Java基础-IO流

package com.j2se.d59.demo;

import java.io.*;

//IO里的对象来自于java.io.*;
//IO流的输入输出是相对于内存RAM的
//分类：单位【字节流、字符流】or方向【输入流、输出流】or功能【节点流、处理流】
//所有的IO流由四个抽象类扩展而来：
//InputStream 的子类 FileInputStream BufferedInputStream
//OutputStream 的子类FileInputStream BufferedOutputStream
//Reader 的子类FileReader BufferedReader
//Writer 的子类FileWriter BufferedWriter
public class IOTest {

    public static void main(String[] args) {
        // TODO Auto-generated method stub
        // 以下代码用字节流和字符流2种方法完成文件复制功能
        // 1 准备
        String path1 = "D:\\Java\\Test\\红楼梦-曹雪芹.txt";
        String path2 = "D:\\Java\\Test\\程序创建：红楼梦-曹雪芹.txt";
        String path3 = "D:\\Java\\Test\\红楼梦-曹雪芹 - 副本.txt";
        String path4 = "D:\\Java\\Test\\程序创建：红楼梦-曹雪芹 - 副本.txt";
        byte[] b = new byte[1024 * 256];
        char[] c = new char[1024 * 256];
        // 2 声明
        FileInputStream fis = null;
        BufferedInputStream bis = null;
        FileOutputStream fos = null;
        BufferedOutputStream bos = null;
        FileReader fr = null;
        BufferedReader br = null;
        FileWriter fw = null;
        BufferedWriter bw = null;
        // 3 创建
        try {
            fis = new FileInputStream(path1);
            bis = new BufferedInputStream(fis);
            fos = new FileOutputStream(path2);
            bos = new BufferedOutputStream(fos);
            fr = new FileReader(path3);
            br = new BufferedReader(fr);
            fw = new FileWriter(path4);
            bw = new BufferedWriter(fw);
            // 4读取
            int ib = bis.read(b);
            // 5判断-方法1
            long t1 = System.currentTimeMillis();
            while (ib > 0) {
                // 6复制
                bos.write(b, 0, ib);
                // 7循环
                ib = bis.read(b);
            }
            // 8刷新
            bw.flush();
            long t2 = System.currentTimeMillis();
            System.out.println("使用字节流复制文件完成，用时：" + (t2 - t1) + "毫秒");
            long t3 = System.currentTimeMillis();
            int ic = br.read(c);
            // 判断-方法2
            while (ic > 0) {
                // 复制
                bw.write(c, 0, ic);
                // 循环
                ic = br.read(c);
            }
            // 刷新
            bw.flush();
            long t4 = System.currentTimeMillis();
            System.out.println("使用字符流复制文件完成，用时：" + (t4 - t3) + "毫秒");
            // =============以下全是异常处理代码段，可以不看=============
        } catch (FileNotFoundException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } finally {
            // 9 关闭
            if (bis != null) {
                try {
                    bis.close();
                } catch (IOException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                }
            }
            if (fis != null) {
                try {
                    fis.close();
                } catch (IOException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                }
            }
            if (bos != null) {
                try {
                    bos.close();
                } catch (IOException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                }
            }
            if (fis != null) {
                try {
                    fis.close();
                } catch (IOException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                }
            }
            if (br != null) {
                try {
                    br.close();
                } catch (IOException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                }
            }
            if (fr != null) {
                try {
                    fr.close();
                } catch (IOException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                }
            }
            if (bw != null) {
                try {
                    bw.close();
                } catch (IOException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                }
            }
            if (fw != null) {
                try {
                    fw.close();
                } catch (IOException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                }
            }
        }

    }

}