[edit] 図書一覧表示のエラー箇所を修正しました

src/main/java/com/example/demo/controller/BookController.java

@@ -1,13 +1,21 @@
 package com.example.demo.controller;
 
+import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.stereotype.Controller;
 import org.springframework.ui.Model;
 import org.springframework.web.bind.annotation.GetMapping;
 
+import com.example.demo.service.BookServiceImpl;
+
 @Controller
 public class BookController {
+	@Autowired
+	private BookServiceImpl bookService;
+	
 	@GetMapping("/book")
 	public String book(Model model) {
+		
+		// DBから取得したデータをHTMLで扱えるようにする
 		model.addAttribute("book",bookService.findAll());
 		return "book";
 	}

src/main/java/com/example/demo/entity/Book.java

@@ -15,7 +15,8 @@ import lombok.Data;
 @Data
 @Table(name = "book")
 public class Book {
-	//貸出処理で使用する図書ID
+	
+	//図書ID
 	@Id
 	@GeneratedValue(strategy = GenerationType.IDENTITY)
 	@Column(name = "book_Id", nullable = false)
@@ -46,7 +47,7 @@ public class Book {
 	private Date publicationDate;
 
 	// サブカテゴリーID
-	@Column(name = "subcategory_id", nullable = false)
+	@Column(name = "book_subcategory_id", nullable = false)
 	private Integer subcategoryId;
 
 	//	// カテゴリー名

src/main/java/com/example/demo/repository/BookRepository.java

@@ -1,9 +1,10 @@
 package com.example.demo.repository;
 
-import java.awt.print.Book;
 
 import org.springframework.data.jpa.repository.JpaRepository;
 
+import com.example.demo.entity.Book;
+
 public interface BookRepository extends JpaRepository<Book, Integer>{
 
 }

src/main/java/com/example/demo/service/BookService.java

@@ -7,5 +7,5 @@ import com.example.demo.entity.Book;
 public interface BookService {
 	String booklist(Book book);
 
-	List<Book> findAll();
+	List<java.awt.print.Book> findAll();
 }

src/main/java/com/example/demo/service/BookServiceImpl.java

@@ -1,6 +1,6 @@
 package com.example.demo.service;
 
-import java.awt.print.Book;
+
 import java.util.List;
 
 import org.springframework.beans.factory.annotation.Autowired;
@@ -10,24 +10,26 @@ import com.example.demo.entity.Book;
 import com.example.demo.repository.BookRepository;
 
 @Service
-public class BookServiceImpl implements BookService{
+public class BookServiceImpl{
 	
 	@Autowired
 	private BookRepository bookRepository;
 	
-	@Override
-	public String booklist(Book book) {
-		Book booklist = new Book();
-		booklist.set
-		return null;
-	}
+//	@Override
+//	public String booklist(com.example.demo.entity.Book book) {
+//		Book booklist = new Book();
+//		booklist.setBookId(book.getBookId());
+//		
+//		return null;
+//	}
+	
+	
 
-	@Override
 	public List<Book> findAll() {
-		// TODO 自動生成されたメソッド・スタブ
-		return null;
+		return bookRepository.findAll();
 	}
 
 	
 	
+
 }

src/main/resources/templates/book.html

@@ -1,5 +1,6 @@
 <!DOCTYPE html>
-<html>
+
+<html xmlns:th="http://www.thymeleaf.org">
 
 <head>
 	<meta charset="UTF-8">
@@ -7,8 +8,57 @@
 </head>
 
 <body>
+	<div class="container">
+		<h1>社内図書一覧</h1>
+		<div class="float-end">
+		</div>
 		<form method="get" action="bookLend">
 
+			<table class="table table-striped">
+				<thead>
+					<tr>
+						<th>図書ID</th>
+						<th>ISBN</th>
+						<th>書籍名</th>
+						<th>著者名</th>
+						<th>出版社</th>
+						<th>出版日</th>
+						<th>カテゴリー名</th>
+						<th>サブカテゴリー名</th>
+						<th>保管場所</th>
+						<th>貸出状態</th>
+						<th>本の状態</th>
+						<th>備考</th>
+						<th>登録日時</th>
+						<th>更新日時</th>
+						<th>寄贈者</th>
+						<th>寄贈者</th>
+						<th>操作</th>
+					</tr>
+				</thead>
+
+				<tbody>
+					<tr th:each="b : ${book}">
+						<td th:text="*{b.bookId}"></td>
+						<td th:text="*{b.bookManageId}"></td>
+						<td th:text="*{b.title}"></td>
+						<td th:text="*{b.isbn}"></td>
+						<td th:text="*{b.author}"></td>
+						<td th:text="*{b.publisher}"></td>
+						<td th:text="*{b.publicationDate}"></td>
+						<td th:text="*{b.subcategoryId}"></td>
+						<td th:text="*{b.locationId}"></td>
+						<td th:text="*{b.condition}"></td>
+						<td th:text="*{b.createdAt}"></td>
+						<td th:text="*{b.updatedAt}"></td>
+						<td th:text="*{b.isDeleted}"></td>
+						<td th:text="*{b.donorId}"></td>
+						<td th:text="*{b.description}"></td>
+						<td th:text="*{b.bookApproval}"></td>
+					</tr>
+				</tbody>
+			</table>
+
 
 			<button type="submit" class="btn-login">
 				<svg viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round"