ContainerResponseFilter not executed

Question

I want to build a REST-API with Jax-Rs with cors enabled. So I googled how to do and found this:

http://www.developerscrappad.com/1781/java/java-ee/rest-jax-rs/java-ee-7-jax-rs-2-0-cors-on-rest-how-to-make-rest-apis-accessible-from-a-different-domain/

The solution is a ResponseFilter, that adds some header information to every response, so that the browser of the user knows, that cross domain accesses are allowed.

Because the ResponseFilter is not executed when I do any request (tried GET, POST and OPTIONS), I googled again and found this:

ContainerResponseFilter not working

@lefloh gave a good answer, that sounds logic (to remove the annotation @PreMatching). It did so, but nevertheless my filter is not invoked, when I do a Http-Request.

This is my code:

import javax.ws.rs.container.ContainerRequestContext;
import javax.ws.rs.container.ContainerResponseContext;
import javax.ws.rs.container.ContainerResponseFilter;
import javax.ws.rs.ext.Provider;
import java.io.IOException;

@Provider
public class RESTServiceResponseFilter implements ContainerResponseFilter {

    @Override
    public void filter(ContainerRequestContext parContainerRequestContext, ContainerResponseContext parContainerResponseContext) throws IOException {
        parContainerResponseContext.getHeaders().add( "Access-Control-Allow-Origin", "*" );
        parContainerResponseContext.getHeaders().add( "Access-Control-Allow-Credentials", "true" );
        parContainerResponseContext.getHeaders().add( "Access-Control-Allow-Methods", "GET, POST, DELETE, PUT" );
        parContainerResponseContext.getHeaders().add( "Access-Control-Allow-Headers", "Content-Type" );
    }
}

I kept on googling and found out, that I forgot to add the Filter to the web.xml. So I also did that:

<servlet>
    <display-name>webinterface.api</display-name>
    <servlet-name>JAX-RS REST Servlet</servlet-name>
    <servlet-class>com.sun.jersey.spi.container.servlet.ServletContainer</servlet-class>
    <init-param>
        <param-name>com.sun.jersey.config.property.packages</param-name>
        <param-value>de.tsystems.lbus.apprestserver</param-value>
    </init-param>
    <init-param>
        <param-name>com.sun.jersey.spi.container.ContainerResponseFilters</param-name>
        <param-value>de.apprestserver.filter.RESTServiceResponseFilter</param-value>
    </init-param>
    <load-on-startup>1</load-on-startup>
</servlet>

<servlet-mapping>
    <servlet-name>JAX-RS REST Servlet</servlet-name>
    <url-pattern>/TNR/*</url-pattern>
</servlet-mapping>

I have no more ideas now and want to ask you, if you maybe have a solution for me. Thanks in advance!

Answer 1

You're using Jersey 1 (can tell by the com.sun.jersey in your web.xml). The filter implementation you are using (or showing us) is Jersey 2. There's subtle difference, but it's a major difference. The latter will not work with Jersey 1.

And the fact that it even compiles (if that's the case) means that you need to get rid of some dependencies. The class you have is a JAX-RS 2 class (interface). Any JAX-RS/Jersey 2 dependency, you might have, get rid of them. They don't play well (maybe not cause of issue, but get rid of them to drop any confusion)

• Jersey 1 == com.sun.jersey (keep)
• Jersey 2 == org.glassfish.jersey (get rid of)
• JAX-RS 2 api == javax.ws.rs-api (get rid of)

See here for Jersey 1 implementation and configuration