simplemodel.java

java swing 开发代码

//  SimpleModel.java
// An example of a custom data model that could be used in any MVC
// scenario.
//
package	jswing.ch28;

import javax.swing.event.*;

public class SimpleModel implements SimpleModelInterface
{
    protected transient ChangeEvent changeEvent = null;
    protected EventListenerList listenerList = new EventListenerList();

    private int value = 0;
    private boolean activated = false;

    public SimpleModel() { }
    public SimpleModel(int v) { value = v; }
    public SimpleModel(boolean b) { activated = b; }
    public SimpleModel(int v, boolean b) { 
        value = v;
        activated = b;
    }

    public int getValue() { return value; }

    public synchronized void setValue(int v) {
       if (v != value) {
            value = v;
           fireChange(); 
       }
    }

    public boolean isActivated() { return activated; }

    public synchronized void setActivated(boolean b) {
       if (b != activated) {
           activated = b;
           fireChange(); 
       }
    }

    public void addChangeListener(ChangeListener l) {
        listenerList.add(ChangeListener.class, l);
    }
    
    public void removeChangeListener(ChangeListener l) {
        listenerList.remove(ChangeListener.class, l);
    }

    public ChangeListener[] getChangeListeners() {
        return (ChangeListener[])listenerList.getListeners(ChangeListener.class);
    }

    protected void fireChange() 
    {
        Object[] listeners = listenerList.getListenerList();
        for (int i = listeners.length - 2; i >= 0; i -=2 ) {
            if (listeners[i] == ChangeListener.class) {
                if (changeEvent == null) {
                    changeEvent = new ChangeEvent(this);
                }
                ((ChangeListener)listeners[i+1]).stateChanged(changeEvent);
            }          
        }
    }   

    public String toString()  {
        String modelString = "value=" + getValue() + ", " +
            "activated=" + isActivated();
        return getClass().getName() + "[" + modelString + "]";
    }
}