joinedpeergroups.java

一个基于NetBeans平台开发的

/**唯一的目的是：
 *记录组信息，为了发布或加入组后，
 *生成taskInfo对象使用其中的数据，
 *在RCF中维护加入组的数据是taskList，它是一个Victor。
 */

package com.sinpool.rivercrescent.BufferZone; 

import java.util.Hashtable;
import java.io.*;

public class JoinedPeerGroups extends Hashtable implements Serializable{
	private Hashtable ht = null;
	private int groupNums = 0;
	
	public JoinedPeerGroups(int i){
		this.ht = new Hashtable(i);
	}
	
	public synchronized void putGroup(Object key,Object value){
		ht.put(key,value);
                groupNums++;
	}
	
	public synchronized Object getGroup(Object key){
		return ht.get(key);
	}
	
	public synchronized boolean haveKey(Object key){
		return ht.containsKey(key);
	}
	
	public synchronized void delGroup(Object key){
		ht.remove(key);
                groupNums--;
	}
	
	public synchronized int getGroupNums(){
		return ht.size();
	}
        public boolean  dataWriteToDisk(){
		String fileName = "taskobj\\" + "joinedG.cfg";
		
		try{
			File file = new File(fileName);
			new File("taskobj").mkdir();
			FileOutputStream fos = new FileOutputStream(file);
			ObjectOutputStream oos = new ObjectOutputStream(fos);
			
			oos.writeObject(this);
			oos.flush();
			
			oos.close();
			fos.close();
		}catch (IOException ioe) {return false;}
		
		return true;
        }
	public static JoinedPeerGroups dataReadFromDisk(){
		JoinedPeerGroups result = null;
		try{
			File file = new File("taskobj\\" + "joinedG.cfg");
			FileInputStream fis = new FileInputStream(file);
			ObjectInputStream ois = new ObjectInputStream(fis);
			
			result = (JoinedPeerGroups)ois.readObject();
			
			ois.close();
			fis.close();
		}catch (IOException ioe) {System.out.println("出现IO错误！");return null;}
		catch (ClassNotFoundException cfe) {System.out.println("从流中检索的对象没有找到所属的类！");return null;}
		
		return result;
	}
}