jpa,JPA,EntityManager,JPAQueryFactory

   jpa条件查询,or,and 使用
　　

　　 @Autowired
    private EntityManager entityManager;

    @Test
    public void test01() {

        CriteriaBuilder cb = entityManager.getCriteriaBuilder();
        CriteriaQuery<UserPO> query = cb.createQuery(UserPO.class);
        Root<UserPO> root = query.from(UserPO.class);
        Predicate id = cb.equal(root.get("id"), 2);
        Predicate id1 = cb.like(root.get("name"), "%现场%");
        Predicate or = cb.or(id, id1);
        query.where(or);
        List<UserPO> resultList = entityManager.createQuery(query).getResultList();
        resultList.forEach(r -> {
            r.setAccount("123");
        });
        System.out.println(one);
        System.out.println(resultList);

    }

 

entityManager修改
记得加上事务注解

import org.springframework.transaction.annotation.Transactional;

@Transactional

 entityManager.merge(taskAttributePO1);

 

JPAQueryFactory注入

需要先将这个类交由spring管理

@Configuration
public class BeanConfig {


    @Bean
    public JPAQueryFactory jpaQuery(EntityManager entityManager){
        return new JPAQueryFactory(entityManager);
    }

}

然后再使用注解注入即可

    @Resource
    private JPAQueryFactory jpaQueryFactory;

 

JPAQueryFactory用法

jpaQueryFactory = new JPAQueryFactory(entityManager);

        QUserPO userPO = QUserPO.userPO;
        JPAQuery<UserPO> query = jpaQueryFactory.select(QUserPO.userPO).from(userPO);
        BooleanExpression c = userPO.id.eq(2).or(userPO.id.eq(1)).or(userPO.id.eq(3));
        JPAQuery<UserPO> where = query.where(c);
        List<UserPO> fetch = where.fetch();
        System.out.println(fetch);

 

        /**
         * @Transactional事务使用总结：
         * 
         * 1、异常在A方法内抛出，则A方法就得加注解
         * 2、多个方法嵌套调用，如果都有 @Transactional 注解，则产生事务传递，默认 Propagation.REQUIRED
         * 3、如果注解上只写 @Transactional  默认只对 RuntimeException 回滚，而非 Exception 进行回滚
         * 如果要对 checked Exceptions 进行回滚，则需要 @Transactional(rollbackFor = Exception.class)
         * 
         * org.springframework.orm.jpa.JpaTransactionManager
         * 
         * org.springframework.jdbc.datasource.DataSourceTransactionManager
         * 
         * org.springframework.transaction.jta.JtaTransactionManager
         * 
         * 
         * 
         */

 

jpaQueryFactory根据条件删除

    QTaskGroupPersonPO taskGroupPersonPO = QTaskGroupPersonPO.taskGroupPersonPO;
        long execute =
                jpaQueryFactory.delete(taskGroupPersonPO).where(taskGroupPersonPO.taskGroupId.eq(taskGroupId)).execute();

 

获取jpa所有实体类   获取jpa的所有类，获取jpa所有实体类

       EntityManager em =  AppContextHolder.getBean(EntityManager.class);
        Map<String, EntityPersister> persistMap = ((MetamodelImpl)em.getMetamodel()).entityPersisters();