sketchmodel.java

用Java实现的网络画图程序

import java.util.*;
import javax.swing.*;
import java.io.*;

class SketchModel  extends Observable implements Serializable{
	
	protected LinkedList elementList=new LinkedList();
	
	synchronized public boolean remove(Element element){
		boolean removed=elementList.remove(element);
		if(removed){
			setChanged();
			notifyObservers(element.getBounds());
		}
		return removed;
	}


	synchronized public void add(Element element){
		elementList.add(element);
		setChanged();
		notifyObservers(element.getBounds());
	}


	synchronized public Iterator getIterator(){
		return elementList.listIterator();
	}




}