JPA（Java Persistence API）是一种Java持久化解决方案，负责把数据保存到数据库，实际上它就是一种标准、规范，而不是具体的实现。JPA属于重量级的，因为它需要运行在JAVA EE容器中，而Spring Data JPA提供了轻量级的实现，在任何servlet容器中都可以运行。

        Spring Data JPA相对于JAVA EE中的JPA，配置更简单，以轻量级的方式实现了部分在 EJB 容器环境下才具有的功能，将 EntityManager 的创建与销毁、事务管理等代码抽取出来，并由其统一管理，并且极大的简化了数据库访问层的代码。

//pom配置

　　　　
             
                 
     
      mysql
                  
     
      mysql-connector-java
                  
     
      runtime
              
             
                 
     
      org.springframework.boot
                  
     
      spring-boot-starter-data-jpa
              
             
                 
     
      org.springframework.boot
                  
     
      spring-boot-starter-thymeleaf
              
             
                 
     
      org.springframework.boot
                  
     
      spring-boot-starter-web
              
             
                 
     
      org.springframework.boot
                  
     
      spring-boot-starter-test
                  
     
      test
              
     //application.properties 配置

spring.freemarker.cache=false spring.datasource.url=jdbc:mysql://localhost:3306/test?useUnicode=true&useJDBCCompliantTimezoneShift=true&useLegacyDatetimeCode=false&serverTimezone=UTC spring.datasource.username=root spring.datasource.password=root spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver spring.jpa.database=mysql #是否显示sql语句 spring.jpa.show-sql=true #自动建表 spring.jpa.hibernate.ddl-auto=update

实现接口用于对实体操作

package com.zjx.springbootjpadata.jpainterface; import com.zjx.springbootjpadata.pojo.User; import org.springframework.data.jpa.repository.JpaRepository; import org.springframework.data.jpa.repository.JpaSpecificationExecutor; import java.io.Serializable; import java.util.List; /**  * JpaRepository 简单查询接口  * JpaSpecificationExecutor  复杂查询接口  * Serializable 序列化接口  */ public interface UserJpa extends JpaRepository
    
     , JpaSpecificationExecutor
     
      , Serializable {
      List
      
        findAllByUserName(String username); } 测试用例
      
     
    

package com.zjx.springbootjpadata; import com.zjx.springbootjpadata.jpainterface.UserJpa; import com.zjx.springbootjpadata.pojo.User; 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.SpringRunner; import java.util.ArrayList; import java.util.Iterator; import java.util.List; /**  * 使用SpringDataJPA完成数据的CRUD  */ @RunWith(SpringRunner.class) @SpringBootTest public class SpringbootjpadataApplicationTests {
      @Autowired     private UserJpa userjpa;     //新增     @Test     public void save(){
          User user = new User("张一","16","地球村");         userjpa.save(user);     }     //批量新增     @Test     public void saveAll(){
          ArrayList
    
      userList = new ArrayList
     
      ();         User user1 = new User("张一","10","地球村1号");         User user2 = new User("张二","11","地球村2号");         User user3 = new User("张三","12","地球村3号");         User user4 = new User("张四","13","地球村4号");         User user5 = new User("张五","14","地球村5号");         User user6 = new User("张六","15","地球村6号");         userList.add(user1);         userList.add(user2);         userList.add(user3);         userList.add(user4);         userList.add(user5);         userList.add(user6);         userjpa.saveAll(userList);     }     //查询所有     @Test     public void findAll(){
          List
      
        list = userjpa.findAll();         for(User u:list){
              System.out.println(u.toString());         }         System.out.println(list.size());     }     //查询     @Test     public void findByName(){
          List
       
         list = userjpa.findAllByUserName("张一");         for(User u:list){
              System.out.println(u.toString());         }         System.out.println(list.size());     }     //更新     @Test     public void updateName(){
          List
        
          list = userjpa.findAllByUserName("张一");         for(User u:list){
              u.setUserName("张");             userjpa.save(u);             System.out.println(u.toString());         }         System.out.println(list.size());     }     //删除     @Test     public void deleName(){
          List
         
           list = userjpa.findAllByUserName("张"); for(User u:list){ userjpa.delete(u); System.out.println(u.toString()); } System.out.println(list.size()); } }
         
        
       
      
     
    

以上是自学总结。有借鉴前辈帖子望见谅。不足之处请多多指教