Java基础5

IO

案例：创建文件在里面写东西

package com.zhsj.mybatis.test;
import java.io.*;
import java.nio.charset.StandardCharsets;
import java.util.ArrayList;
import java.util.Scanner;
/**
 * @program: test
 * @description:
 * @author: liulq
 * @create: 2022-03-13 20:55
 */
public class Day2 {
    public static void main(String[] args) throws IOException {
     File targFile =createFile();
     writerFile(targFile);
        System.out.println("结束");
    }
    private static void writerFile(File targFile) throws IOException {
       try (
           FileOutputStream fileOutputStream = new FileOutputStream(targFile);
           OutputStreamWriter f = new OutputStreamWriter(fileOutputStream, StandardCharsets.UTF_8);
           PrintWriter pw = new PrintWriter(f);
       ){
           while (true){
               Scanner scanner = new Scanner(System.in);
               String line = scanner.nextLine().trim();
               System.out.println("输入的内容为"+line);
               if (line.trim().isBlank()){
                   System.out.println("输入结束");
                   break;
               }else {
                   pw.println(line);
                   pw.flush();
               }
           }
       }catch (IOException e) {
           e.printStackTrace();
       }
    }
    private static File createFile() throws IOException {
        System.out.println("输出文件名");
        Scanner scanner = new Scanner(System.in);
        String fileName =scanner.nextLine().trim();
        File f= new File("."+File.separator+fileName+".txt");
        if (f.isFile()){
            System.out.println("目录文件存在，删除"+f.delete());
        }
        System.out.println(f.createNewFile());
        return f;
    }
}

网络通讯

线程

concurrent