无法使用POST方法返回JSON对象

Question

我正在写一篇Jersey 2 Restful网络服务。这是服务类：

package com.Test.PS;
import java.io.IOException;
import javax.ws.rs.GET;
import javax.ws.rs.Path;
import javax.ws.rs.Produces;
import javax.ws.rs.core.MediaType;
import javax.ws.rs.QueryParam;
import javax.ws.rs.Consumes;
import javax.ws.rs.POST;

import com.Test.Exchange.*; // Here class UserInfo is defined

@Path("/ps")
public class TestService {
    private UserInfo ui;
    public TestService () throws IOException {
        ui = new UserInfo();
    }
    public TestService (String uid) throws IOException {
        UserInfo ui = ObjectFileStore.serializeDataIn(uid);
    }

    public TestService (UserInfo ui) throws IOException {
        this.ui = ui;
        ObjectFileStore.serializeDataOut(ui);
    }

    @GET
    @Produces(MediaType.TEXT_HTML)
    public String sayHelloHTML(@QueryParam("uid") String uid) {     
        String resource="<h1> Hi '" + uid + "'. </h1>";
        return resource;
    }

    @POST
    @Consumes(MediaType.APPLICATION_JSON)
    @Produces(MediaType.APPLICATION_JSON)
    public UserInfo postNK(@QueryParam("asid") String asid, UserInfo u) {
        return ui;
    }
}

这是maven依赖项：

<dependency>
  <groupId>org.glassfish.jersey.containers</groupId>
  <artifactId>jersey-container-servlet-core</artifactId>
  <version>${version.jersey}</version>
</dependency>

<dependency>
  <groupId>org.glassfish.jersey.inject</groupId>
  <artifactId>jersey-hk2</artifactId>
  <version>${version.jersey}</version>
</dependency>

<!--  JSON Support (MOXy) -->
<dependency>
  <groupId>org.glassfish.jersey.media</groupId>
  <artifactId>jersey-media-moxy</artifactId>
  <version>${version.jersey}</version>
</dependency>

最后，这是我的web.xml文件：

  <display-name>Test-PS</display-name>
  <welcome-file-list>
    <welcome-file>index.html</welcome-file>
  </welcome-file-list>

  <servlet>
    <servlet-name>Test-PS</servlet-name>
    <servlet-class>org.glassfish.jersey.servlet.ServletContainer</servlet-class>

    <init-param>
      <param-name>jersey.config.server.provider.packages</param-name>
      <param-value>com.Test.PS</param-value>
    </init-param>

    <load-on-startup>1</load-on-startup>
  </servlet>

  <servlet-mapping>
    <servlet-name>Test-PS</servlet-name>
    <url-pattern>/rest/*</url-pattern>
  </servlet-mapping>
</web-app>

使用以下代码消耗post方法时出现以下错误：

UserInfo n2k = new UserInfo();  
ClientConfig config = new ClientConfig(MOXyJsonProvider.class);
Client client = ClientBuilder.newClient(config);
String targetUrl = "http://localhost:8081/Test-PS";
WebTarget target = client.target(targetUrl);
Invocation.Builder invocationBuilder = target.path("rest").path("ps").queryParam("asid", ASID).request(MediaType.APPLICATION_JSON);
Response response = invocationBuilder.post(Entity.entity(n2k, MediaType.APPLICATION_JSON));
UserInfo ui = response.readEntity(UserInfo.class);
response.close();
client.close();

在控制台屏幕上，我看到：

org.glassfish.jersey.message.internal.MessageBodyProviderNotFoundException: MessageBodyReader not found for media type=text/html;charset=utf-8, type=class com.Exchange.UserInfo, genericType=class com.Exchange.UserInfo.
org.glassfish.jersey.message.internal.ReaderInterceptorExecutor$TerminalReaderInterceptor.aroundReadFrom(ReaderInterceptorExecutor.java:232)
org.glassfish.jersey.message.internal.ReaderInterceptorExecutor.proceed(ReaderInterceptorExecutor.java:156)
org.glassfish.jersey.message.internal.MessageBodyFactory.readFrom(MessageBodyFactory.java:1091)
org.glassfish.jersey.message.internal.InboundMessageContext.readEntity(InboundMessageContext.java:874)
org.glassfish.jersey.message.internal.InboundMessageContext.readEntity(InboundMessageContext.java:808)
org.glassfish.jersey.client.ClientResponse.readEntity(ClientResponse.java:321)
org.glassfish.jersey.client.InboundJaxrsResponse$1.call(InboundJaxrsResponse.java:115)
org.glassfish.jersey.internal.Errors.process(Errors.java:316)
org.glassfish.jersey.internal.Errors.process(Errors.java:298)
org.glassfish.jersey.internal.Errors.process(Errors.java:229)
org.glassfish.jersey.process.internal.RequestScope.runInScope(RequestScope.java:389)
org.glassfish.jersey.client.InboundJaxrsResponse.runInScopeIfPossible(InboundJaxrsResponse.java:264)
org.glassfish.jersey.client.InboundJaxrsResponse.readEntity(InboundJaxrsResponse.java:112)
com.AS.AuthenticatorService.Authenticate(AuthenticatorService.java:79)
org.apache.jsp.JSP.Authenticate_jsp._jspService(Authenticate_jsp.java:128)
org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
javax.servlet.http.HttpServlet.service(HttpServlet.java:741)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:458)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:386)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:330)
javax.servlet.http.HttpServlet.service(HttpServlet.java:741)
org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53)

服务器日志说：“POST / Test-PS / rest / ps？asid = AS1 HTTP / 1.1”500 1081

我已经尝试了很多为这个错误提供的解决方案，但它们没有工作！

我还要补充说，如果POST方法返回一个基本类型，例如String，而不是用户定义的类型，即UserInfo，它可以工作！ UserInfo是一个序列化类，其字段如：用户名，出生日期等。

Answer 1

你正在结合事物。您的GET方法可以使用查询参数，但POST不能。像这样更改你的帖子方法：

@POST("{asid}")
@Consumes(MediaType.APPLICATION_JSON)
@Produces(MediaType.APPLICATION_JSON)
public UserInfo postNK(@PathParam("asid") String asid, UserInfo u) {
    return ui;
}

然后

Invocation.Builder invocationBuilder = target.path("rest").path("ps/" + ASID).request(MediaType.APPLICATION_JSON);

我曾经用jax-rs构建rest api所以我想应该有另一种方法来添加ASID参数。

Answer 2

哦，最后我得到了这个问题。这真的很奇怪。 UserInfo类中有一个名为setUserInfo的方法，它接受相同类类型的参数，如下面的代码所示：

public void setUserInfo(UserInfo ui) {
    this.firstName = ui.getFirstName();
    this.lastName = ui.getFirstName();
    this.dateOfBirth = ui.getDateOfBirth();
    this.homeAddress = ui.getHomeAddress();
}

如果我删除它，一切都很顺利。一旦我重新添加它，我得到了同样的例外。似乎禁止类具有接受其类型参数的方法（如果此类将作为Jersey JSON响应发送）。

我不知道为什么，但这是问题，因为我尝试了几次，并且添加了方法，同样的异常被提出！它可能是一个错误！

你也可以尝试一下