使用转换流改变文件编码

package cn.tedu.io;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;

//转换文件编码，并且替换原文件
public class InputStreamReaderDemo {
public static void main(String[] args) throws IOException {

File file = new File("D:\\字符转字节.txt");

File tmp = new File("D:\\tmp.txt");

//将字节转为字符流
//读进来的是字节，但是展现的是字符
InputStreamReader isr = new InputStreamReader(new FileInputStream(file));
OutputStreamWriter osw = new OutputStreamWriter(new FileOutputStream(tmp),"utf-8");

//System.out.println(isr.getEncoding());

char[] cs = new char[1024];
int i = -1;
while((i=isr.read(cs))!=-1){
osw.write(cs, 0, i);
}

isr.close();
osw.close();

file.delete();

tmp.renameTo(file);

}

}