SpringBoot整合JPA

Posted 2020-12-30 缘故为何

1.创建SpringBoot项目

 

2.pom.xml添加JPA依赖，数据库mysql依赖包

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
	xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
	<modelVersion>4.0.0</modelVersion>

	<groupId>com.tao</groupId>
	<artifactId>springboot_jpa</artifactId>
	<version>0.0.1-SNAPSHOT</version>
	<packaging>jar</packaging>

	<name>springboot_jpa</name>
	<url>http://maven.apache.org</url>

	<properties>
		<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
	</properties>
	<parent>
		<groupId>org.springframework.boot</groupId>
		<artifactId>spring-boot-starter-parent</artifactId>
		<version>1.5.12.RELEASE</version>
	</parent>
	<dependencies>
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-web</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>
		<dependency>
			<groupId>junit</groupId>
			<artifactId>junit</artifactId>
			<version>3.8.1</version>
			<scope>test</scope>
		</dependency>
	</dependencies>
</project>

3.在src/main/resouces配置application.properties

server.port: 9998

debug:true

#PRODUCTION
spring.datasource.url: jdbc:mysql://127.0.0.1:3306/springboot_jpa?useUnicode=true&characterEncoding=UTF-8

spring.datasource.driverClassName: com.mysql.jdbc.Driver
spring.datasource.username: root
spring.datasource.password: root
spring.datasource.jmx-enabled=true
spring.datasource.test-on-borrow=true
spring.datasource.validation-query=SELECT 1

spring.jpa.database = MYSQL
spring.jpa.database-platform=org.hibernate.dialect.MySQLDialect
spring.jpa.generate-ddl:true
spring.jpa.hibernate.show_sql:true
#第一次create 以后update
spring.jpa.hibernate.ddl-auto:create

4.com.tao.springboot_jpa.model下建立User

package com.tao.springboot_jpa.model;

import java.io.Serializable;

import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;

@Entity
public class User implements Serializable{
	private static final long serialVersionUID = 1L;
	@Id @GeneratedValue
	private Long id;
	@Column(name = "name")
	private String name;
	private String password;
	public Long getId() {
		return id;
	}
	public void setId(Long id) {
		this.id = id;
	}
	public String getName() {
		return name;
	}
	public void setName(String name) {
		this.name = name;
	}
	public String getPassword() {
		return password;
	}
	public void setPassword(String password) {
		this.password = password;
	}
}

5.在com.tao.springboot_jpa.repository下建立UserRepository

package com.tao.springboot_jpa.repository;

import java.util.List;

import javax.transaction.Transactional;

import org.springframework.data.jpa.repository.JpaRepository;
import org.springframework.data.jpa.repository.Query;
import org.springframework.stereotype.Repository;

import com.tao.springboot_jpa.model.User;
@Repository
@Transactional
public interface UserRepository extends JpaRepository<User, Long>{
	/**
	 * 通过用户名查询
	 * @param name
	 * @return
	 */
	List<User> findByName(String name);
	/**
	 * 自定义SQL查询
	 * @param id
	 * @return
	 */
	@Query(value = "select id from user where id = ?1",nativeQuery = true)
	Long findId(Long id);
}

6.在com.tao.springboot_jpa.action下建立UserAction

package com.tao.springboot_jpa.action;

import java.util.List;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RestController;

import com.tao.springboot_jpa.model.User;
import com.tao.springboot_jpa.service.UserService;

@RestController
@EnableAutoConfiguration
@RequestMapping(value = "/users", method = RequestMethod.POST)
public class UserAction {
	@Autowired
	private UserService userService;
	
	/**
	 * 通过用户名查询用户
	 * @param name
	 * @return
	 */
	@RequestMapping(value = "/findByName")
	public List<User> findByName(String name){
		return this.userService.findByName(name);
	}
	/**
	 * 通过ID查询ID
	 * @param id
	 * @return
	 */
	@RequestMapping(value = "/findId")
	public Long findId(Long id){
		return this.userService.findId(id);
	}
}

7.在com.tao.springboot_jpa.service下建立UserService

package com.tao.springboot_jpa.service;

import java.util.List;

import javax.transaction.Transactional;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.jpa.repository.JpaRepository;
import org.springframework.stereotype.Service;

import com.tao.springboot_jpa.model.User;
import com.tao.springboot_jpa.repository.UserRepository;

@Service
@Transactional
public class UserService {
	private final UserRepository userRepository;

	@Autowired
	public UserService(UserRepository userRepository) {
		super();
		this.userRepository = userRepository;
	}
	public JpaRepository<User, Long> getEntityRepository(){
        return this.userRepository;
    }
	public List<User> findByName(String name){
		return this.userRepository.findByName(name);
	}
	public Long findId(Long id){
		return this.userRepository.findId(id);
	}
	
	
}

8.运行测试

http://localhost:9998/users/findId?id=1

http://localhost:9998/users/findByName?name=tom