filelockexp.java

Java课堂练习

/**
 * @(#)FileLockExp.java
 *
 *
 * @author 
 * @version 1.00 2007/11/19
 */
import java.io.*;
import java.nio.*;
import java.nio.channels.*;

public class FileLockExp {
        
    /**
     * Creates a new instance of <code>FileLockExp</code>.
     */
    public FileLockExp() {
    }
    
    /**
     * @param args the command line arguments
     */
    public static void main(String[] args) {
        // TODO code application logic here
     int b;
     byte tom[]=new byte[12];
     try {
      RandomAccessFile  input=new RandomAccessFile("4.txt","rw");
      FileChannel  channel=input.getChannel();
      while ((b=input.read(tom,0,10))!=-1) {
        FileLock lock=channel.tryLock();
        String  s=new String(tom,0,b);
        System.out.println(s);
        try {
         Thread.sleep(1000);
         lock.release();
        }
        catch (Exception ee) {
         System.out.println(ee);
        }
      }
     }
     catch (Exception e) {
      System.out.println(e);
     }
    }
}