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package test;

import java.io.File;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.RandomAccessFile;


public class RandomAccessFileDemo{
	public static void main(String args[]) throws IOException{
		File f = new File("d:"+File.separator+"text.txt") ;		// 实例化File类的对象
		RandomAccessFile raf=new RandomAccessFile(f,"rw");
		raf.writeBytes("zhangsan");
		raf.close();
		read();
	}
	
	public static void read() throws IOException{
		File f = new File("d:"+File.separator+"text.txt") ;		// 实例化File类的对象
		RandomAccessFile raf=new RandomAccessFile(f,"r");
		byte b1=raf.readByte();
		System.out.println("b:"+b1);
		raf.skipBytes(5);
		byte b2=raf.readByte();
		System.out.println("b:"+b2);
		raf.seek(3);
		byte b3=raf.readByte();
		System.out.println("b:"+b3);
		System.out.println("b:"+(new String(new byte[]{b1,b2,b3})));
		raf.close();
	}
};
/**
b:122
b:97
b:110
b:zan
**/

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