }
66. }
67. public void setName(String str)
68. {
69. boolean bool = false;
70. if (str == null && sName != null)
71. bool = true;
72. else if (str != null && sName == null)
73. bool = true;
74. else if (!sName.equals(str))
75. bool = true;
76. this.sName = str;
77. // 如果改變則執行事件
78. if (bool)
79. notifyMyEvent(new MyEvent(this, sName));
80. }
81. public String getsName()
82. {
83. return sName;
84. }
86. }
90. public class Test implements MyEventListener
91. {
92. public Test()
93. {
94. MyEventSource mes = new MyEventSource();
95. mes.addMyEventListener(this);
96. mes.setName("niu");
97. }
99. public static void main(String args[])
100. {
101. new Test();
102. }
104. public void handleEvent(MyEvent me)
105. {
106. System.out.println(me.getSource());
107. System.out.println(me.getsName());
108. }
109. }