ÀûÓÃjavaÄÚ´æÓ³ÉäÎļþ»úÖÆʵÏÖCRCÑ­»·ÈßÓàУÑé

import java.nio.MappedByteBuffer;   
import java.nio.channels.FileChannel;   
import java.util.zip.CRC32;   
public static void main(String[] args){   
            try {                               //¶Ô
import java.nio.MappedByteBuffer;  
import java.nio.channels.FileChannel;  
import java.util.zip.CRC32;  
public static void main(String[] args){  
            try {                               //¶ÔÎļþ½øÐÐcrcУÑé  
            long begin = System.currentTimeMillis();  
            FileInputStream in = new FileInputStream("code.py");//Ö¸¶¨Ä¿±êÎļþ  
            FileChannel channel = in.getChannel(); //´ÓÎļþÖлñÈ¡Ò»¸öͨµÀ  
            CRC32 crc = new CRC32();  
            int length = (int)channel.size();  
            MappedByteBuffer buffer = channel.map(FileChannel.MapMode.READ_ONLY, 0, length); //ÓÃÖ»¶Áģʽ´Ó¸ÃͨµÀ»ñÈ¡×Ö½Ú»º³å£¬ÊµÏÖÎļþµ½ÄÚ´æµÄÓ³Éä  
            for(int i = 0;i<length;i++)