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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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