[hiro & bongf] Mission6 페이지나누기

src/main/java/com/codessquad/qna/web/QuestionPage.java

@@ -0,0 +1,65 @@
+package com.codessquad.qna.web;
+
+import com.codessquad.qna.web.domain.Question;
+import org.springframework.data.domain.Page;
+import org.springframework.data.domain.Pageable;
+
+import java.util.ArrayList;
+import java.util.List;
+
+public class QuestionPage {
+    private final int COUNT_NUMBERS_TO_SHOW = 5;
+    private final Pageable pageable;
+    private int previous;
+    private int next;
+    private Page<Question> questions;
+    private List<Integer> pageNumbers = new ArrayList<>(COUNT_NUMBERS_TO_SHOW);
+
+    public QuestionPage(Pageable pageable, Page<Question> questionsByPage) {
+        this.pageable = pageable;
+        this.questions = questionsByPage;
+        this.previous = questionsByPage.previousOrFirstPageable().getPageNumber();
+        if (questionsByPage.hasNext()) {
+            this.next = questionsByPage.nextPageable().getPageNumber();
+        } else {
+            this.next = questionsByPage.getNumber();
+
+        }
+        this.pageNumbers = createPageNumbers();
+    }
+
+    private List<Integer> createPageNumbers() {
+        int currentPage = questions.getNumber();
+        int totalPages = questions.getTotalPages();
+        int startNumber = (currentPage / COUNT_NUMBERS_TO_SHOW) * COUNT_NUMBERS_TO_SHOW;
+        int endNumber = startNumber + COUNT_NUMBERS_TO_SHOW - 1;
+
+        for (int i = startNumber; i <= endNumber; i++) {
+            pageNumbers.add(i);
+            if (i == totalPages - 1) {
+                break;
+            }
+        }
+        return pageNumbers;
+    }
+
+    public Pageable getPageable() {
+        return pageable;
+    }
+
+    public int getPrevious() {
+        return previous;
+    }
+
+    public int getNext() {
+        return next;
+    }
+
+    public Page<Question> getQuestions() {
+        return questions;
+    }
+
+    public List<Integer> getPageNumbers() {
+        return pageNumbers;
+    }
+}

src/main/java/com/codessquad/qna/web/controller/ApiAnswerController.java

@@ -23,7 +23,7 @@ public ApiAnswerController(AnswerService answerService) {
 
     @PostMapping
     public Answer createAnswer(@PathVariable long questionId, String contents, HttpSession session) {
-        User user = HttpSessionUtils.getSessionedUser(session).orElseThrow(NotLoginException::new);
+         User user = HttpSessionUtils.getSessionedUser(session).orElseThrow(NotLoginException::new);
         return answerService.postAnswer(user, questionId, contents);
     }
 
@@ -35,17 +35,17 @@ public Result deleteAnswer(@PathVariable("questionId") long questionId, @PathVar
     }
 
     @ExceptionHandler(IllegalEntityIdException.class)
-    public String handleIllegalEntityIdException(IllegalEntityIdException e) {
-        return e.getMessage();
+    public String handleIllegalEntityIdException() {
+        return "유효하지 않은 접근입니다";
     }
 
     @ExceptionHandler(NotLoginException.class)
-    public String handleNotLoginException(NotLoginException e) {
-        return e.getMessage();
+    public String handleNotLoginException() {
+        return "로그인이 필요합니다";
     }
 
     @ExceptionHandler(IllegalAccessException.class)
-    public String handleIllegalAccessException(IllegalAccessException e) {
-        return e.getMessage();
+    public String handleIllegalAccessException() {
+        return "자신의 답변만 삭제할 수 있습니다";
     }
 }

src/main/java/com/codessquad/qna/web/controller/QuestionController.java

@@ -1,10 +1,14 @@
 package com.codessquad.qna.web.controller;
 
 import com.codessquad.qna.web.HttpSessionUtils;
+import com.codessquad.qna.web.QuestionPage;
 import com.codessquad.qna.web.domain.Question;
 import com.codessquad.qna.web.domain.User;
 import com.codessquad.qna.web.exception.NotLoginException;
 import com.codessquad.qna.web.service.QuestionService;
+import org.springframework.data.domain.Pageable;
+import org.springframework.data.domain.Sort;
+import org.springframework.data.web.PageableDefault;
 import org.springframework.stereotype.Controller;
 import org.springframework.ui.Model;
 import org.springframework.web.bind.annotation.*;
@@ -36,8 +40,9 @@ public String createQuestion(Question question, HttpSession session) {
     }
 
