这里有一个例子:

@GET
@Path("retrieve/{uuid}")
public Response retrieveSomething(@PathParam("uuid") String uuid) {
    if(uuid == null || uuid.trim().length() == 0) {
        return Response.serverError().entity("UUID cannot be blank").build();
    }
    Entity entity = service.getById(uuid);
    if(entity == null) {
        return Response.status(Response.Status.NOT_FOUND).entity("Entity not found for UUID: " + uuid).build();
    }
    String json = //convert entity to json
    return Response.ok(json, MediaType.APPLICATION_JSON).build();
}

看一下Response类。

请注意，您应该始终指定一个内容类型，特别是当您传递多个内容类型时，但如果每个消息都将表示为JSON，则可以使用@Produces("application/ JSON ")对方法进行注释。

JAX-RS支持标准/自定义HTTP代码。参见ResponseBuilder和ResponseStatus，例如:

http://jackson.codehaus.org/javadoc/jax-rs/1.0/javax/ws/rs/core/Response.ResponseBuilder.html#status%28javax.ws.rs.core.Response.Status%29

请记住，JSON信息更多的是与资源/应用程序关联的数据。HTTP代码更多的是关于被请求的CRUD操作的状态。(至少在REST-ful系统中是这样的)

The answer by hisdrewness will work, but it modifies the whole approach to letting a provider such as Jackson+JAXB automatically convert your returned object to some output format such as JSON. Inspired by an Apache CXF post (which uses a CXF-specific class) I've found one way to set the response code that should work in any JAX-RS implementation: inject an HttpServletResponse context and manually set the response code. For example, here is how to set the response code to CREATED when appropriate.

@Path("/foos/{fooId}")
@PUT
@Consumes("application/json")
@Produces("application/json")
public Foo setFoo(@PathParam("fooID") final String fooID, final Foo foo, @Context final HttpServletResponse response)
{
  //TODO store foo in persistent storage
  if(itemDidNotExistBefore) //return 201 only if new object; TODO app-specific logic
  {
    response.setStatus(Response.Status.CREATED.getStatusCode());
  }
  return foo;  //TODO get latest foo from storage if needed
}

改进:在找到另一个相关的答案后，我了解到可以将HttpServletResponse作为成员变量注入，甚至对于单例服务类(至少在RESTEasy中)!!这是一种比用实现细节污染API更好的方法。它看起来是这样的:

@Context  //injected response proxy supporting multiple threads
private HttpServletResponse response;

@Path("/foos/{fooId}")
@PUT
@Consumes("application/json")
@Produces("application/json")
public Foo setFoo(@PathParam("fooID") final String fooID, final Foo foo)
{
  //TODO store foo in persistent storage
  if(itemDidNotExistBefore) //return 201 only if new object; TODO app-specific logic
  {
    response.setStatus(Response.Status.CREATED.getStatusCode());
  }
  return foo;  //TODO get latest foo from storage if needed
}

如果您希望保持资源层的响应对象干净，那么我建议您使用@NameBinding和绑定到ContainerResponseFilter的实现。

下面是注释的主要内容:

package my.webservice.annotations.status;

import javax.ws.rs.NameBinding;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;

@NameBinding
@Retention(RetentionPolicy.RUNTIME)
public @interface Status {
  int CREATED = 201;
  int value();
}

这是过滤器的核心部分:

package my.webservice.interceptors.status;

import javax.ws.rs.container.ContainerRequestContext;
import javax.ws.rs.container.ContainerResponseContext;
import javax.ws.rs.container.ContainerResponseFilter;
import javax.ws.rs.ext.Provider;
import java.io.IOException;

@Provider
public class StatusFilter implements ContainerResponseFilter {

  @Override
  public void filter(ContainerRequestContext containerRequestContext, ContainerResponseContext containerResponseContext) throws IOException {
    if (containerResponseContext.getStatus() == 200) {
      for (Annotation annotation : containerResponseContext.getEntityAnnotations()) {
        if(annotation instanceof Status){
          containerResponseContext.setStatus(((Status) annotation).value());
          break;
        }
      }
    }
  }
}

然后你的资源的实现就变成了:

package my.webservice.resources;

import my.webservice.annotations.status.StatusCreated;
import javax.ws.rs.*;

@Path("/my-resource-path")
public class MyResource{
  @POST
  @Status(Status.CREATED)
  public boolean create(){
    return true;
  }
}

我没有使用JAX-RS，但我有一个类似的场景，我使用:

response.setStatus(HttpStatus.INTERNAL_SERVER_ERROR.value());

使用Microprofile OpenAPI扩展Nthalk的答案，您可以使用@APIResponse注释将返回代码与您的文档对齐。

这允许标记JAX-RS方法

@GET
@APIResponse(responseCode = "204")
public Resource getResource(ResourceRequest request) 

您可以使用ContainerResponseFilter解析这个标准化注释

@Provider
public class StatusFilter implements ContainerResponseFilter {

    @Override
    public void filter(ContainerRequestContext requestContext, ContainerResponseContext responseContext) {
        if (responseContext.getStatus() == 200) {
            for (final var annotation : responseContext.getEntityAnnotations()) {
                if (annotation instanceof APIResponse response) {
                    final var rawCode = response.responseCode();
                    final var statusCode = Integer.parseInt(rawCode);

                    responseContext.setStatus(statusCode);
                }
            }
        }
    }

}

当您在方法上添加多个注释时，就会出现警告

@APIResponse(responseCode = "201", description = "first use case")
@APIResponse(responseCode = "204", description = "because you can")
public Resource getResource(ResourceRequest request)