package com.crow;

import java.io.File;

import java.io.RandomAccessFile;

import java.nio.ByteBuffer;

import java.nio.CharBuffer;

import java.nio.MappedByteBuffer;

import java.nio.channels.FileChannel;

import java.nio.charset.Charset;

import java.nio.charset.CharsetDecoder;

import java.nio.charset.CharsetEncoder;

/**

* Created by CrowHawk on 17/9/4.

*/

public class UseCharsets {

public static void main(String[] args) throws Exception{

String inputFile = "ReadAndShow.txt";

String outputFile = "sampleout.txt";

long inputLength = new File( inputFile ).length();

RandomAccessFile inf = new RandomAccessFile( inputFile, "r" );

RandomAccessFile outf = new RandomAccessFile( outputFile, "rw" );

FileChannel infc = inf.getChannel();

FileChannel outfc = outf.getChannel();

MappedByteBuffer inputData = infc.map(FileChannel.MapMode.READ_ONLY, 0, inputLength);

Charset latin1 = Charset.forName( "ISO-8859-1" );

CharsetDecoder decoder = latin1.newDecoder();//解码器

CharsetEncoder encoder = latin1.newEncoder();//编码器

CharBuffer cb = decoder.decode( inputData );//将字节数据解码为一组字符

// Process char data here

ByteBuffer outputData = encoder.encode( cb );//要写回数据，我们必须使用 CharsetEncoder 将它转换回字节

outfc.write( outputData );

inf.close();

outf.close();

}

}