spring boot2+jpa+thymeleaf增删改查例子
Posted gdjlc
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参考这遍文章做了一个例子，稍微不同之处，原文是spring boot、mysql，这里改成了spring boot 2、Oracle。
一、pom.xml引入相关模块web、jpa、thymeleaf、oracle：
<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>com.oracle</groupId> <artifactId>ojdbc8</artifactId> <version>12.2.0.1</version> </dependency>
二、application.properties配置
server.port = 9001 spring.datasource.driver-class-name = oracle.jdbc.driver.OracleDriver spring.datasource.url = jdbc:oracle:thin:@127.0.0.1:1521:testdb spring.datasource.username = dev spring.datasource.password = dev spring.jpa.hibernate.ddl-auto = update spring.jpa.show-sql = true spring.thymeleaf.cache = false
说明：
1、由于本机的8080已经被使用，修改一下端口号为9001。
2、hibernate.hbm2ddl.auto参数有四个值：
create： 每次加载hibernate时都会删除上一次的生成的表，然后根据你的model类再重新来生成新表，哪怕两次没有任何改变也要
这样执行，这就是导致数据库表数据丢失的一个重要原因。
create-drop ：每次加载hibernate时根据model类生成表，但是sessionFactory一关闭,表就自动删除。
update：最常用的属性，第一次加载hibernate时根据model类会自动建立起表的结构（前提是先建立好数据库），以后加载
hibernate时根据 model类自动更新表结构，即使表结构改变了但表中的行仍然存在不会删除以前的行。要注意的是当部署到服务器
后，表结构是不会被马上建立起来的，是要等 应用第一次运行起来后才会。
validate ：每次加载hibernate时，验证创建数据库表结构，只会和数据库中的表进行比较，不会创建新表，但是会插入新值。
3、show-sql 是否打印出自动生产的SQL，方便调试的时候查看
4、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。
三、启动类需要添加Servlet的支持
package com.example.demo; import org.springframework.boot.SpringApplication; import org.springframework.boot.autoconfigure.SpringBootApplication; import org.springframework.boot.builder.SpringApplicationBuilder; import org.springframework.boot.web.servlet.support.SpringBootServletInitializer; @SpringBootApplication public class DemoApplication extends SpringBootServletInitializer { @Override protected SpringApplicationBuilder configure(SpringApplicationBuilder application) { return application.sources(DemoApplication.class); } public static void main(String[] args) { SpringApplication.run(DemoApplication.class, args); } }
四、数据库层代码
1、实体类映射数据库表
package com.example.demo.entity; import javax.persistence.Column; import javax.persistence.Entity; import javax.persistence.GeneratedValue; import javax.persistence.Id; import javax.persistence.Table; import javax.validation.constraints.NotEmpty; import org.hibernate.validator.constraints.Length; @Entity @Table(name = "userinfo") public class User { @Id @GeneratedValue private long id; @Column(nullable = false, unique = true) @NotEmpty(message="用户名不能为空") private String userName; @Column(nullable = false) @NotEmpty(message="密码不能为空") @Length(min=6, message="密码长度不能少于6位") private String password; @Column(nullable = false) private int age; //必须有构造 public User() { } public long getId() { return id; } public User setId(long id) { this.id = id; return this; } public String getUserName() { return userName; } public User setUserName(String userName) { this.userName = userName; return this; } public String getPassword() { return password; } public User setPassword(String password) { this.password = password; return this; } public int getAge() { return age; } public User setAge(int age) { this.age = age; return this; } }
2、继承JpaRepository类会自动实现很多内置的方法
package com.example.demo.repository; import org.springframework.data.jpa.repository.JpaRepository; import com.example.demo.entity.User; public interface UserRepository extends JpaRepository<User, Long> { User findById(long id); void deleteById(Long id); }
五、业务层
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。
1、UserService.java
package com.example.demo.service; import java.util.List; import org.springframework.data.domain.Page; import org.springframework.data.domain.Pageable; import com.example.demo.entity.User; public interface UserService { public Page<User> getUserPage(Pageable pageable); public List<User> getUserList(); public User findUserById(long id); public void save(User user); public void edit(User user); public void delete(long id); }
2、UserServiceImpl.java
package com.example.demo.service.impl; import java.util.List; import java.util.Optional; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.data.domain.Page; import org.springframework.data.domain.Pageable; import org.springframework.stereotype.Service; import com.example.demo.entity.User; import com.example.demo.repository.UserRepository; import com.example.demo.service.UserService; @Service public class UserServiceImpl implements UserService { @Autowired private UserRepository userRepository; @Override public Page<User> getUserPage(Pageable pageable) { return userRepository.findAll(pageable); } @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.deleteById(id); } }
