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Java输入输出流复制文件所用时间对比

废话不多说,关键代码如下所述:

package com.edu.xynu; 
import java.io.BufferedInputStream; 
import java.io.BufferedOutputStream; 
import java.io.File; 
import java.io.FileInputStream; 
import java.io.FileOutputStream; 
import java.io.IOException; 
public class IOUnitCopy { 
//按字节 
public static void copyByByte(File srcFile,File destFile) throws IOException{ 
FileInputStream fis=new FileInputStream(srcFile); 
FileOutputStream fos=new FileOutputStream(destFile); 
int i; 
while((i=fis.read())!=-1){ 
fos.write(i); 
} 
fis.close(); 
fos.close(); 
} 
//按字节数组 
public static void copyByByteArray(File srcFile,File destFile) throws IOException{ 
FileInputStream fis=new FileInputStream(srcFile); 
FileOutputStream fos=new FileOutputStream(destFile); 
byte []buf=new byte[10*1024]; 
int i; 
while((i=fis.read(buf, 0, buf.length))!=-1){ 
fos.write(buf, 0, i); 
} 
fis.close(); 
fos.close(); 
} 
//字节缓冲流 
public static void copyByBuff(File srcFile,File destFile) throws IOException{ 
BufferedInputStream bis=new BufferedInputStream(new FileInputStream(srcFile)); 
BufferedOutputStream bos=new BufferedOutputStream(new FileOutputStream(destFile)); 
int i; 
while((i=bis.read())!=-1){ 
bos.write(i); 
} 
bos.flush(); 
bis.close(); 
bos.close(); 
} 
//字节数组批量读取 缓冲输出流写入 
public static void copyByBuffArray(File srcFile,File destFile) throws IOException{ 
FileInputStream bis=new FileInputStream(srcFile); 
BufferedOutputStream bos=new BufferedOutputStream(new FileOutputStream(destFile)); 
byte [] buf=new byte[10*1024]; 
int len; 
while((len=bis.read(buf,0,buf.length))!=-1){ 
bos.write(buf,0,len); 
} 
bos.flush(); 
bis.close(); 
bos.close(); 
} 
} 
package com.edu.xynu; 
import java.io.File; 
import java.io.IOException; 
public class IOUnitsCopyTest { 
public static void main(String[] args) { 
// TODO Auto-generated method stub 
try { 
long start=System.currentTimeMillis(); 
// IOUnitCopy.copyByByte(new File("c:\\1.mp3"), new File( 
// "c:\\2.mp3"));//90713ms 
// IOUnitCopy.copyByByteArray(new File("c:\\1.mp3"), new File( 
// "c:\\3.mp3"));//41ms 
// IOUnitCopy.copyByBuff(new File("c:\\1.mp3"), new File( 
// "c:\\4.mp3"));//556ms 
// IOUnitCopy.copyByByteArray(new File("c:\\1.mp3"), new File( 
// "c:\\5.mp3"));//30ms 
long end=System.currentTimeMillis(); 
System.out.println(end-start); 
} catch (IOException e) { 
// TODO Auto-generated catch block 
e.printStackTrace(); 
} 
} 
}

测试文件是

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