java基础回顾之 流（BufferedReader/BufferedWriter ）字符缓冲流, 默认有8192个字符的缓冲区

package com.bjpowernode.demo03;

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.FilterWriter;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.Reader;
import java.io.Writer;

/**
 * BufferedReader/BufferedWriter
 * 	字符缓冲流, 默认有8192个字符的缓冲区
 * @author Administrator
 *
 */
public class Test04 {

	public static void main(String[] args) throws IOException {
//		readData(); 		//使用字符缓冲流读取文件内容
		
//		readDataFromKeyboard(); 	//有人也使用字符缓冲流从键盘上读取数据
		
		writeData();
		
	}

	private static void writeData() throws IOException {
		Writer out = new FileWriter("d:/out.txt");
		BufferedWriter bWriter = new BufferedWriter(out);
		
		bWriter.write("一次写一行");
		bWriter.newLine(); 			//换行 
		bWriter.write("这是第二行");
		
		bWriter.flush();
		bWriter.close();
	}

	private static void readDataFromKeyboard() throws IOException {
		//把键盘字节流转换为字符流
		Reader in  = new InputStreamReader(System.in);
		//对字符流进行缓冲
		BufferedReader br = new BufferedReader(in);
		
		FileWriter fw = new FileWriter("d:/key.txt");
		
		String line = br.readLine();
		while( line.length() > 0 ){
//		while( line != null  ){
			System.out.println( line);
			fw.write(line);
			fw.write("\r\n");
			line = br.readLine();
		}
		
		br.close();
		fw.close();
	}

	private static void readData() throws IOException {
		//读取d:/test01.java文件, 该文件采用UTF-8编码
//		Reader in = new FileReader("d:/test01.java");
		//读取d:/out.txt文件,该文件采用GBK编码, 当前环境使用UTF-8
		Reader in = new InputStreamReader(new FileInputStream("d:/out.txt"), "GBK");
	
		BufferedReader br = new BufferedReader(in);
		
		//一次读取一行, 读到文件末尾返回null
		String line = br.readLine();
		while( line != null ){
			System.out.println( line );
			line = br.readLine();
		}
		
		br.close();
	}

}