hw3-2

src/main/java/com/example/springhw32/controller/CommentController.java

@@ -1,5 +1,28 @@
 package com.example.springhw32.controller;
 
+import com.example.springhw32.dto.CommentDto;
+import com.example.springhw32.service.CommentService;
+import lombok.RequiredArgsConstructor;
+import org.springframework.web.bind.annotation.*;
+
+import java.util.List;
+
+@RestController
+@RequiredArgsConstructor
+@RequestMapping("/posts")
 public class CommentController {
 
+    private final CommentService commentService;
+
+    // 댓글 작성
+    @PostMapping("/comments")
+    public CommentDto addComment(@ModelAttribute CommentDto commentDto, @RequestParam Long postId) {
+        return commentService.addComment(commentDto, postId);
+    }
+
+    // 특정 게시물에 달린 모든 댓글 조회
+    @GetMapping("/comments/{postId}")
+    public List<CommentDto> getAllComments(@PathVariable Long postId) {
+        return commentService.getAllComments(postId);
+    }
 }

src/main/java/com/example/springhw32/controller/PostController.java

@@ -1,5 +1,40 @@
 package com.example.springhw32.controller;
 
+import com.example.springhw32.dto.PostDto;
+import com.example.springhw32.service.PostService;
+import lombok.RequiredArgsConstructor;
+import org.springframework.web.bind.annotation.*;
+
+import java.util.List;
+
+@RestController
+@RequiredArgsConstructor
+@RequestMapping("/posts")
 public class PostController {
 
+    private final PostService postService;
+
+    // 글 등록
+    @PostMapping
+    public PostDto createPost(@ModelAttribute PostDto postDto, Long userId) {
+        return postService.createPost(postDto, userId);
+    }
+
+    // 최신순으로 글 조회
+    @GetMapping
+    public List<PostDto> findAllPostsByOrderByPostedAtDesc() {
+        return postService.findAllPostsByOrderByPostedAtDesc();
+    }
+
+    // 작성자 글 조회
+    @GetMapping("/{writer}")
+    public List<PostDto> findAllPostsByWriter(@PathVariable("writer") Long userId) {
+        return postService.findAllPostsByUserId(userId);
+    }
+
+    // 댓글 많은 순으로 글 조회
+    @GetMapping("/comments")
+    public List<PostDto> findAllPostsByOrderByCommentCountDesc() {
+        return postService.findAllPostsByOrderByCommentCountDesc();
+    }
 }

src/main/java/com/example/springhw32/controller/UserController.java

@@ -1,5 +1,21 @@
 package com.example.springhw32.controller;
 
+import com.example.springhw32.dto.UserDto;
+import com.example.springhw32.service.UserService;
+import lombok.RequiredArgsConstructor;
+import org.springframework.web.bind.annotation.ModelAttribute;
+import org.springframework.web.bind.annotation.PostMapping;
+import org.springframework.web.bind.annotation.RestController;
+
+@RestController
+@RequiredArgsConstructor
 public class UserController {
 
+    private final UserService userService;
+
+    // 회원 가입
+    @PostMapping("/users")
+    public UserDto join(@ModelAttribute UserDto userDto) {
+        return userService.join(userDto);
+    }
 }

src/main/java/com/example/springhw32/dto/CommentDto.java

@@ -1,5 +1,12 @@
 package com.example.springhw32.dto;
 
+import lombok.Getter;
+import lombok.Setter;
+
+@Getter
+@Setter
 public class CommentDto {
 
+    private String comment;
+
 }

src/main/java/com/example/springhw32/dto/PostDto.java

@@ -1,5 +1,18 @@
 package com.example.springhw32.dto;
 
+import lombok.Getter;
+import lombok.Setter;
+
+import java.time.LocalDateTime;
+
+@Getter
+@Setter
 public class PostDto {
 
