SRVE0199E: OutputStream already obtained on $.getJSON

Question

I am currently working with a combination of Spring 4.0.2 and WAS 7.

I am trying to get a JSON object back from spring servlet. This response is very simple and I do not think my error is the result of any semantic error.

Please note: This code works on Tomcat, so I'm not sure why it wouldn't on WAS... This also only seems to occur when I am trying to receive an object and not a primitive type.

For the sake of completeness the code being executed looks like this:

@RequestMapping(value = "/thingy.json", method = RequestMethod.GET)
public @ResponseBody
ArrayList<Things> getActiveTask() {
    log.debug("Sending active tasks");
    THING thing = THINGFactory.getThing();
    return thing.getThings();
}

and the javascript is as follows

$.getJSON("thingy.json", function(data) {
        //logic
        }
        $("#active").append(toAppend);

    });

Upon execution of this code I receive the following error:

 E com.ibm.ws.webcontainer.servlet.ServletWrapper service SRVE0068E: Uncaught exception created in one of the service methods of the servlet THING in application THING_EAR. Exception created : java.lang.IllegalStateException: SRVE0199E: OutputStream already obtained
    at com.ibm.ws.webcontainer.srt.SRTServletResponse.getWriter(SRTServletResponse.java:742)
    at org.apache.jasper.runtime.JspWriterImpl.initOut(JspWriterImpl.java:201)
    at org.apache.jasper.runtime.JspWriterImpl.flushBuffer(JspWriterImpl.java:189)
    at org.apache.jasper.runtime.PageContextImpl.release(PageContextImpl.java:262)
    at org.apache.jasper.runtime.JspFactoryImpl.internalReleasePageContext(JspFactoryImpl.java:177)
    at org.apache.jasper.runtime.JspFactoryImpl.releasePageContext(JspFactoryImpl.java:144)
    at com.ibm._jsp._general._jspService(_general.java:98)
    at com.ibm.ws.jsp.runtime.HttpJspBase.service(HttpJspBase.java:99)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:831)
    at com.ibm.ws.webcontainer.servlet.ServletWrapper.service(ServletWrapper.java:1657)
    at com.ibm.ws.webcontainer.servlet.ServletWrapper.handleRequest(ServletWrapper.java:939)
    at com.ibm.ws.webcontainer.servlet.ServletWrapper.handleRequest(ServletWrapper.java:502)
    at com.ibm.ws.webcontainer.servlet.ServletWrapperImpl.handleRequest(ServletWrapperImpl.java:181)
    at com.ibm.wsspi.webcontainer.servlet.GenericServletWrapper.handleRequest(GenericServletWrapper.java:121)
    at com.ibm.ws.jsp.webcontainerext.AbstractJSPExtensionServletWrapper.handleRequest(AbstractJSPExtensionServletWrapper.java:259)
    at com.ibm.ws.jsp.webcontainerext.AbstractJSPExtensionProcessor.handleRequest(AbstractJSPExtensionProcessor.java:353)
    at com.ibm.ws.webcontainer.webapp.WebAppRequestDispatcher.forward(WebAppRequestDispatcher.java:372)
    at org.springframework.web.servlet.view.InternalResourceView.renderMergedOutputModel(InternalResourceView.java:209)
    at org.springframework.web.servlet.view.AbstractView.render(AbstractView.java:267)
    at org.springframework.web.servlet.DispatcherServlet.render(DispatcherServlet.java:1225)
    at org.springframework.web.servlet.DispatcherServlet.processDispatchResult(DispatcherServlet.java:1012)
    at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:959)
    at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:876)
    at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:961)
    at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:852)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:718)
    at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:837)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:831)
    at com.ibm.ws.webcontainer.servlet.ServletWrapper.service(ServletWrapper.java:1657)
    at com.ibm.ws.webcontainer.servlet.ServletWrapper.handleRequest(ServletWrapper.java:939)
    at com.ibm.ws.webcontainer.servlet.ServletWrapper.handleRequest(ServletWrapper.java:502)
    at com.ibm.ws.webcontainer.servlet.ServletWrapperImpl.handleRequest(ServletWrapperImpl.java:181)
    at com.ibm.ws.webcontainer.servlet.CacheServletWrapper.handleRequest(CacheServletWrapper.java:91)
    at com.ibm.ws.webcontainer.WebContainer.handleRequest(WebContainer.java:864)
    at com.ibm.ws.webcontainer.WSWebContainer.handleRequest(WSWebContainer.java:1592)
    at com.ibm.ws.webcontainer.channel.WCChannelLink.ready(WCChannelLink.java:186)
    at com.ibm.ws.http.channel.inbound.impl.HttpInboundLink.handleDiscrimination(HttpInboundLink.java:452)
    at com.ibm.ws.http.channel.inbound.impl.HttpInboundLink.handleNewRequest(HttpInboundLink.java:511)
    at com.ibm.ws.http.channel.inbound.impl.HttpInboundLink.processRequest(HttpInboundLink.java:305)
    at com.ibm.ws.http.channel.inbound.impl.HttpICLReadCallback.complete(HttpICLReadCallback.java:83)
    at com.ibm.ws.tcp.channel.impl.AioReadCompletionListener.futureCompleted(AioReadCompletionListener.java:165)
    at com.ibm.io.async.AbstractAsyncFuture.invokeCallback(AbstractAsyncFuture.java:217)
    at com.ibm.io.async.AsyncChannelFuture.fireCompletionActions(AsyncChannelFuture.java:161)
    at com.ibm.io.async.AsyncFuture.completed(AsyncFuture.java:138)
    at com.ibm.io.async.ResultHandler.complete(ResultHandler.java:204)
    at com.ibm.io.async.ResultHandler.runEventProcessingLoop(ResultHandler.java:775)
    at com.ibm.io.async.ResultHandler$2.run(ResultHandler.java:905)
    at com.ibm.ws.util.ThreadPool$Worker.run(ThreadPool.java:1646)

I have tried reset the response buffer as suggested in other posts similar to this one, but that doesn't seem to resolve the issue. For reference below is the code used to reset the buffer

response.resetBUffer();

Please let me know if there is any additional information that could be useful to solving this problem!

Answer 1

Turns out Websphere didn't seem to want to honour the @JsonIgnore annotation I had assigned to specific non-serializable properties of the Thingy object and therefore was executing pieces of code it really shouldn't be as well as reading properties it shouldn't be.