I do not know if anyone else has run into this before or not. This is only happening with JSON format. The API works for XML. I am using CXF library. javax.ws.rs.InternalServerErrorException at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:39) at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27) at java.lang.reflect.Constructor.newInstance(Constructor.java:513) at org.apache.cxf.jaxrs.client.AbstractClient.convertToWebApplicationException(AbstractClient.java:461) at org.apache.cxf.jaxrs.client.WebClient.doInvoke(WebClient.java:860) at org.apache.cxf.jaxrs.client.WebClient.doInvoke(WebClient.java:831) at org.apache.cxf.jaxrs.client.WebClient.invoke(WebClient.java:394) at org.apache.cxf.jaxrs.client.WebClient.get(WebClient.java:573)