i/o StringBuffer输入输出流

package com.xuexi.IO;

import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;

public class StringBufferTest {

    public static void main(String[] args) {
        StringBuffer sb3;
        File file = null;
        FileInputStream fis= null;
        FileOutputStream fos = null;
        BufferedInputStream bis = null;
        BufferedOutputStream bos = null;
        try{
            file = new File("d:\\20156.txt");
            fis = new FileInputStream(file);//创建文件输入
            bis = new BufferedInputStream(fis);
            bos = new BufferedOutputStream(
                        new FileOutputStream("e:\\20156.txt"));//i/o链和上面功能相同
            int i=0;
            sb3 = new  StringBuffer();
            while((i=fis.read())!=-1){//返回-1表示文件读取完毕
                char ch =(char)i;
                sb3.append(ch);
            }
            System.out.println(sb3.toString());
            bos.write(sb3.toString().getBytes());//缓存满一次性写出
        }catch(IOException e){
            e.printStackTrace();
        }finally{
            try {
                bos.flush();
                bos.close();
                bis.close();
            } catch (IOException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }

            }
}
}