问题
I am experimenting with server sent event. Am following this link https://jersey.java.net/documentation/latest/user-guide.html#d0e8376. When I make request to the resource representing Server Sent Event, I get 500 Internal server error.
According to following error, I have to register the body writer for org.glassfish.jersey.media.sse.EventOutput. But, how to do it?
####<21 Nov, 2013 3:17:28 PM IST> <Error> <com.sun.jersey.spi.container.ContainerResponse> <Laptop1> <AdminServer> <[ACTIVE] ExecuteThread: '16' for queue: 'weblogic.kernel.Default (self-tuning)'> <<anonymous>> <> <> <1385027248248> <BEA-000000> <Mapped exception to response: 500 (Internal Server Error)
javax.ws.rs.WebApplicationException: com.sun.jersey.api.MessageException: A message body writer for Java class org.glassfish.jersey.media.sse.EventOutput, and Java type class org.glassfish.jersey.media.sse.EventOutput, and MIME media type text/event-stream was not found
at com.sun.jersey.spi.container.ContainerResponse.write(ContainerResponse.java:285)
at com.sun.jersey.server.impl.application.WebApplicationImpl._handleRequest(WebApplicationImpl.java:1479)
at com.sun.jersey.server.impl.application.WebApplicationImpl.handleRequest(WebApplicationImpl.java:1391)
at com.sun.jersey.server.impl.application.WebApplicationImpl.handleRequest(WebApplicationImpl.java:1381)
at com.sun.jersey.spi.container.servlet.WebComponent.service(WebComponent.java:416)
at com.sun.jersey.spi.container.servlet.ServletContainer.service(ServletContainer.java:538)
at com.sun.jersey.spi.container.servlet.ServletContainer.service(ServletContainer.java:716)
at weblogic.jaxrs.server.portable.servlet.ServletContainer.service(ServletContainer.java:218)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:844)
at weblogic.servlet.internal.StubSecurityHelper$ServletServiceAction.run(StubSecurityHelper.java:280)
at weblogic.servlet.internal.StubSecurityHelper$ServletServiceAction.run(StubSecurityHelper.java:254)
at weblogic.servlet.internal.StubSecurityHelper.invokeServlet(StubSecurityHelper.java:136)
at weblogic.servlet.internal.ServletStubImpl.execute(ServletStubImpl.java:341)
at weblogic.servlet.internal.ServletStubImpl.execute(ServletStubImpl.java:238)
at weblogic.servlet.internal.WebAppServletContext$ServletInvocationAction.wrapRun(WebAppServletContext.java:3363)
at weblogic.servlet.internal.WebAppServletContext$ServletInvocationAction.run(WebAppServletContext.java:3333)
at weblogic.security.acl.internal.AuthenticatedSubject.doAs(AuthenticatedSubject.java:321)
at weblogic.security.service.SecurityManager.runAs(SecurityManager.java:120)
at weblogic.servlet.provider.WlsSubjectHandle.run(WlsSubjectHandle.java:57)
at weblogic.servlet.internal.WebAppServletContext.doSecuredExecute(WebAppServletContext.java:2220)
at weblogic.servlet.internal.WebAppServletContext.securedExecute(WebAppServletContext.java:2146)
at weblogic.servlet.internal.WebAppServletContext.execute(WebAppServletContext.java:2124)
at weblogic.servlet.internal.ServletRequestImpl.run(ServletRequestImpl.java:1564)
at weblogic.servlet.provider.ContainerSupportProviderImpl$WlsRequestExecutor.run(ContainerSupportProviderImpl.java:254)
at weblogic.work.ExecuteThread.execute(ExecuteThread.java:295)
at weblogic.work.ExecuteThread.run(ExecuteThread.java:254)
Caused By: com.sun.jersey.api.MessageException: A message body writer for Java class org.glassfish.jersey.media.sse.EventOutput, and Java type class org.glassfish.jersey.media.sse.EventOutput, and MIME media type text/event-stream was not found
at com.sun.jersey.spi.container.ContainerResponse.write(ContainerResponse.java:285)
at com.sun.jersey.server.impl.application.WebApplicationImpl._handleRequest(WebApplicationImpl.java:1479)
at com.sun.jersey.server.impl.application.WebApplicationImpl.handleRequest(WebApplicationImpl.java:1391)
at com.sun.jersey.server.impl.application.WebApplicationImpl.handleRequest(WebApplicationImpl.java:1381)
at com.sun.jersey.spi.container.servlet.WebComponent.service(WebComponent.java:416)
at com.sun.jersey.spi.container.servlet.ServletContainer.service(ServletContainer.java:538)
at com.sun.jersey.spi.container.servlet.ServletContainer.service(ServletContainer.java:716)
at weblogic.jaxrs.server.portable.servlet.ServletContainer.service(ServletContainer.java:218)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:844)
at weblogic.servlet.internal.StubSecurityHelper$ServletServiceAction.run(StubSecurityHelper.java:280)
at weblogic.servlet.internal.StubSecurityHelper$ServletServiceAction.run(StubSecurityHelper.java:254)
at weblogic.servlet.internal.StubSecurityHelper.invokeServlet(StubSecurityHelper.java:136)
at weblogic.servlet.internal.ServletStubImpl.execute(ServletStubImpl.java:341)
at weblogic.servlet.internal.ServletStubImpl.execute(ServletStubImpl.java:238)
at weblogic.servlet.internal.WebAppServletContext$ServletInvocationAction.wrapRun(WebAppServletContext.java:3363)
at weblogic.servlet.internal.WebAppServletContext$ServletInvocationAction.run(WebAppServletContext.java:3333)
at weblogic.security.acl.internal.AuthenticatedSubject.doAs(AuthenticatedSubject.java:321)
at weblogic.security.service.SecurityManager.runAs(SecurityManager.java:120)
at weblogic.servlet.provider.WlsSubjectHandle.run(WlsSubjectHandle.java:57)
at weblogic.servlet.internal.WebAppServletContext.doSecuredExecute(WebAppServletContext.java:2220)
at weblogic.servlet.internal.WebAppServletContext.securedExecute(WebAppServletContext.java:2146)
at weblogic.servlet.internal.WebAppServletContext.execute(WebAppServletContext.java:2124)
at weblogic.servlet.internal.ServletRequestImpl.run(ServletRequestImpl.java:1564)
at weblogic.servlet.provider.ContainerSupportProviderImpl$WlsRequestExecutor.run(ContainerSupportProviderImpl.java:254)
at weblogic.work.ExecuteThread.execute(ExecuteThread.java:295)
at weblogic.work.ExecuteThread.run(ExecuteThread.java:254)
回答1:
Here is solution for my own question.
To register SseFeature, getSingletons method should be overridden in Application derived class, as show in below code.
@javax.ws.rs.ApplicationPath("webresources")
public class ApplicationConfig extends Application {
//....
@Override
public Set<Object> getSingletons() {
Set<Object> singletons = super.getSingletons();
if(singletons == null){
singletons=new java.util.HashSet<Object>();
}
singletons.add(new SseFeature());
return singletons;
}
//....
}
回答2:
to use jersey latest version ( jersey 2.8 ) we should get rid of com.sun.jersey.api Jersey APIs are now in org.glassfish.jersey package.
I suggest you to go through the following post and resolve the issues check the update in question and comments
NoClassDefFoundError ProcessingException while migrating from jersey 1.x to jersey 2.x ( 2.8 )
来源：https://stackoverflow.com/questions/20117584/server-sent-event-with-jersey-and-weblogic