java对文件的操作

package FileIO;

import java.awt.image.BufferedImage;
import java.io.BufferedInputStream;
import java.io.BufferedReader;
import java.io.DataOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.FileReader;
import java.io.IOException;

public class OperateFile {

public static void main(String[] args) throws IOException {
File file  = new File("D:\\","test.txt");
File file2 = new File("D:\\","test2.txt");
    file.createNewFile();
    FileOutputStream outputstream = new FileOutputStream(file);
    DataOutputStream dataout = new DataOutputStream(outputstream);
    String str = "sssssssssssssssss";
    char ch = 0;
    byte [] b= str.getBytes();
    dataout.write(b);
   
    FileInputStream fileinputstream = new FileInputStream(file2);
//     byte [] contents = new byte[fileinputstream.available()];
//     for(int j=0;j<contents.length;j++)
//     {
//     outputstream.write(contents[j]);
//     }
   
    byte[] buffer = new byte[1024];  
        int length;  
        while ((length = fileinputstream.read(buffer)) > 0) {  
        outputstream.write(buffer, 0, length);  
        }  

   
    BufferedReader read = new BufferedReader(new FileReader("D:\\test2.txt"));
  
    String  data;
    while((data = read.readLine())!=null)
    {
    //System.out.println(data);
    }
   
    BufferedInputStream bufferinputstream = new BufferedInputStream(fileinputstream);
        byte[] bufferbyte = new byte[1024];
   
//     while(bufferinputstream.read(bufferbyte)!=-1)
//     {
//     outputstream.write(bufferbyte);
//     }

    outputstream.close();
    dataout.close();
    fileinputstream.close();
    read.close();

}
}