Spring Boot1中使用JPA例子

╰半夏微凉° 2022-05-22 08:44 195阅读 0赞

本文使用Spring Boot1.5.8版本，代码下载地址：  
[Spring Boot1中使用JPA例子][Spring Boot1_JPA]

最终项目目录如下图所示：  
![这里写图片描述][70]

# 新建Maven工程 #

pom.xml如下所示：

<?xml version="1.0" encoding="UTF-8"?>
    <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.wu.demo.springboot</groupId>
        <artifactId>jpademo</artifactId>
        <version>1.0-SNAPSHOT</version>
        <packaging>jar</packaging>
    
        <name>jpademo</name>
        <description>Demo project for Spring Boot JPA</description>
    
        <parent>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-parent</artifactId>
            <version>1.5.8.RELEASE</version>
            <relativePath/> 
        </parent>
    
        <properties>
            <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
            <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
            <java.version>1.8</java.version>
        </properties>
    
        <dependencies>
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-starter</artifactId>
            </dependency>
    
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-starter-test</artifactId>
                <scope>test</scope>
            </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>
        </dependencies>
    
        <build>
            <plugins>
                <plugin>
                    <groupId>org.springframework.boot</groupId>
                    <artifactId>spring-boot-maven-plugin</artifactId>
                </plugin>
            </plugins>
        </build>
    
    </project>

# 添加application.properties文件 #

spring.datasource.url=jdbc:mysql://localhost:3306/test
    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

# init.sql文件 #

这个文件不是项目必须的，里面存放了创建表的语句，如下所示：

drop table if exists user_test;
    create table user_test ( id varchar(32) primary key, username varchar(32), password varchar(32) );

# 创建Application #

package com.wu.demo.springboot.jpademo;
    
    import org.springframework.boot.SpringApplication;
    import org.springframework.boot.autoconfigure.SpringBootApplication;
    
    @SpringBootApplication
    public class Application {
    
        public static void main(String[] args) {
            SpringApplication.run(Application.class, args);
        }
    }

# 创建UserDO #

package com.wu.demo.springboot.jpademo.bean;
    
    import org.hibernate.annotations.GenericGenerator;
    
    import javax.persistence.*;
    
    @Entity
    @Table(name="user_test")
    public class UserDO { 
    
        @Id
        @GeneratedValue(generator = "uuid")
        @GenericGenerator(name = "uuid", strategy = "uuid")
        private String id;
    
        @Column
        private String username;
    
        @Column
        private String password;
    
        //此处节省篇幅，省略了get/set。
    }

# 创建Repository #

package com.wu.demo.springboot.jpademo.dao;
    
    import com.wu.demo.springboot.jpademo.bean.UserDO;
    import org.springframework.data.jpa.repository.JpaRepository;
    
    public interface UserRepository extends JpaRepository<UserDO, String>{
        UserDO findByUsername(String username);
    }

# 创建测试类 #

package com.wu.demo.springboot.jpademo.test;
    
    import com.wu.demo.springboot.jpademo.Application;
    import com.wu.demo.springboot.jpademo.bean.UserDO;
    import com.wu.demo.springboot.jpademo.dao.UserRepository;
    import org.junit.Test;
    import org.junit.runner.RunWith;
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.boot.test.context.SpringBootTest;
    import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
    
    @RunWith(SpringJUnit4ClassRunner.class)
    @SpringBootTest(classes = Application.class)
    public class RepositoryTest {
    
        @Autowired
        private UserRepository userRepository;
    
        @Test
        public void test() throws Exception {
    
            UserDO o = new UserDO();
            o.setUsername("root");
            o.setPassword("rootroot");
            userRepository.save(o);
    
            System.out.println(userRepository.findByUsername("root").getUsername());
        }
    }

参考资料：1、[springboot(二)：web综合开发][springboot_web]  
2、[springboot(五)：spring data jpa的使用][springboot_spring data jpa]

[Spring Boot1_JPA]: https://download.csdn.net/download/wu_boy/10570832
[70]: /images/20220522/b2348c6d7a4a4e07b6b41461321bda06.png
[springboot_web]: http://www.ityouknow.com/springboot/2016/02/03/spring-boot-web.html
[springboot_spring data jpa]: http://www.ityouknow.com/springboot/2016/08/20/spring-boo-jpa.html