【Java BufferedReader和BufferedWriter】

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package com.yuzhenc.io;

import java.io.*;

/**
 * @author: yuzhenc
 * @date: 2022-04-04 22:27:58
 * @desc: com.yuzhenc.io
 * @version: 1.0
 */
public class Test08 {
    public static void main(String[] args) throws IOException {
        //创建对象映射到操作系统文件
        //目标文件
        File file = new File("d:\\tmp\\testcopy.sql");
        //源文件
        File file1 = new File("d:\\tmp\\test.sql");
        //方式1 缓冲数组
        //怼管子
        FileWriter fileWriter = new FileWriter(file);
        FileReader fileReader = new FileReader(file1);
        //缓冲数组
        char[] chars = new char[5];
        int len;
        long startTime = System.currentTimeMillis();
        while((len = fileReader.read(chars)) != -1) {
            String str = new String(chars,0,len);
            fileWriter.write(str);
        }
        long endTime = System.currentTimeMillis();
        //关闭流
        fileWriter.close();
        fileReader.close();

        //方式2 字符缓冲流（处理流）+字符数组
        //怼管子
        FileWriter fileWriter1 = new FileWriter(file);
        FileReader fileReader1 = new FileReader(file1);
        //在管子上怼管子
        BufferedWriter bufferedWriter = new BufferedWriter(fileWriter1);
        BufferedReader bufferedReader = new BufferedReader(fileReader1);
        //缓冲字符数组
        char[] chars1 = new char[5];
        long startTime1 = System.currentTimeMillis();
        while((len = bufferedReader.read(chars1)) != -1) {
            bufferedWriter.write(chars1,0,len);
        }
        long endTime1 = System.currentTimeMillis();
        //关闭流
        bufferedWriter.close();
        bufferedReader.close();
        fileWriter.close();
        fileReader.close();

        System.out.println("方式1耗时："+(endTime-startTime));//490
        System.out.println("方式2耗时："+(endTime1-startTime1));//177
    }
}