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/**  
     * ÐÞ¸ÄÎļþÖеÄijһ²¿·ÖµÄÊý¾Ý²âÊÔ:½«×Ö¶¨Î»ÖõÄ×Öĸ¸ÄΪ´óд  
     * @param fName  :ÒªÐ޸ĵÄÎļþÃû×Ö  
     * @param start:Æðʼ×Ö½Ú  
     * @param len:ÒªÐ޸ĶàÉÙ¸ö×Ö½Ú  
     * @return :ÊÇ·ñÐ޸ijɹ¦  
     * @throws Exception:Îļþ¶ÁдÖпÉÄܳöµÄ´í  
* @author  javaFound  
     */  
    public static boolean changeFile(String fName,int start,int len) throws Exception{   
      //´´½¨Ò»¸öËæ»ú¶ÁдÎļþ¶ÔÏó   
        java.io.RandomAccessFile raf=new java.io.RandomAccessFile(fName,"rw");   
        long totalLen=raf.length();   
        System.out.println("Îļþ×ܳ¤×Ö½ÚÊÇ: "+totalLen);   
        //´ò¿ªÒ»¸öÎļþͨµÀ   
        java.nio.channels.FileChannel channel=raf.getChannel();   
        //Ó³ÉäÎļþÖеÄijһ²¿·ÖÊý¾ÝÒÔ¶Áдģʽµ½ÄÚ´æÖÐ   
        java.nio.MappedByteBuffer buffer=  channel.map(FileChannel.MapMode.READ_WRITE, start, len);   
        //ʾÀýÐÞ¸Ä×Ö½Ú   
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import java.util.*;
public class Dais02
{
 public static void main(String args[])
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 Scanner s = new Scanner(System.in);
 System.out.println("ÇëÊäÈëÄãÏëÒªÊÇÊý×Ö");
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