when i add a filter to jersey , then Jersey error about dropwizard-guice

[heldeen]

Deleting that code breaks the binding for HK2 to Guice. You can get the info you need from the javax.ws.rs.container.ContainerRequestContext that is provided in the javax.ws.rs.container.ContainerRequestFilter#filter(ContainerRequestContext) like so:

    @Override
    public void filter(ContainerRequestContext requestContext) throws IOException {
        requestContext.getUriInfo().getBaseUri().getPort();
        requestContext.getUriInfo().getBaseUri().getPath();
    }

The reason it is failing is Jersey is initializing the filter at start time and there is no HTTP Request at that time.

[heldeen]

It has to do w/ how Guice, Guice Servlet, and Jersey2-Guice works vs just plain Jersey/HK2. When the JerseyGuiceUtils.install code is in place the org.glassfish.hk2.api.ServiceLocator that Jersey uses has a preference to satisfy injections from the Guice object graph before the HK2 locator is consulted. The Guice com.google.inject.servlet.ServletModule sets up a provider for javax.servlet.http.HttpServletRequest that is com.google.inject.servlet.RequestScoped and that is why it fails to provide the request object at Jersey startup time; there is no request happening then.

On the other hand if just Jersey/HK2 are involved than the javax.ws.rs.core.@Context annotated javax.servlet.http.HttpServletRequest that HK2 provides for injection is a proxy for a thread local pointer to the current request. The proxy is setup and injected at Jersey startup. As long as that proxy object is only accessed during a request there is no problem.

There are lots of ways to work around it. My earlier suggestion of just using the javax.ws.rs.container.ContainerRequestContext that is provided in the javax.ws.rs.container.ContainerRequestFilter#filter(ContainerRequestContext) is probably the best. The Guice way to get the same functionality as Jersey/HK would be to inject a javax.inject.Provider<javax.servlet.http.HttpServletRequest> instead of the barejavax.servlet.http.HttpServletRequest. Guice can inject a Provider at Jersey startup and as long as the the provider is only asked for the current request during a request there would be no errors.

I would also suggest not mixing JAX-RS and Servlet specs in your filter. Only use the JAX-RS core inside Jersey and only use Servlet inside Jetty.

Hope this helps!

[itgo067]

I find some more infomations for this issue, when i remove this code , working well!

JerseyGuiceUtils.install(new ServiceLocatorGenerator() {
            @Override
            public ServiceLocator create(String name, ServiceLocator parent) {
                if (!name.startsWith("__HK2_Generated_")) {
                    return null;
                }

                return injector.createChildInjector(new JerseyGuiceModule(name)).getInstance(ServiceLocator.class);
            }
        });

[itgo067]

I got it.
But just like me said , why I delete JerseyGuiceUtils.install code. I can use javax.servlet.HttpServletRequest, It will be work fine. can you explain it ? Thanks !

[jhaber]

Thanks for the explanation and the good advice