springboot 之JPA

1、添加pom.xml

<?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>2.2.1.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.example</groupId>
    <artifactId>jpa</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>jpa</name>
    <description>Demo project for Spring Boot</description>

    <properties>
        <java.version>1.8</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-web</artifactId>
        </dependency>
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>druid</artifactId>
            <version>1.1.0</version>
        </dependency>
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <scope>runtime</scope>
        </dependency>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <optional>true</optional>
        </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>
    </dependencies>

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

</project>

2、application.yml

#默认使用配置
spring:
  profiles:
    active: dev
  redis:
    host: 127.0.0.1
    port: 6379
    password:
    lettuce:
      pool:
        max-active: 100
        max-idle: 10
        max-wait: 100000
#公共配置与profiles选择无关
mybatis-plus:
  typeAliasesPackage: com.yangwj.separate.entity
  mapperLocations: classpath:mapper/*.xml

logging:
  level:
    com.yangwj.separate.dao: debug

---

#开发配置
spring:
  profiles: dev

  datasource:
    url: jdbc:mysql://localhost:3306/test?useUnicode=true&characterEncoding=utf-8&useSSL=true&serverTimezone=GMT%2B8
    #url: jdbc:mysql://localhost:3306/test
    username: root
    password: yang156122
    driver-class-name: com.mysql.jdbc.Driver
    # 使用druid数据源
    type: com.alibaba.druid.pool.DruidDataSource

#jasypt:
#  encryptor:
#    password: yangwj

---
#开发配置
spring:
  profiles: test

  datasource:
    url: jdbc:mysql://localhost:3306/test1?useUnicode=true&characterEncoding=utf-8&useSSL=true&serverTimezone=GMT%2B8
    #url: jdbc:mysql://localhost:3306/test
    username: root
    password: yang156122
    driver-class-name: com.mysql.jdbc.Driver
    # 使用druid数据源
    type: com.alibaba.druid.pool.DruidDataSource

3、controller层

package com.example.jpa.controller;

import com.example.jpa.Dao.UserMapper;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

@RestController
public class UserController {

    @Autowired
    private UserMapper userMapper;

    @RequestMapping("/get")
    public String getUser() {
        return userMapper.findAll().toString();
    }
}

4、Dao层

package com.example.jpa.Dao;

import com.example.jpa.entityPO.User;
import org.springframework.data.jpa.repository.JpaRepository;

public interface UserMapper extends JpaRepository<User,String> {

}

5、PO层

package com.example.jpa.entityPO;

import lombok.Data;

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

@Entity
@Table(name = "user_t")
@Data
public class User {
    @Id
    private  int id;
    @Column(name = "user_name")
    private  String userName;
    @Column(name = "phone_number")
    private  String phoneNumber;
    private  String password;
    private  String age;
    private  String sex;

}

运行就可以了