Bootstrap和Java分页实例第二篇
在上一篇文章中，我们介绍了如何使用Bootstrap和Spring Boot实现基本的分页功能，本文将进一步探讨如何优化和扩展这些功能，以满足更复杂的需求。
环境准备
确保你已经安装了以下工具和库：
JDK 8或更高版本
Maven 3.2+
Spring Boot 2.3+
Thymeleaf
Bootstrap 4.3+
H2数据库（或其他任何关系型数据库）
项目结构
假设你的项目结构如下：
src/main/java/com/example/pagination
|-PaginationApplication.java
|-controller
| |-PaginationController.java
|-service
| |-PaginationService.java
| `-PaginationServiceImpl.java
|-repository
| `-UserRepository.java
`-model
`-User.java
1. 配置数据源
在application.properties文件中配置H2数据库：
spring.datasource.url=jdbc:h2:mem:testdb spring.datasource.driverClassName=org.h2.Driver spring.datasource.username=sa spring.datasource.password=password spring.jpa.database-platform=org.hibernate.dialect.H2Dialect spring.h2.console.enabled=true
2. 创建实体类
在model包下创建User.java：
package com.example.pagination.model;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
@Entity
public class User {
@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
private Long id;
private String name;
private int age;
// Getters and Setters
}
3. 创建仓库接口
在repository包下创建UserRepository.java：
package com.example.pagination.repository;
import com.example.pagination.model.User;
import org.springframework.data.jpa.repository.JpaRepository;
import org.springframework.stereotype.Repository;
@Repository
public interface UserRepository extends JpaRepository<User, Long> {
}
4. 创建服务层
在service包下创建PaginationService.java和PaginationServiceImpl.java：
package com.example.pagination.service;
import com.example.pagination.model.User;
import org.springframework.data.domain.Page;
import org.springframework.data.domain.Pageable;
public interface PaginationService {
Page<User> getUsers(Pageable pageable);
}
package com.example.pagination.service;
import com.example.pagination.model.User;
import com.example.pagination.repository.UserRepository;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.domain.Page;
import org.springframework.data.domain.Pageable;
import org.springframework.stereotype.Service;
@Service
public class PaginationServiceImpl implements PaginationService {
@Autowired
private UserRepository userRepository;
@Override
public Page<User> getUsers(Pageable pageable) {
return userRepository.findAll(pageable);
}
}
5. 创建控制器
在controller包下创建PaginationController.java：
package com.example.pagination.controller;
import com.example.pagination.model.User;
import com.example.pagination.service.PaginationService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.domain.Page;
import org.springframework.data.domain.PageRequest;
import org.springframework.data.domain.Pageable;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestParam;
@Controller
public class PaginationController {
@Autowired
private PaginationService paginationService;
@GetMapping("/users")
public String getUsers(@RequestParam(defaultValue = "0") int page, @RequestParam(defaultValue = "5") int size, Model model) {
Pageable pageable = PageRequest.of(page, size);
Page<User> users = paginationService.getUsers(pageable);
model.addAttribute("users", users);
model.addAttribute("currentPage", page);
model.addAttribute("totalPages", users.getTotalPages());
return "users";
}
}
6. 创建视图模板
在src/main/resources/templates目录下创建users.html：
<!DOCTYPE html>
<html lang="en" xmlns:th="http://www.thymeleaf.org">
<head>
<meta charset="UTF-8">
<title>Users</title>
<link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.3.1/css/bootstrap.min.css">
</head>
<body>
<div class="container">
<h1>Users List</h1>
<table class="table table-bordered">
<thead>
<tr>
<th>ID</th>
<th>Name</th>
<th>Age</th>
</tr>
</thead>
<tbody>
<tr th:each="user : ${users}">
<td th:text="${user.id}"></td>
<td th:text="${user.name}"></td>
<td th:text="${user.age}"></td>
</tr>
</tbody>
</table>
<nav aria-label="Page navigation">
<ul class="pagination">
<li class="page-item" th:classappend="${#numbers.sequence(1, currentPage 1)} ? 'disabled' : ''"><a class="page-link" th:href="@{/users(page=${currentPage 1}, size=${size})}">«</a></li>
<li class="page-item" th:each="i : ${#numbers.sequence(1, totalPages)}"><a class="page-link" th:href="@{/users(page=${i 1}, size=${size})}" th:text="${i}"></a></li>
<li class="page-item" th:classappend="${#numbers.sequence(currentPage + 1, totalPages)} ? 'disabled' : ''"><a class="page-link" th:href="@{/users(page=${currentPage + 1}, size=${size})}">»</a></li>
</ul>
</nav>
</div>
<script src="https://code.jquery.com/jquery-3.3.1.slim.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.14.7/umd/popper.min.js"></script>
<script src="https://stackpath.bootstrapcdn.com/bootstrap/4.3.1/js/bootstrap.min.js"></script>
</body>
</html>
7. 运行应用程序
启动Spring Boot应用程序，访问http://localhost:8080/users，你应该能看到分页的用户列表，你可以通过点击分页导航来切换不同的页面。
相关问题与解答栏目
问题1：如何自定义每页显示的记录数？
答：你可以在控制器中添加一个新的参数size，并传递给服务层。
@GetMapping("/users")
public String getUsers(@RequestParam(defaultValue = "0") int page, @RequestParam(defaultValue = "5") int size, Model model) {
Pageable pageable = PageRequest.of(page, size);
Page<User> users = paginationService.getUsers(pageable);
model.addAttribute("users", users);
model.addAttribute("currentPage", page);
model.addAttribute("totalPages", users.getTotalPages());
return "users";
}
然后在视图模板中添加一个表单来选择每页显示的记录数：
<form method="get" action="/users">
<select name="size" onchange="this.form.submit()">
<option value="5" th:selected="${size == 5}">5 per page</option>
<option value="10" th:selected="${size == 10}">10 per page</option>
<option value="20" th:selected="${size == 20}">20 per page</option>
</select>
</form>
这样，用户就可以通过下拉菜单选择每页显示的记录数了。
以上内容就是解答有关“Bootstrap和Java分页实例第二篇”的详细内容了，我相信这篇文章可以为您解决一些疑惑，有任何问题欢迎留言反馈，谢谢阅读。
原创文章，作者：K-seo，如若转载，请注明出处：https://www.kdun.cn/ask/716500.html
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