1 package com.threadcopyfile; 2 3 /** 4 * @author lisj 5 * 實現多線程的同時復制 6 * 調用多個線程同時復制各自的模塊 7 */ 8 public class threadCopy { 9 10 11 public static void main (String args[]){ 12 13 ThreadCopyFile a=new ThreadCopyFile(1); //實例化多個線程 14 ThreadCopyFile b=new ThreadCopyFile(2); 15 ThreadCopyFile c=new ThreadCopyFile(3); 16 Thread down1 = new Thread(a); 17 down1.start(); //啟動線程1,2,3 18 Thread down2 = new Thread(b); 19 down2.start(); // 20 Thread down3 = new Thread(c); 21 down3.start(); 22 23 } 24 25 }
1 package com.threadcopyfile; 2 3 import java.io.File; 4 import java.io.IOException; 5 import java.io.RandomAccessFile; 6 7 /** 8 * @author lisj 9 * 實現復制功能 10 * 當線程調用的時候開始復制 11 */ 12 public class ThreadCopyFile extends Thread{ 13 14 int i; //定義全局變量i，識別復制的模塊數 15 16 ThreadCopyFile(int i) 17 { 18 this.i=i; 19 } 20 21 22 /** 23 * 文件復制函數 24 * 利用RandomAccessFile類實現文件的讀和寫 25 * 實現復制文件的功能 26 */ 27 public void run() { 28 29 System.out.println("線程"+i+"運行中。。。"); 30 31 File ofile=new File("e:/java亂碼處理.txt"); 32 File nfile=new File("e:/456.txt"); //定義目的路徑以及文件名 33 34 try { 35 36 RandomAccessFile in=new RandomAccessFile(ofile,"rw"); 37 38 long length=in.length()/3; 39 40 RandomAccessFile out=new RandomAccessFile(nfile,"rw"); 41 int count=0; 42 int len=0; 43 byte[] b= new byte[2048]; 44 in.seek(length*(i-1)); //設置讀文件偏移位置 45 out.seek(length*(i-1)); //設置寫文件偏移位置 46 while(((len=in.read(b))!=-1)&&(count<=(int)length)){ //讀取文件內容設置寫文件停止條件 47 48 out.write(b, 0, len); 49 count=count+len; 50 51 }//寫出文件內容 52 53 } catch (IOException e) { 54 55 e.printStackTrace(); 56 } 57 58 System.out.println("線程"+i+"復制完成！"); 59 } 60 61 }