PropertyChangeSupport

import java.beans.PropertyChangeListener;
import java.beans.PropertyChangeSupport;

/**
 *
 * @author max
 */
public class Domain{
        protected String id;
        protected String name;
        protected String desName;

        protected PropertyChangeSupport listeners = new PropertyChangeSupport(this);

        public String getId() {
            return id;
        }

        public void setId(String id) {
            this.id = id;
            firePropertyChange("Domain.id", null, id);
        }

        public String getDesName() {
           return desName;
        }

        public void setDesName(String desName) {
            this.desName = desName;
            firePropertyChange("Domain.desName", null, desName);
        }

        public String getName() {
            return name;
        }

        public void setName(String name) {
            this.name = name;
            firePropertyChange("Domain.name", null, name);
        }

        public void addPropertyChangeListener(PropertyChangeListener listener) {
            listeners.addPropertyChangeListener(listener);
        }

        public void firePropertyChange(String propName, Object oldValue, Object newValue) {
            listeners.firePropertyChange(propName, oldValue, newValue);
        }

        public void removePropertyChangeListener(PropertyChangeListener listener) {
            listeners.removePropertyChangeListener(listener);
        }
    }

 

java 代码

1. public class SimpleObserver implements PropertyChangeListener {   
2.        
3.     ....   
4.        
5.     @Override  
6.     public void propertyChange(PropertyChangeEvent evt) {   
7.         if(evt.getPropertyName().equals("Domain.name")){   
8.             //do some work   
9.         }   
10.     }   
11.        
12. }  

下面是个简单的测试类：

java 代码

1. public class SimpleTest{   
2.     public static void main(String[] args) {   
3.         SimpleObserver observer = new SimpleObserver();   
4.         Domain domain = new Domain();   
5.         domain.addPropertyChangeListener(observer);   
6.         domain.setName("yangsq");   
7.         ......   
8.     }   
9. }  

很显然，可以观察到SimpleObserver中propertyChange方法的执行。