1-1SPRING-BOOT-JPA入门

1.1 官网下载 https://start.spring.io/ ,下载项目，目前版本 <version>2.2.0.RELEASE</version>

主POM文件

<?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 https://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.2.0.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.leilei</groupId>
    <artifactId>spring-boot-crm</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>spring-boot-crm</name>
    <description>Demo project for Spring Boot</description>

    <properties>
        <java.version>1.8</java.version>
    </properties>

    <dependencies>
        <!--MySQL连接驱动-->
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
        </dependency>

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

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
            <exclusions>
                <exclusion>
                    <groupId>org.junit.vintage</groupId>
                    <artifactId>junit-vintage-engine</artifactId>
                </exclusion>
            </exclusions>
        </dependency>
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.11</version>
            <scope>test</scope>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>

</project>

 

1.2 设置 apoplications.properties文件

spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver
spring.datasource.url=jdbc:mysql://localhost:3306/woleilei?characterEncoding=utf8&useSSL=false&serverTimezone=PRC&rewriteBatchedStatements=true
spring.datasource.username=root
spring.datasource.password=123456
#jpa相关配置
spring.jpa.show-sql=true
spring.jpa.hibernate.ddl-auto=update

 

1.3 创建package domain,用于存放java的实体类

package com.leilei.springbootcrm.domain;

import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import java.io.Serializable;
import java.util.Date;

@Entity
public class Company implements Serializable {
    private static final long serialVersionUID = 7471779949543151367L;

    @GeneratedValue
    @Id
    private Integer id;

    @Column(length = 50, nullable = false)
    private String CompanyName;

    private Date createTime;

    public Integer getId() {
        return id;
    }

    public void setId(Integer id) {
        this.id = id;
    }

    public String getCompanyName() {
        return CompanyName;
    }

    public void setCompanyName(String companyName) {
        CompanyName = companyName;
    }

    public Date getCreateTime() {
        return createTime;
    }

    public void setCreateTime(Date createTime) {
        this.createTime = createTime;
    }

    @Override
    public String toString() {
        return "Company{" +
                "id=" + id +
                ", CompanyName='" + CompanyName + '\'' +
                ", createTime=" + createTime +
                '}';
    }
}

 

1.4 创建dao package

package com.leilei.springbootcrm.dao;

import com.leilei.springbootcrm.domain.Company;
import org.springframework.data.jpa.repository.JpaRepository;

public interface CompanyDao extends JpaRepository<Company, Integer> {
}

 

1.5 创建 CompanyDaoTest 文件，以及创建一个插入的方法

package com.leilei.springbootcrm.dao;

import com.leilei.springbootcrm.domain.Company;
import org.junit.jupiter.api.Test;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;

import java.util.Date;

@SpringBootTest
class CompanyDaoTest {

    @Autowired
    private CompanyDao companyDao;

    @Test
    void testInsert() {
        System.out.println("=====start=====");
        Company company = new Company();
        company.setCompanyName("测试公司");
        company.setCreateTime(new Date());
        Company res = companyDao.save(company);
        System.out.println(res);
    }
}

 

1.6 完成运行测试文件，控制台可以看见 打印的sql .