如何将字符串参数传递给自定义存储库方法？

Question

AJAX + Rest + Spring + MySQL有问题。请求是成功的，但是响应是空的，不管请求中使用的格式。事实上，请求有效负载显示了"customer“："MyCustomer”，所以我认为控制器中存在问题。

AJAX函数ajax_ciudad(customer) { // onchange复选框

$.ajax({
    type: "POST",
    contentType: "application/json",
    url: "/api/ciudades",
    data: JSON.stringify(customer),
    dataType: 'json',
    cache: false,
    timeout: 600000,
        }).then(function(data) {
            DO SOMETHING.... 
           });
        });

}

控制器

@RestController
@RequestMapping
public class SearchController {
@Autowired
    private MyRepository myRepository;
    @PostMapping("/api/ciudades")
    public @ResponseBody List<?> getSedes(String customer){

        List<Canal> ciudades = myRepository.findBySede(customer);
        return ciudades;
    }


REPOSITORY
    @Query(value ="SELECT * FROM canal WHERE cliente = ?1", nativeQuery = true)
    List<Canal> findBySede(@Param("customer") String customer);

..。始终返回空对象[]

在这里输入图像描述

我尝试过几种数据格式，我尝试使用.val()获取Select来获取字符串，使用.value获取html值.如果我手动设置一个参数(如myRepository.findBySede("MyString") )，ajax响应有信息，但是当我传递值时，它不工作；我做错了什么？谢谢你的帮忙

我的实体类

@Entity
@Table(name = "canal")
public class Canal { 

    @Id
    @GeneratedValue(strategy=GenerationType.IDENTITY)
    @Column(name = "idcanal", unique = true, nullable = false)
    int id;
    @Column(name = "cliente")
    String cliente;
    @Column(name = "ciudad")
    String ciudad;
    @Column(name = "sede")
    String sede;
    @Column(name = "canal")
    String canal;
    @Column(name = "ip_pe")
    String ip_pe;
    @Column(name = "nombre_pe")
    String nombre_pe;
    @Column(name = "ipwan_pe")
    String ipwan_pe;
    @Column(name = "puerto_pe")
    String puerto_pe    ;
    @Column(name = "ipwan_router")
    String ipwan_router;
    @Column(name = "enrutamiento")
    String enrutamiento;
    *****getters and setters****
     }

Answer 1

我希望您已经正确地定义了您的回购，并返回正确的数据，基于客户字符串。

从ajax "customer"传递为@Param，并像这样定义控制器，因为@RestController包括@Controller和@ResponseBody:

@RestController
public class SearchController {
    @Autowired
    private MyRepository myRepository;

    @PostMapping("/api/ciudades")
    public List<Canal> getSedes(@Param("customer") String customer){

        List<Canal> ciudades = myRepository.findBySede(customer);
        return ciudades;
    }

或者更好的方法，返回ResponseEntity。

@RestController
public class SearchController {
    @Autowired
    private MyRepository myRepository;

    @PostMapping("/api/ciudades")
    public ResponseEntity<?> getSedes(@Param("customer") String customer){

        List<Canal> ciudades = myRepository.findBySede(customer);
        return new ResponseEntity<>(ciudades , HttpStatus.OK);
    }

在repo中这样定义您的方法：

@Repository|
public interface MyRepository extends CrudRepository<Canal, String> 

    @Query(value ="SELECT * FROM canal GROUP BY cliente", nativeQuery = true)
    List<Canal> findByIdcanal(); // works fines

  //I assume here you have canal table and cliente is column in it as you 
   running native query

    @Query(value ="SELECT * FROM canal WHERE cliente = ?1", nativeQuery = true)
    List<Canal> findBySede(String customer); // doesn't work

  //OR try this as JPQL if you have Canal is entity and cliente as string type in it.
    @Query(value ="Select c from Canal c WHERE c.cliente = :cliente")
    List<Canal> findBySede(@Param("cliente") String customer); 

   //OR simply have Named query I assume you have Canal and cliente string type

   List<Canal> findByCliente(String customer); 


}

当我检查您的本机查询时，更新很好。

如果您希望在控制器中以@RequestBody的形式发送customer(string)，请遵循以下步骤：

1. 创建一个类客户 公共类客户{私有字符串客户；公共字符串getCustomer() {返回客户；}公共无效setCustomer(字符串客户){ this.customer = customer；} }
2. 以@RequestBody方式处理请求 @PostMapping("/api/ ciudades ")公共ResponseEntity getSedes(@RequestBody customer){ List ciudades=getSedes返回新的ResponseEntity<>(ciudades，HttpStatus.OK)；}