3-16自由编程题，请老师点评

package com.imooc.ByteStream;

import java.io.BufferedOutputStream;

import java.io.BufferedReader;

import java.io.BufferedWriter;

import java.io.FileNotFoundException;

import java.io.FileOutputStream;

import java.io.IOException;

import java.io.OutputStreamWriter;

import javax.imageio.IIOException;

public class ByteStreamTest {

public static void main(String[] args) {

// TODO Auto-generated method stub

try {

FileOutputStream fos=new FileOutputStream("one.txt");

OutputStreamWriter osw=new OutputStreamWriter(fos);

int n=0;

long start=System.currentTimeMillis();

for(int i=0;i<100000;i++)

osw.write((char) (1+Math.random()*99));

long end=System.currentTimeMillis();

long one=end-start;

System.out.println("one不使用缓冲流来写"+"\n"+"用时为："+one);

osw.close();

fos.close();

FileOutputStream fos1=new FileOutputStream("two.txt");

BufferedOutputStream bw=new BufferedOutputStream(fos1);

start=System.currentTimeMillis();

for(int i=0;i<100000;i++){

bw.write((char) (1+Math.random()*99));

}

bw.flush();

end=System.currentTimeMillis();

long two=end-start;

System.out.println("two使用缓冲流来写"+"\n"+"用时为："+(two));

System.out.println("用缓冲流来写节省了"+(one-two)+"ms");

fos1.close();

bw.close();

} catch (FileNotFoundException e) {

// TODO Auto-generated catch block

e.printStackTrace();

}catch (IOException e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

}

}

PS：append(true)如何理解使用？？