java - JBoss + RestEasy + Jackson : org. jboss.resteasy.core.ServerResponse 无法转换为 org.jboss.resteasy.specimpl.BuiltResponse

Question

我使用 JBoss (AS 7.1)、RestEasy 和 Jackson 开发 REST Api。 Web 服务返回一个“Account”对象，它是一个简单的 POJO，过去在 JSon 中序列化没有任何问题。

对代码进行一些修改后，服务器在每次调用我的方法后都会弹出异常。执行:

@POST
@Path("/auth")
@Produces(MediaType.APPLICATION_JSON)
public Account authentification(final Account account) throws AuthenticationException {
    Logger.debug(this, "Authenticate");
    Account returnedAccount = // Some authentication code that build a correct Account object
    Logger.debug(this, "Authenticated, return now !");
    return returnedAccount;
}

打印输出如下:

(DEBUG) Authenticate
(DEBUG) Authenticated, return now !
(ERROR) java.lang.ClassCastException: org.jboss.resteasy.core.ServerResponse cannot be cast to org.jboss.resteasy.specimpl.BuiltResponse
    at org.jboss.resteasy.core.ResourceMethodInvoker.invokeOnTarget(ResourceMethodInvoker.java:340)
    at org.jboss.resteasy.core.ResourceMethodInvoker.invoke(ResourceMethodInvoker.java:234)
    at org.jboss.resteasy.core.ResourceMethodInvoker.invoke(ResourceMethodInvoker.java:221)
    at org.jboss.resteasy.core.SynchronousDispatcher.invoke(SynchronousDispatcher.java:356)
    at org.jboss.resteasy.core.SynchronousDispatcher.invoke(SynchronousDispatcher.java:179)
    at org.jboss.resteasy.plugins.server.servlet.ServletContainerDispatcher.service(ServletContainerDispatcher.java:220)
    at org.jboss.resteasy.plugins.server.servlet.HttpServletDispatcher.service(HttpServletDispatcher.java:56)
    at org.jboss.resteasy.plugins.server.servlet.HttpServletDispatcher.service(HttpServletDispatcher.java:51)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:847)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:329)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:248)
    at com.mypackage.filter.MyFilter.doFilter(MyFilter.java:55)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:280)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:248)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:275)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:161)
    at org.jboss.as.jpa.interceptor.WebNonTxEmCloserValve.invoke(WebNonTxEmCloserValve.java:50)
    at org.jboss.as.web.security.SecurityContextAssociationValve.invoke(SecurityContextAssociationValve.java:153)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:155)
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:368)
    at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:877)
    at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:671)
    at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:930)
    at java.lang.Thread.run(Thread.java:662)

我在谷歌上找到的唯一内容是this ticket关于 JBOSS 问题跟踪器，但没有多大帮助。

任何帮助将不胜感激!

Answer 1

要添加到已接受的答案中，如果 Resteasy 公开的方法返回 null，则也会出现此 ClassCastException。例如:

@POST
@Path("getNotices")
@Consumes(MediaType.APPLICATION_JSON)
@Produces(MediaType.APPLICATION_JSON)
GetNoticesResponse getNotices(GetNoticesRequest noticesRequest){
    return null;
}

通过一些幕后逻辑，自定义 Response 对象 (GetNoticesResponse) 将被 org.jboss.resteasy.core.ServerResponse 替换，然后再次转换为自定义响应，从而触发 ClassCastException。