六、控制层
package com.example.demo.web.controller; import java.util.List; import javax.annotation.Resource; import javax.validation.Valid; import org.springframework.data.domain.Page; import org.springframework.data.domain.PageRequest; import org.springframework.data.domain.Pageable; import org.springframework.data.domain.Sort; import org.springframework.data.domain.Sort.Direction; import org.springframework.stereotype.Controller; import org.springframework.ui.Model; import org.springframework.validation.BindingResult; import org.springframework.validation.ObjectError; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.bind.annotation.ResponseBody; import com.example.demo.entity.User; import com.example.demo.service.UserService; @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); /*int page=1,size=2; Sort sort = new Sort(Direction.DESC, "id"); Pageable pageable = PageRequest.of(page, size, sort); model.addAttribute("users", pageable);*/ return "user/list"; } @RequestMapping("/toAdd") public String toAdd() { return "user/userAdd"; } @RequestMapping("/add") public @ResponseBody User add(@Valid User user, BindingResult result) { if (result.hasErrors()) { List<ObjectError> list = result.getAllErrors(); for (ObjectError error : list) { System.out.println(error.getDefaultMessage()); } return null; } userService.save(user); return user; } @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"; } }
七、页面
1、列表页 list.hmtl
<!DOCTYPE html> <html lang="en" 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 class="container"> <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=${user.id})}">delete</a></td> </tr> </tbody> </table> </div> <div class="form-group"> <div class="col-sm-2 control-label"> <a href="/toAdd" th:href="@{/toAdd}" class="btn btn-info">add</a> </div> </div> </body> </html>
2、新增页 userAdd.html
<!DOCTYPE html> <html lang="en" xmlns:th="http://www.thymeleaf.org"> <head> <meta charset="UTF-8"/> <title>user</title> <link rel="stylesheet" th:href="@{/css/bootstrap.css}"></link> </head> <body class="container"> <br/> <h1>添加用户</h1> <br/><br/> <div class="with:80%"> <form class="form-horizontal" th:action="@{/add}" method="post"> <div class="form-group"> <label for="userName" class="col-sm-2 control-label">userName</label> <div class="col-sm-10"> <input type="text" class="form-control" name="userName" id="userName" placeholder="userName"/> </div> </div> <div class="form-group"> <label for="password" class="col-sm-2 control-label" >Password</label> <div class="col-sm-10"> <input type="password" class="form-control" name="password" id="password" placeholder="Password"/> </div> </div> <div class="form-group"> <label for="age" class="col-sm-2 control-label">age</label> <div class="col-sm-10"> <input type="text" class="form-control" name="age" id="age" placeholder="age"/> </div> </div> <div class="form-group"> <div class="col-sm-offset-2 col-sm-10"> <input type="submit" value="Submit" class="btn btn-info" /> <input type="reset" value="Reset" class="btn btn-info" /> </div> </div> </form> </div> </body> </html>
3、修改页 userEdit.html
<!DOCTYPE html> <html lang="en" xmlns:th="http://www.thymeleaf.org"> <head> <meta charset="UTF-8"/> <title>user</title> <link rel="stylesheet" th:href="@{/css/bootstrap.css}"></link> </head> <body class="container"> <br/> <h1>修改用户</h1> <br/><br/> <div class="with:80%"> <form class="form-horizontal" th:action="@{/edit}" th:object="${user}" method="post"> <input type="hidden" name="id" th:value="*{id}" /> <div class="form-group"> <label for="userName" class="col-sm-2 control-label">userName</label> <div class="col-sm-10"> <input type="text" class="form-control" name="userName" id="userName" th:value="*{userName}" placeholder="userName"/> </div> </div> <div class="form-group"> <label for="password" class="col-sm-2 control-label" >Password</label> <div class="col-sm-10"> <input type="password" class="form-control" name="password" id="password" th:value="*{password}" placeholder="Password"/> </div> </div> <div class="form-group"> <label for="age" class="col-sm-2 control-label">age</label> <div class="col-sm-10"> <input type="text" class="form-control" name="age" id="age" th:value="*{age}" placeholder="age"/> </div> </div> <div class="form-group"> <div class="col-sm-offset-2 col-sm-10"> <input type="submit" value="Submit" class="btn btn-info" /> 以上是关于spring boot2+jpa+thymeleaf增删改查例子的主要内容，如果未能解决你的问题，请参考以下文章
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