这篇文章就不在介绍什么是jpa、thymeleaf,如果还不了解这些基本的概念,可以先移步前两篇相关文章。
pom包配置
pom包里面添加jpa和thymeleaf的相关包引用
<dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-thymeleaf</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-data-jpa</artifactId> </dependency> <dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> </dependency>
在application.Properties中添加配置 spring.datasource.url=jdbc:mysql://127.0.0.1/test?useUnicode=true&characterEncoding=utf-8&serverTimezone=UTC&useSSL=true spring.datasource.username=root spring.datasource.password=root spring.datasource.driver-class-name=com.mysql.jdbc.Driver spring.jpa.properties.hibernate.hbm2ddl.auto=update spring.jpa.properties.hibernate.dialect=org.hibernate.dialect.MySQL5InnoDBDialect spring.jpa.show-sql= true spring.thymeleaf.cache=false
其中propertiesspring.thymeleaf.cache=false
是关闭thymeleaf的缓存,不然在开发过程中修改页面不会立刻生效需要重启,生产可配置为true。
在项目resources目录下会有两个文件夹:static目录用于放置网站的静态内容如css、js、图片;templates目录用于放置项目使用的页面模板。
启动类需要添加Servlet的支持
@springbootApplication public class JpaThymeleafApplication extends SpringBootServletInitializer { @Override protected SpringApplicationBuilder configure(SpringApplicationBuilder application) { return application.sources(JpaThymeleafApplication.class); } public static void main(String[] args) throws Exception { SpringApplication.run(JpaThymeleafApplication.class, args); } }
实体类映射数据库表
@Entity public class User { @Id @GeneratedValue private long id; @Column(nullable = false, unique = true) private String userName; @Column(nullable = false) private String password; @Column(nullable = false) private int age; ... }
继承JpaRepository类会自动实现很多内置的方法,包括增删改查。也可以根据方法名来自动生成相关sql
public interface UserRepository extends JpaRepository<User, Long> { User findById(long id); Long deleteById(Long id); }
service调用jpa实现相关的增删改查,实际项目中service层处理具体的业务代码。
@Service public class UserServiceImpl implements UserService{ @Autowired private UserRepository userRepository; @Override public List<User> getUserList() { return userRepository.findAll(); } @Override public User findUserById(long id) { return userRepository.findById(id); } @Override public void save(User user) { userRepository.save(user); } @Override public void edit(User user) { userRepository.save(user); } @Override public void delete(long id) { userRepository.delete(id); } }
Controller负责接收请求,处理完后将页面内容返回给前端。
@Controller public class UserController { @Resource UserService userService; @RequestMapping("/") public String index() { return "redirect:/list"; } @RequestMapping("/list") public String list(Model model) { List<User> users=userService.getUserList(); model.addAttribute("users", users); return "user/list"; } @RequestMapping("/toAdd") public String toAdd() { return "user/userAdd"; } @RequestMapping("/add") public String add(User user) { userService.save(user); return "redirect:/list"; } @RequestMapping("/toEdit") public String toEdit(Model model,Long id) { User user=userService.findUserById(id); model.addAttribute("user", user); return "user/userEdit"; } @RequestMapping("/edit") public String edit(User user) { userService.edit(user); return "redirect:/list"; } @RequestMapping("/delete") public String delete(Long id) { userService.delete(id); return "redirect:/list"; } }
return "user/userEdit";
代表会直接去resources目录下找相关的文件。
return "redirect:/list";
代表转发到对应的controller,这个示例就相当于删除内容之后自动调整到list请求,然后再输出到页面。
list列表
<!DOCTYPE html> <html xmlns:th="http://www.thymeleaf.org"> <head> <meta charset="UTF-8"/> <title>userList</title> <link rel="stylesheet" th:href="@{/css/bootstrap.css}"></link> </head> <body> <br/> <h1>用户列表</h1> <br/><br/> <div class="with:80%"> <table class="table table-hover"> <thead> <tr> <th>#</th> <th>User Name</th> <th>Password</th> <th>Age</th> <th>Edit</th> <th>Delete</th> </tr> </thead> <tbody> <tr th:each="user : ${users}"> <th scope="row" th:text="${user.id}">1</th> <td th:text="${user.userName}">neo</td> <td th:text="${user.password}">Otto</td> <td th:text="${user.age}">6</td> <td><a th:href="@{/toEdit(id=${user.id})}">edit</a></td> <td><a th:href="@{/delete(id=${user.id})}">delete</a></td> </tr> </tbody> </table> </div> <div> <div class="col-sm-2 control-label"> <a href="/toAdd" th:href="@{/toAdd}" class="btn btn-info">add</a> </div> </div> </body> </html>
效果图:
<tr th:each="user : ${users}">
这里会从controler层model set的对象去获取相关的内容,th:each
表示会循环遍历对象内容。
其实还有其它的写法,具体的语法内容可以参考这篇文章:springboot(四):thymeleaf使用详解
修改页面:
<!DOCTYPE html> <html xmlns:th="http://www.thymeleaf.org"> <head> <meta charset="UTF-8"/> <title>user</title> <link rel="stylesheet" th:href="@{/css/bootstrap.css}"></link> </head> <body> <br/> <h1>修改用户</h1> <br/><br/> <div class="with:80%"> <form th:action="@{/edit}" th:object="${user}" method="post"> <input type="hidden" name="id" th:value="*{id}" /> <div> <label for="userName" class="col-sm-2 control-label">userName</label> <div> <input type="text" name="userName" id="userName" th:value="*{userName}" placeholder="userName"/> </div> </div> <div> <label for="password" class="col-sm-2 control-label" >Password</label> <div> <input type="password" name="password" id="password" th:value="*{password}" placeholder="Password"/> </div> </div> <div> <label for="age" class="col-sm-2 control-label">age</label> <div> <input type="text" name="age" id="age" th:value="*{age}" placeholder="age"/> </div> </div> <div> <div class="col-sm-offset-2 col-sm-10"> <input type="submit" value="Submit" class="btn btn-info" /> <a href="/toAdd" th:href="@{/list}" class="btn btn-info">Back</a> </div> </div> </form> </div> </body> </html>
添加页面和修改类似就不在贴代码了。
效果图:
这样一个使用jpa和thymeleaf的增删改查示例就完成了。