+    private String title;
+
+    private String content;
+
+    private int commentCount;
+
 }

src/main/java/com/example/springhw32/dto/UserDto.java

@@ -1,5 +1,14 @@
 package com.example.springhw32.dto;
 
+import lombok.Getter;
+import lombok.Setter;
+
+@Getter
+@Setter
 public class UserDto {
 
+    private String username;
+
+    private String password;
+
 }

src/main/java/com/example/springhw32/entity/Comment.java

@@ -1,5 +1,22 @@
 package com.example.springhw32.entity;
 
+import jakarta.persistence.*;
+import lombok.Getter;
+import lombok.Setter;
+
+@Entity
+@Getter
+@Setter
 public class Comment {
 
+    @Id
+    @GeneratedValue(strategy = GenerationType.AUTO)
+    private long id;
+
+    @ManyToOne
+    private Post post;
+
+    @Column(nullable = false)
+    private String comment;
+
 }

src/main/java/com/example/springhw32/entity/Post.java

@@ -1,5 +1,31 @@
 package com.example.springhw32.entity;
 
+import jakarta.persistence.*;
+import lombok.Getter;
+import lombok.Setter;
+
+import java.time.LocalDateTime;
+
+@Entity
+@Getter
+@Setter
 public class Post {
 
+    @Id
+    @GeneratedValue(strategy = GenerationType.AUTO)
+    private Long id;
+
+    @ManyToOne
+    private User user;
+
+    @Column(nullable = false)
+    private String title;
+
+    @Column(nullable = false)
+    private String content;
+
+    private int commentCount;
+
+    private LocalDateTime postedAt;
+
 }

src/main/java/com/example/springhw32/entity/User.java

@@ -1,5 +1,22 @@
 package com.example.springhw32.entity;
 
+import jakarta.persistence.*;
+import lombok.Getter;
+import lombok.Setter;
+
+@Entity
+@Getter
+@Setter
 public class User {
 
+    @Id
+    @GeneratedValue(strategy = GenerationType.AUTO)
+    private Long id;
+
+    @Column(nullable = false)
+    private String username;
+
+    @Column(nullable = false)
+    private String password;
+
 }

src/main/java/com/example/springhw32/repository/CommentRepository.java

@@ -1,5 +1,12 @@
 package com.example.springhw32.repository;
 
-public interface CommentRepository {
+import com.example.springhw32.dto.CommentDto;
+import com.example.springhw32.entity.Comment;
+import org.springframework.data.jpa.repository.JpaRepository;
 
+import java.util.List;
+
+public interface CommentRepository extends JpaRepository<Comment, Long> {
+
+    List<Comment> findAllByPostId(Long postId);
 }

src/main/java/com/example/springhw32/repository/PostRepository.java

@@ -1,5 +1,16 @@
 package com.example.springhw32.repository;
 
-public interface PostRepository {
+import com.example.springhw32.dto.PostDto;
+import com.example.springhw32.entity.Post;
+import org.springframework.data.jpa.repository.JpaRepository;
 
+import java.util.List;
+
+public interface PostRepository extends JpaRepository<Post, Long> {
+
+    List<Post> findAllByOrderByPostedAtDesc();
+
+    List<Post> findAllByUserId(Long userId);
+
+    List<Post> findAllByOrderByCommentCountDesc();
 }

src/main/java/com/example/springhw32/repository/UserRepository.java

@@ -1,5 +1,8 @@
 package com.example.springhw32.repository;
 
-public interface UserRepository {
+import com.example.springhw32.entity.User;
+import org.springframework.data.jpa.repository.JpaRepository;
+
+public interface UserRepository extends JpaRepository<User, Long> {
 
 }

src/main/java/com/example/springhw32/service/CommentService.java

@@ -1,5 +1,51 @@
 package com.example.springhw32.service;
 
