验证失败时包含参数名称的java自定义错误消息

Question

我希望我的API在请求缺少所需参数时返回errorMessage。例如，假设有一种方法：

@GET
@Path("/{foo}")
public Response doSth(@PathParam("foo") String foo, @NotNull @QueryParam("bar") String bar, @NotNull @QueryParam("baz") String baz)

其中@NotNull来自包javax.validation.constraints

我编写了一个异常映射程序，如下所示：

@Provider
public class Mapper extends ExceptionMapper<ConstraintViolationException> {

  @Override
  public Response toResponse(ConstraintViolationException) {
    Iterator<ConstraintViolation<?>> it= exception.getConstraintViolations().iterator();
    StringBuilder sb = new StringBuilder();
    while(it.hasNext()) {
      ConstraintViolation<?> next = it.next();
      sb.append(next.getPropertyPath().toString()).append(" is null");
    }
    // create errorMessage entity and return it with apropriate status
  }

但是next.getPropertyPath().toString()以method_name.arg_no格式返回字符串，f.e.fooBar.arg1 is null

我想接收输出fooBar.baz is null或者干脆baz is null

我的解决方案是为javac包含-parameters参数，但没有效果

也许我可以通过使用过滤器来实现：

public class Filter implements ContainerResponseFilter {

@Override
public void filter(ContainerRequestContext requestContext, ContainerResponseContext responseContext) {

    UriInfo uriInfo = requestContext.getUriInfo();
    UriRoutingContext routingContext = (UriRoutingContext) uriInfo;

    Throwable mappedThrowable = routingContext.getMappedThrowable();

    if (mappedThrowable != null) {
        Method resourceMethod = routingContext.getResourceMethod();
        Parameter[] parameters = resourceMethod.getParameters();

      // somehow transfer these parameters to exceptionMapper (?)
    }
  }
}

上述想法的唯一问题是先执行exoptionMapper，然后执行过滤器。此外，我也不知道如何在ExceptionMapper和Filter之间传输errorMessage。也许还有别的办法

Answer 1

可以将^{}注入异常映射器以获取资源方法

@Provider
public class Mapper extends ExceptionMapper<ConstraintViolationException> {

    @Context
    private ResourceInfo resourceInfo;

    @Override
    public Response toResponse(ConstraintViolationException ex) {
        Method resourceMethod = resourceInfo.getResourceMethod();
        Parameter[] parameters = resourceMethod.getParameters();
    }
}