java第四次作业

import java.io.BufferedInputStream;

import java.io.BufferedOutputStream;

import java.io.File;

import java.io.FileInputStream;

import java.io.FileNotFoundException;

import java.io.FileOutputStream;

import java.io.IOException;

import org.junit.Test;

public class CopyFile {    

@Test  

     public void testCopyFile(){    

     long start = System.currentTimeMillis();    

     String src="C:\\Users\\think\\Desktop\\Java作业4\\a.mp3";       

     String dest="C:\\Users\\think\\Desktop\\Java作业4\\b.mp3";    

     CopyFile(src,dest);       

     long end = System.currentTimeMillis();       

     System.out.print("花费的时间：" + (end - start));        }    

     private void CopyFile(String src, String dest) {   

  //使用缓冲流实现复制    

     BufferedInputStream bis = null;   

     BufferedInputStream bos = null;     try {    

  //提供读入写入文件      

     File file1 = new File(src);       

     File file2 = new File(dest);       

  //创建相应的节点流       

      FileInputStream fis = new FileInputStream(file1);       

      FileOutputStream fos =new FileOutputStream(file2);    

  //将创建的节点流的对象传递给缓冲就的构造器中       

      BufferedInputStream bis1 = new BufferedInputStream(fis);     

      BufferedOutputStream bos1 = new BufferedOutputStream(fos);   

  //具体的实现文件复制的操作      

      byte[] b = new byte[1024];

  //使用数组来实现传递，用1024个字节传递     

      int len;        

      while((len = bis1.read(b)) != -1){    

      bos1.write(b,0,len);                 

}    

       } catch (IOException e) {      

   // TODO Auto-generated catch block      

       e.printStackTrace();     }finally{    

   //关闭流    

           if(bos != null){          

           try {          

           bos.close();       

           } catch (IOException e) {         

    // TODO Auto-generated catch block         

           e.printStackTrace();     

    }      

    }  

       if(bis != null){            try {         

       bis.close();       

  } catch (IOException e) {       

    // TODO Auto-generated catch block      

        e.printStackTrace();       

           }      

           }

 }

 }

 }