Exception in thread "main" java.lang.NoClassDefFoundError: Could not initialize class com.sun.jersey.core.header.MediaTypes

Question

I'm trying to run a jersey client and facing this issue. WS Class: ``` import javax.ws.rs.GET; import javax.ws.rs.Path; import javax.ws.rs.Produces; import javax.ws.rs.QueryParam; import javax.ws.rs.core.MediaType; import javax.ws.rs.core.Response; @Path("/hello") public class HelloWorldService { @GET @Path("/vip") @Produces(MediaType.APPLICATION_JSON) public Response getMsg(@QueryParam("msg") String msg) { String output = "Jersey say : " + msg; return Response.status(200).entity(output).build(); } } ``` Client Class: ``` import com.sun.jersey.api.client.Client; import com.sun.jersey.api.client.ClientResponse; import com.sun.jersey.api.client.WebResource; public class JerseyClientGet { public static void main(String[] args) { try { Client client = Client.create(); WebResource webResource = client .resource("http://localhost:8080/TestRest/rest/hello/vip?msg=ABCD"); ClientResponse response = webResource.accept("application/json") .get(ClientResponse.class); if (response.getStatus() != 2…

Accepted Answer

Generally you would get this problem when your code compiled against jersey-bundle-1.8.jar and jsr311-api-0.9.jar. But here I can see you are using `jsr311-api-1.1.1.jar`. Then next problem would be older jar file would have been loaded by the application/web server. For eg: GlassFish 3.1 one comes with Jersy 1.5( which may take precedence over your libraries).

Ideally you would need to check version of JSR-311 library is loaded (0.9 version of the jsr311-api jar is obsolete) in the server. And you should compile against jersey-bundle-1.8.jar, and run with jersey-bundle-1.8.jar and jsr311-api-1.1.1.jar

Exception in thread "main" java.lang.NoClassDefFoundError: Could not initialize class com.sun.jersey.core.header.MediaTypes

Solution

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