/* * This source file was generated by the Gradle 'init' task */package com.example.minitl;import java.util.*;
public class Main { public static void main(String[] args) {
Scanner sc = new Scanner(System.in); PostStore store = new PostStore();
while (true) { System.out.println("===== minitl cli ====="); System.out.println("1) post"); System.out.println("2) list"); System.out.println("3) like"); System.out.println("4) delete"); System.out.println("5) quit");
int choice = Integer.parseInt(sc.nextLine().trim());
try { switch (choice) { case 1 -> { System.out.print("---write author: "); String author = sc.nextLine();
System.out.print("---write body: "); String body = sc.nextLine();
Post p = store.add(author, body); System.out.println("created: " + p); } case 2 -> { for (Post p : store.list()) { System.out.println(p); } } case 3 -> { System.out.print("---choose id: "); long id = Long.parseLong(sc.nextLine()); store.like(id); System.out.println("liked!"); } case 4 -> { System.out.print("---choose id: "); long id = Long.parseLong(sc.nextLine()); store.delete(id); System.out.println("deleted!"); } case 5 -> { System.out.println("quited"); return; } default -> System.out.println("invalid"); } } catch (PostNotFoundException e) { System.out.println(e.getMessage()); } } }}
PostNotFoundExeption
package com.example.minitl;
public class PostNotFoundException extends RuntimeException { public PostNotFoundException(long id) { super("Post not found: " + id); }}
PostStore
package com.example.minitl;import java.util.*;
public class PostStore {
private final List<Post> posts = new ArrayList<>(); private long nextId = 1; //add(auther, body)->新しいpostをつくって先頭に追加し、返す public Post add(String author, String body) { Post p = new Post(nextId++, author, body, 0); posts.add(0, p); // 先頭に追加 return p; }
//list()ー＞全件を新しい順でかえす public List<Post> list() { return new ArrayList<>(posts); // コピー返す }
//like(id)->likeCountを+1した新しいpostに差し替える。なければ例外
public void like(long id) { for (int i = 0; i < posts.size(); i++) { Post p = posts.get(i); if (p.id() == id) { Post updated = new Post(p.id(), p.author(), p.body(), p.likeCount() + 1); posts.set(i, updated); return; } } throw new PostNotFoundException(id); }
// delete(id)->さくじょする。存在しなければ例外 public void delete(long id) { boolean removed = posts.removeIf(p -> p.id() == id); if (!removed) { throw new PostNotFoundException(id); } }}
Post
package com.example.minitl;
public record Post(long id, String author, String body, int likeCount) {}
build.gradle
tasks.named('run') { standardInput = System.in}