java.beans.PropertyChangeListener

 1 import java.beans.PropertyChangeEvent;
 2 import java.beans.PropertyChangeListener;
 3 import java.beans.PropertyChangeSupport;
 4
 5 public class DemoBeans {
 6
 7     private String demoName;
 8     private String Version;
 9     PropertyChangeSupport listeners = new PropertyChangeSupport(this);
10
11     public DemoBeans() {
12         demoName = "initValue";
13         Version="v1000";
14     }
15
16
17     public String getDemoName() {
18         return demoName;
19     }
20
21
22     public void setDemoName(String demoName) {
23         String oldValue = this.demoName;
24         this.demoName = demoName;
25         //发布监听事件
26         firePropertyChange("demoName", oldValue, demoName);
27
28     }
29
30     public void setDemoVersion(String demoVersion) {
31         String oldVersion = this.Version;
32         this.Version = demoVersion;
33         //发布监听事件
34         firePropertyChange("demoVersion", oldVersion, demoVersion);
35
36     }
37     public void addPropertyChangeListener(PropertyChangeListener listener) {
38         listeners.addPropertyChangeListener(listener);
39     }
40
41     public void removePropertyChangeListener(PropertyChangeListener listener){
42         listeners.addPropertyChangeListener(listener);
43     }
44
45
46     /**
47      * 触发属性改变的事件
48      */
49     protected void firePropertyChange(String prop, Object oldValue, Object newValue) {
50         listeners.firePropertyChange(prop, oldValue, newValue);
51     }
52     public static void main(String[] args) {
53         DemoBeans beans = new DemoBeans();
54
55         beans.addPropertyChangeListener(
56                 new PropertyChangeListener(){
57             public void propertyChange(PropertyChangeEvent evt) {
58                  if(evt.getPropertyName().equals("demoVersion")){
59                      System.out.println("version_OldValue:"+evt.getOldValue());
60                      System.out.println("version_NewValue:"+evt.getNewValue());
61                      System.out.println("version_tPropertyName:"+evt.getPropertyName());
62                  }
63                  else
64                  {
65                      System.out.println("name_OldValue:"+evt.getOldValue());
66                      System.out.println("name_NewValue:"+evt.getNewValue());
67                      System.out.println("name_tPropertyName:"+evt.getPropertyName());
68                  }
69
70             }});
71
72
73         beans.setDemoName("test");
74         beans.setDemoVersion("v2000");
75
76     }
77 }