java中的PropertyChangeSupport与PropertyChangeListener

java中的PropertyChangeSupport与PropertyChangeListener配合使用能够实现，绑定属性会在属性值发生变化时，通知所有相关的监听器。

javaBean：

package com.wang.test.property;

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

public class TestBean {

	protected final PropertyChangeSupport support = new PropertyChangeSupport(this);
	
	private String str;
	
	public String getStr() {
		return str;
	}

	public void setStr(String str) {
		support.firePropertyChange("str", this.str, str);
		this.str = str;
	}
	
	public void addPropertyChangeListener(PropertyChangeListener listener) {
		support.addPropertyChangeListener(listener);
	}
	
	public void removePropertyChangeListener(PropertyChangeListener listener) {
		support.removePropertyChangeListener(listener);
	}
}

 client：

package com.wang.test.property;

import java.beans.PropertyChangeEvent;
import java.beans.PropertyChangeListener;

public class PropertyChangeSupportTest {

    public static void main(String[] args) {  
    	
        TestBean test = new TestBean();
        test.setStr("ddddd");
        test.addPropertyChangeListener(new PropertyChangeListener1());
        test.setStr("yyyy");
        
        //test.addPropertyChangeListener(new PropertyChangeListener2());
    	//test.setStr("hhhhhhf");
    }  
      
    public static class PropertyChangeListener1 implements PropertyChangeListener{

		@Override
		public void propertyChange(PropertyChangeEvent evt) {
			System.out.println( "1:  " + evt.getPropertyName() + "   " + evt.getNewValue() + "   " + evt.getOldValue());
			
		}
    }
    
    public static class PropertyChangeListener2 implements PropertyChangeListener{

		@Override
		public void propertyChange(PropertyChangeEvent evt) {
			System.out.println( "2:  " + evt.getPropertyName() + "   " + evt.getNewValue() + "   " + evt.getOldValue());
			
		}
    }
}