Spring Boot深入学习数据访问之Spring Data JPA与Hibernate的应用

<dependency>
 <groupId>org.springframework.boot</groupId>
 <artifactId>spring-boot-starter-data-jpa</artifactId>
</dependency>

<?xml version="1.0" encoding="UTF-8"?>
-<project xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://maven.apache.org/POM/4.0.0">
<modelVersion>4.0.0</modelVersion>
-<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.1.7.RELEASE</version>
<relativePath/>
<!-- lookup parent from repository -->
</parent>
<groupId>com.ch</groupId>
<artifactId>ch6_1</artifactId>
<version>0.0.1-SNAPSHOT</version>
<name>ch6_1</name>
<description>Demo project for Spring Boot</description>
-<properties>
<java.version>11</java.version>
</properties>
-<dependencies>
-<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-data-jpa</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-web</artifactId>
</dependency>
<!-- 添加MySQL依赖 -->
-<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>5.1.45</version>
<!-- MySQL8.x时，请使用8.x的连接器 -->
</dependency>
-<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
</dependencies>
-<build>
-<plugins>
-<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
</build>
</project>

package com.ch.ch6_1.entity;
import java.io.Serializable;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.Table;
@Entity
@Table(name = "user_table")
/**
 * 如果没写表名，默认为类名的词组
 * （如MyUser类对应的表名为my_user）
 */
public class MyUser implements Serializable{
	private static final long serialVersionUID = 1L;
	@Id
	@GeneratedValue(strategy = GenerationType.IDENTITY)
	private int id;//主键
	/**使用@Column注解，可以配置列相关属性（列名，长度等），
	 * 可以省略，默认为属性名小写
	 */
	private String uname;
	private String usex;
	private int age;
	public int getId() {
		return id;
	}
	public void setId(int id) {
		this.id = id;
	}
	public String getUname() {
		return uname;
	}
	public void setUname(String uname) {
		this.uname = uname;
	}
	public String getUsex() {
		return usex;
	}
	public void setUsex(String usex) {
		this.usex = usex;
	}
	public int getAge() {
		return age;
	}
	public void setAge(int age) {
		this.age = age;
	}
}

package com.ch.ch6_1.repository;
import java.util.List;
import org.springframework.data.jpa.repository.JpaRepository;
import com.ch.ch6_1.entity.MyUser;
/**
 * 这里不需要使用@Repository注解数据访问层，
 * 因为Spring Boot自动配置了JpaRepository
 */
public interface UserRepository extends JpaRepository<MyUser, Integer>{
	public MyUser findByUname(String uname);
	public List<MyUser> findByUnameLike(String uname);
}

package com.ch.ch6_1.service;
import java.util.List;
import com.ch.ch6_1.entity.MyUser;
public interface UserService {
	public void saveAll();
	public List<MyUser> findAll();
	public MyUser findByUname(String uname);
	public List<MyUser> findByUnameLike(String uname);
	public MyUser getOne(int id);
}

package com.ch.ch6_1.service;
import java.util.ArrayList;
import java.util.List;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;
import com.ch.ch6_1.entity.MyUser;
import com.ch.ch6_1.repository.UserRepository;
@Service
@Transactional
public class UserServiceImpl implements UserService{
	@Autowired
	private UserRepository userRepository;//依赖注入数据访问层
	@Override
	public void saveAll() {
		MyUser mu1 = new MyUser();
		mu1.setUname("陈恒1");
		mu1.setUsex("男");
		mu1.setAge(88);
		MyUser mu2 = new MyUser();
		mu2.setUname("陈恒2");
		mu2.setUsex("女");
		eLike(String uname) {
		return userRepository.findByUnameLike("%" + uname + "%");
	}
	@Override
	public MyUser getOne(int id) {
		//调用父接口中的方法getOne
		return userRepository.getOne(id);
	}
}

package com.ch.ch6_1.controller;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.ResponseBody;
import com.ch.ch6_1.service.UserService;
@Controller
public class UserTestController {
	@Autowired
	private UserService userService;
	@RequestMapping("/save")
	@ResponseBody
	public String save() {
		userService.saveAll();
		return "保存用户成功！";
	}
	}
	@RequestMapping("/findAll")
	public String findAll(Model model){
		model.addAttribute("title", "查询所有用户");
		model.addAttribute("allUsers",userService.findAll());
		return "showAll";
	}
	@RequestMapping("/findByUnameLike")
	public String findByUnameLike(String uname, Model model){
		model.addAttribute("title", "根据用户名模糊查询所有用户");
		model.addAttribute("allUsers",userService.findByUnameLike(uname));
		return "showAll";
	}
}

<!DOCTYPE html>
<html xmlns:th="http://www.thymeleaf.org">
<head>
<meta charset="UTF-8">
<title>显示查询结果</title>
<link rel="stylesheet" th:href="@{css/bootstrap.min.css}" rel="external nofollow"  />
<link rel="stylesheet" th:href="@{css/bootstrap-theme.min.css}" rel="external nofollow"  />
</head>
<body>
	<div class="panel panel-primary">
		<div class="panel-heading">
			<h3 class="panel-title">Spring Data JPA简单查询</h3>
		</div>
	</div>
	<div class="container">
		<div class="panel panel-primary">
			<div class="panel-heading">
				<h3 class="panel-title"><span th:text="${title}"></span></h3>
			</div>
			<div class="panel-body">
				<div class="table table-responsive">
					<tab
							</tr>
						</tbody>
					</table>
				</div>
			</div>
		</div>
	</div>
</body>
</html>