3（1）-字符缓冲流

package com.io;

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.File;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;

import org.junit.Test;

public class 缓冲字符流 {
    
    @Test
    public void bufferedReaderTest(){
        File file = new File("hello.txt");
        FileReader fr = null;
        BufferedReader br = null;
        try {
            fr = new FileReader(file);
            br = new BufferedReader(fr);
            /**
             * 使用旧的方法，读到一个char数组，不写了
             * 下面使用readline方法，最后一行返回null
             */
            String str;
            while((str = br.readLine()) != null){
                System.out.println(str);
            }
            
            
        }  catch (IOException e) {
            e.printStackTrace();
        }finally{
            try {
                br.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }
    
    @Test
    public void bufferedWriterTest(){

        File file = new File("hello.txt");
        File fileOut = new File("bf_reader.txt");
        FileReader fr = null;
        FileWriter fw = null;
        
        
        BufferedReader br = null;
        BufferedWriter bw = null;
        try {
            fr = new FileReader(file);
            br = new BufferedReader(fr);
            
            fw = new FileWriter(fileOut);
            bw = new BufferedWriter(fw);
            /**
             * 使用旧的方法，读到一个char数组，不写了
             * 下面使用readline方法，最后一行返回null
             */
            String str;
            while((str = br.readLine()) != null){
                bw.write(str);
                bw.newLine();//换行
                bw.flush();//flush
            }
            
            
        }   catch (IOException e) {
            e.printStackTrace();
        }finally{
            //先关输出流
            try {
                bw.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
            
            try {
                br.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    
    }
}