savetaskinfo.java

一个简单的多线程下载程序

package com.network.flashget;

import java.io.*;
import java.util.LinkedList;

/**
 *用于向文件中存储信息
 **/
class SaveTaskInfo
{
	File downFile;
	File finishedFile;
	File deletedFile;
	File indexFile = new File(".\\Info\\index.txt");
	
	LinkedList downList = new LinkedList();
	LinkedList finishedList = new LinkedList();
	LinkedList deletedList =  new LinkedList();
	/**
	 *初始化一些变量
	 **/
	SaveTaskInfo(LinkedList a,LinkedList b,LinkedList c,int index)
	{
		downFile = new File(".\\Info\\Down"+index+".txt");
		finishedFile = new File(".\\Info\\Fini"+index+".txt");
		deletedFile = new File(".\\Info\\Delt"+index+".txt");
		
		this.downList = a;
		this.finishedList = b;
		this.deletedList = c;
		
		//若文件不存在，则创建文件进行存储-------------------------------------
		try
		{
			if(!downFile.exists())
			{
				downFile.createNewFile();		
			}
			if(!finishedFile.exists())
			{
				finishedFile.createNewFile();		
			}
			if(!deletedFile.exists())
			{
				deletedFile.createNewFile();		
			}
		}
		catch(IOException e)
		{
			e.printStackTrace();
		}
	}
	
	
	//连接文件存储信息------------------------------------------------------------
	public void saveInfo()
	{
		//正在下载文件信息存储------------------------------------------------------
		try
		{
			FileOutputStream fos = new FileOutputStream(downFile);
			ObjectOutputStream oos = new ObjectOutputStream(fos);
			System.out.println(downList.size());
			
			writeToFile(downList,oos);
		}
		catch(Exception e1)
		{
			e1.printStackTrace();
		}
		
		//已下载文件信息存储--------------------------------------------------------
		try
		{
			FileOutputStream fos = new FileOutputStream(finishedFile);
			ObjectOutputStream oos = new ObjectOutputStream(fos);
			System.out.println(finishedList.size());
			
			writeToFile(finishedList,oos);
		}
		catch(Exception e2)
		{
			e2.printStackTrace();
		}
		
		//已删除文件信息存储--------------------------------------------------------
		try
		{
			FileOutputStream fos = new FileOutputStream(deletedFile);
			ObjectOutputStream oos = new ObjectOutputStream(fos);
			System.out.println(deletedList.size());
			
			writeToFile(deletedList,oos);
		}
		catch(Exception e3)
		{
			e3.printStackTrace();
		}
	}
	
	
	/**
	 *用于写入对象信息---------------------------------------------------------------------
	 **/
	public void writeToFile(LinkedList list,ObjectOutputStream oos)
	{
		try
		{			
			//若任务链表为空，则向文件中写入空标志
			if(list.size()==0)
			{
				oos.writeObject("empty");
				oos.flush();
			}
			
			//若任务链表不为空，则将对象写入文件中
			else
			{
				//写入不为空的标志----------------------------------------------------------
				oos.writeObject("Not Empty");
				oos.flush();
				
				//写入对象信息---------------------------------------------------------------
				for(int i = 0;i < list.size();i++)
				{
					oos.writeObject(list.get(i));
					oos.flush();
				}
				
				//写入文件结束 标志----------------------------------------------------------
				oos.writeObject("end");
				oos.flush();
			}
			oos.close(); 
		}
		catch(Exception e5)
		{
			e5.printStackTrace();
		}		
	}
	
	/**
	 *用于存入MainWindow中的index信息--------------------------------------------------------
	 **/
	public void saveIndex()
	{
		try
		{
			if(!indexFile.exists())
			{
				indexFile.createNewFile();		
			}
			
			FileOutputStream fos = new FileOutputStream(indexFile);
			System.out.println("Save index:"+MainWindow.index);
			fos.write(MainWindow.index);
			fos.close();
			
		}
		catch(IOException e)
		{
			e.printStackTrace();
		}
	}	
}