+import com.example.springhw32.dto.CommentDto;
+import com.example.springhw32.dto.PostDto;
+import com.example.springhw32.entity.Comment;
+import com.example.springhw32.entity.Post;
+import com.example.springhw32.repository.CommentRepository;
+import com.example.springhw32.repository.PostRepository;
+import lombok.RequiredArgsConstructor;
+import org.springframework.stereotype.Service;
+
+import java.util.Collection;
+import java.util.List;
+import java.util.stream.Collectors;
+
+@Service
+@RequiredArgsConstructor
 public class CommentService {
 
+    private final CommentRepository commentRepository;
+    private final PostRepository postRepository;
+
+    // 댓글 작성
+    public CommentDto addComment(CommentDto commentDto, Long postId) {
+        Post post = postRepository.findById(postId).orElseThrow(NullPointerException::new);
+
+        Comment comment = new Comment();
+        comment.setComment(commentDto.getComment());
+        comment.setPost(post);
+        commentRepository.save(comment);
+
+        post.setCommentCount(post.getCommentCount() + 1);
+        postRepository.save(post);
+
+        return commentDto;
+    }
+
+    // 특정 게시글에 작성된 댓글 조회
+    public List<CommentDto> getAllComments(Long postId) {
+        return commentRepository.findAllByPostId(postId).stream()
+                .map(this::convertToDto)
+                .collect(Collectors.toList());
+    }
+
+    // Entity -> Dto
+    private CommentDto convertToDto(Comment comment) {
+        CommentDto commentDto = new CommentDto();
+        commentDto.setComment(comment.getComment());
+        return commentDto;
+    }
 }

src/main/java/com/example/springhw32/service/PostService.java

@@ -1,5 +1,66 @@
 package com.example.springhw32.service;
 
+import com.example.springhw32.dto.PostDto;
+import com.example.springhw32.entity.Post;
+import com.example.springhw32.entity.User;
+import com.example.springhw32.repository.PostRepository;
+import com.example.springhw32.repository.UserRepository;
+import lombok.RequiredArgsConstructor;
+import org.springframework.stereotype.Service;
+
+import java.time.LocalDateTime;
+import java.util.List;
+import java.util.stream.Collectors;
+
+@Service
+@RequiredArgsConstructor
 public class PostService {
 
+    private final PostRepository postRepository;
+    private final UserRepository userRepository;
+
+    // 글 작성
+    public PostDto createPost(PostDto postDto, Long userId) {
+        User user = userRepository.findById(userId).orElseThrow(NullPointerException::new);
+
+        Post post = new Post();
+        post.setTitle(postDto.getTitle());
+        post.setContent(postDto.getContent());
+        post.setCommentCount(0);
+        post.setPostedAt(LocalDateTime.now());
+        post.setUser(user);
+        postRepository.save(post);
+
+        return postDto;
+    }
+
+    // 최신순으로 글 조회
+    public List<PostDto> findAllPostsByOrderByPostedAtDesc() {
+        return postRepository.findAllByOrderByPostedAtDesc().stream()
+                .map(this::convertToDto)
+                .collect(Collectors.toList());
+    }
+
+    // 특정 회원이 작성한 글 조회
+    public List<PostDto> findAllPostsByUserId(Long userId) {
+        return postRepository.findAllByUserId(userId).stream()
+                .map(this::convertToDto)
+                .collect(Collectors.toList());
+    }
+
+    // 댓글 많은 순으로 정렬 조회
+    public List<PostDto> findAllPostsByOrderByCommentCountDesc() {
+        return postRepository.findAllByOrderByCommentCountDesc().stream()
+                .map(this::convertToDto)
+                .collect(Collectors.toList());
+    }
+
+    // Entity -> Dto
+    private PostDto convertToDto(Post post) {
+        PostDto postDto = new PostDto();
+        postDto.setTitle(post.getTitle());
+        postDto.setContent(post.getContent());
+        postDto.setCommentCount(post.getCommentCount());
+        return postDto;
+    }
 }