Java文件复制
package day02;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
public class CopyTest2 {
public static void main(String[] args) {
File file= new File("demo/copy2.txt");
try {
FileInputStream in =new FileInputStream(file);
FileOutputStream out =new FileOutputStream("demo/copy3.txt");
byte [] b =new byte[1024];
long startTime =System.currentTimeMillis();
int len =-1;
while((len=in.read(b))!=-1) {
out.write(b,0,len);
}
System.out.println("复制完毕");
in.close();
out.close();
long endTime =System.currentTimeMillis();
System.out.println("消耗的时间:"+(endTime-startTime));
} catch (IOException e) {
e.printStackTrace();
}
}
}