java基础知识-18 文件IO流的操作

一  字节流的复制

1.1 字节流复制

1.代码

package com.ljf.spring.boot.demo.test;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;

/**
 * @ClassName: FileIo
 * @Description: TODO
 * @Author: admin
 * @Date: 2024/02/18 12:14:37 
 * @Version: V1.0
 **/
public class FileIo {
    public static void main(String[] args) {
        FileInputStream fileInputStream=null;
        FileOutputStream fileOutputStream=null;
        try {
            fileInputStream=new FileInputStream(new File("d:/liu.txt"));
            fileOutputStream=new FileOutputStream(new File("e:/liu.txt"));
            byte[] b=new byte[1024];
            int len=0;
            while((len=fileInputStream.read(b))!=-1){
                fileOutputStream.write(b,0,len);
            }
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            if(fileInputStream != null){
                try {
                    fileInputStream.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
            if(fileOutputStream != null){
                try {
                    fileOutputStream.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
    }
}

2.文件内容

3.复制后

1.2 字节流write方法

1.代码

     FileOutputStream fileOutputStream1= null;
        try {
            fileOutputStream1 = new FileOutputStream(new File("d:/liu.txt"));
            fileOutputStream1.write("abcd".getBytes());
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        }
      
       fileOutputStream1.close();
    }

2.书写内容