jpa,querydsl

[TOC]

# jpa

## 生成通用模板

實現自定義方法有兩種方法：

1. 根據衍生規則進行實現，此種狀況簡單； 查詢方法衍生規則  http://docs.spring.io/spring-data/jpa/docs/1.10.1.RELEASE/reference/html/#repositories.query-methods.query-creation    

2. 本身編寫接口 OrderRepositoryExt

    - 在接口中添加自定義方法

    - OrderRepository繼承此接口

    - OrderRepositoryImpl 實現此接口，這個實現類命名規則是必定的，在OrderRepository的基礎上加Impl；spring基礎會探測到此種狀況，注入OrderRepository就能夠了

### OrderRepository

```

public interface OrderRepository extends PagingAndSortingRepository<OrderEntity, String>, QueryDslPredicateExecutor<OrderEntity>, OrderRepositoryExt {

    /**

     * 根據渠道號和訂單編號查詢訂單

     *

     * @param orderNo

     * @param chanNo

     * @return

     */

    public OrderEntity findFirstByOrderNoAndChanNo(String orderNo, String chanNo);

}

```

### OrderRepositoryExt

```

public interface OrderRepositoryExt {

 

    public OrderEntity findByOrderNo(String orderNo);

}

```

### OrderRepositoryImpl

```

public class OrderRepositoryImpl implements OrderRepositoryExt {

 

    @Autowired

    private OrderRepository orderRepository;

 

    @Override

    public OrderEntity findByOrderNo(String orderNo) {

        QOrderEntity qOrderEntity = QOrderEntity.orderEntity;

        Predicate predicate = qOrderEntity.orderNo.eq(orderNo);

        return orderRepository.findOne(predicate);

    }

}

```

### 使用方法

```

@RestController

@RequestMapping("/test")

public class OrderController {

    private static Logger log = LoggerFactory.getLogger(OrderController.class);

 

    @Autowired

    private OrderRepository repository;

 

 

    @RequestMapping("/orders")

    public Object order() {

        OrderEntity orderEntity = new OrderEntity();

        orderEntity.setId(UUID.randomUUID().toString());

        orderEntity.setAccountId("111");

        orderEntity.setAmount(new BigDecimal(10));

        orderEntity.setChanNo("1111");

        orderEntity.setCreateAt(new Date());

        orderEntity.setOrderNo(UUID.randomUUID().toString());

        orderEntity.setOrderStatus("execed_success");

        orderEntity.setOrderType("INVEST");

        orderEntity.setProductId("2222");

        orderEntity.setTransactTime(new Date());

        orderEntity.setProductName("12312");

        orderEntity.setUpdateAt(new Date());

        repository.save(orderEntity);

 

        log.info("save-{}", JSONUtil.toJson(repository.findFirstByOrderNoAndChanNo(orderEntity.getOrderNo(), orderEntity.getChanNo())));

 

        orderEntity.setProductName("update");

        repository.save(orderEntity);

        log.info("update-{}", JSONUtil.toJson(repository.findByOrderNo(orderEntity.getOrderNo())));

 

        log.info("all ={}", JSONUtil.toJson(repository.findAll()));

        List<String> ids = new ArrayList<>();

        ids.add("11111");

        return null;

    }

```

## 手動編寫hql查詢

實體對象idea識別不出來

來自爲知筆記(Wiz)