2026.6.1

学习下载MarkDown并熟练使用，再下载JDK，进行环境配置，最后下载idea安装包。
代码练习
1、

点击查看代码

import java.util.Scanner;
//TIP To <b>Run</b> code, press <shortcut actionId="Run"/> or
// click the <icon src="AllIcons.Actions.Execute"/> icon in the gutter.
public class Main {
    public static void main(String[] args) {
        //TIP Press <shortcut actionId="ShowIntentionActions"/> with your caret at the highlighted text
        // to see how IntelliJ IDEA suggests fixing it.
        Scanner sc=new Scanner(System.in);
        System.out.println("====欢迎来到微头条");
        System.out.println("请输入用户名");
        String s=sc.nextLine();
        System.out.println("欢迎你, "+s+"!");
        sc.close();


        for (int i = 1; i <= 5; i++) {
        //TIP Press <shortcut actionId="Debug"/> to start debugging your code. We have set one <icon src="AllIcons.Debugger.Db_set_breakpoint"/> breakpoint
            // for you, but you can always add more by pressing <shortcut actionId="ToggleLineBreakpoint"/>.
             System.out.println("i = " + i);
        }
    }
}

2、

点击查看代码

import java.util.Scanner;
import java.util.zip.Deflater;

public class a1 {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        while (true) {
            System.out.println("======微头条主菜单======");
            System.out.println("1,注册");
            System.out.println("2,登录");
            System.out.println("3,退出");
            System.out.print("请选择：");
            int choice = scanner.nextInt();
            scanner.nextLine();
            switch (choice) {
                case 1:
                    System.out.print("用户名：");
                    String regName = scanner.nextLine();
                    System.out.print("密码：");
                    String regPwd = scanner.nextLine();
                    System.out.println("注册成功！");
                    break;
                case 2:
                    System.out.print("用户名：");
                    String loginName = scanner.nextLine();
                    System.out.print("密码：");
                    String loginPwd = scanner.nextLine();
                    if ("admin".equals(loginName) && "123".equals(loginPwd)) {
                        System.out.println("登录成功！");
                    } else {
                        System.out.println("用户名或密码错误！");
                    }
                    break;
                case 3:
                    System.out.print("再见!");
                    scanner.close();
                    return;
                default:
                    System.out.println("无效选择：请重新输入！");
            }
        }
    }
}

3、

点击查看代码

import java.beans.JavaBean;
import java.util.Scanner;
public class a2 {
    static String[]newsTitles=new String[100];
    static int newsCount=0;
    static Scanner scanner=new Scanner(System.in);
    public static void main(String[] args) {
        newsTitles[newsCount++]= "Java 17 正式发布!";
        newsTitles[newsCount++]="微头条项目今日启动";
        while (true){
            System.out.println("\n======微头条主菜单======");
            System.out.println("1.注册");
            System.out.println("2.登录");
            System.out.println("3.查看新闻列表");
            System.out.println("4.发布新闻");
            System.out.println("5.退出");
            System.out.println("请选择：");
            int choice=scanner.nextInt();
            scanner.nextLine();
            switch(choice){
                case 1:
                    registar();
                    break;
                    case 2:
                        login();
                        break;
                        case 3:
                            showNewsList();
                            break;
                            case 4:
                                publishNews();
                                break;
                                case 5:
                                    System.out.println("再见！");
                                    scanner.close();
                                    return;
                default:
                    System.out.println("无效选择！");
            }
        }
    }
    static void registar() {
        System.out.println("注册成功！");
    }
    static void login() {
        System.out.println("用户名：");
        String name = scanner.nextLine();
        System.out.println("密码：");
        String pad = scanner.nextLine();
        if ("admin".equals(name)&&"123".equals(pad)) {
            System.out.println("登录成功！");
        }else{
            System.out.println("登录失败！");
        }
    }
    static void showNewsList(){
        System.out.println("\n======新闻列表======");
        if(newsCount==0){
            System.out.println("暂无新闻");
            return;
        }
        for(int i=0;i<newsCount;i++){
            System.out.println((i+1)+"."+newsTitles[i]);
        }
    }
    static void publishNews(){
        System.out.println("请输入新闻题目：");
        String title=scanner.nextLine();
        if (newsCount<newsTitles.length){
            newsTitles[newsCount++]=title;
            System.out.println("发布成功！");
        }else{
            System.out.println("新闻库已满，无法发布！");
        }
    }
}