     @GetMapping
-    public String getQuestions(Model model) {
-        model.addAttribute("questions", questionService.findQuestions());
+    public String getQuestions(@PageableDefault(size = 15, sort = "createdDateTime", direction = Sort.Direction.DESC) Pageable pageable, Model model) {
+        QuestionPage questionPages = questionService.getQuestionPage(pageable);
+        model.addAttribute("pages",  questionPages);
         return "/index";
     }
 

src/main/java/com/codessquad/qna/web/domain/AbstractEntity.java

@@ -12,7 +12,7 @@
 @MappedSuperclass
 @EntityListeners(AuditingEntityListener.class)
 public class AbstractEntity {
-    private static final DateTimeFormatter QUESTION_DATETIME_FORMAT = DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm");
+    private static final DateTimeFormatter DATETIME_FORMAT = DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm");
 
     @Id
     @GeneratedValue(strategy = GenerationType.IDENTITY)
@@ -57,7 +57,7 @@ private String getFormattedDate(LocalDateTime dateTime) {
         if (dateTime == null) {
             return "";
         }
-        return dateTime.format(QUESTION_DATETIME_FORMAT);
+        return dateTime.format(DATETIME_FORMAT);
     }
 }
 

src/main/java/com/codessquad/qna/web/repository/QuestionRepository.java

@@ -1,7 +1,10 @@
 package com.codessquad.qna.web.repository;
 
 import com.codessquad.qna.web.domain.Question;
-import org.springframework.data.repository.CrudRepository;
+import org.springframework.data.domain.Page;
+import org.springframework.data.domain.Pageable;
+import org.springframework.data.jpa.repository.JpaRepository;
 
-public interface QuestionRepository extends CrudRepository<Question, Long> {
+public interface QuestionRepository extends JpaRepository<Question, Long> {
+    Page<Question> findAll(Pageable pageable);
 }

src/main/java/com/codessquad/qna/web/service/QuestionService.java

@@ -1,11 +1,13 @@
 package com.codessquad.qna.web.service;
 
-import com.codessquad.qna.web.HttpSessionUtils;
+import com.codessquad.qna.web.QuestionPage;
 import com.codessquad.qna.web.domain.Question;
 import com.codessquad.qna.web.domain.User;
 import com.codessquad.qna.web.exception.IllegalAccessException;
 import com.codessquad.qna.web.exception.IllegalEntityIdException;
 import com.codessquad.qna.web.repository.QuestionRepository;
+import org.springframework.data.domain.Page;
+import org.springframework.data.domain.Pageable;
 import org.springframework.stereotype.Service;
 
 @Service
@@ -21,10 +23,6 @@ public void postQuestion(Question question, User user) {
         questionRepository.save(question);
     }
 
-    public Iterable<Question> findQuestions() {
-        return questionRepository.findAll();
-    }
-
     public Question findQuestion(long id) {
         return questionRepository
                 .findById(id)
@@ -53,4 +51,14 @@ private void checkSameWriter(Question question, User user) {
             throw new IllegalAccessException();
         }
     }
+
+    public Page<Question> getQuestionsByPage(Pageable pageable) {
+        return questionRepository.findAll(pageable);
+    }
+
+    public QuestionPage getQuestionPage(Pageable pageable) {
+        return new QuestionPage(pageable, getQuestionsByPage(pageable));
+    }
+
+
 }

src/main/java/temp.java

@@ -0,0 +1,10 @@
+public class temp {
+    public static void main(String[] args) {
+        for(int i=1; i<=200; i++) {
+            System.out.println(
+                    "INSERT INTO QUESTION (ID, WRITER_ID, TITLE, CONTENTS, CREATED_DATE_TIME, COUNT_OF_ANSWERS) VALUES ('"+ i + "', '1', '6', 'dui', '2021-03-20 16:03:03.106461', '1')"
+            );
+        }
+
+    }
+}