java - Tomcat with Rest - HTTP Status 500 - Servlet execution threw an exception -

i'm trying code simple restful webservice, following tutorials. i'm searched everywhere can't find solution after several tries fit problem. i'm using netbeans 8.0.2 , apache tomcat 8.0.15 (installed netbeans). i've had several issues tomcat managed solve them, except one.

helloworld.class

package com.example;  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 org.codehaus.jettison.json.jsonexception; import org.codehaus.jettison.json.jsonobject; //path: http://localhost/<appln-folder-name>/hello @path("/hello") public class helloworld {      // http method     @get      // path: http://localhost/<appln-folder-name>/hello/world     @path("/world")      // produces json response     @produces(mediatype.application_json)      public string dohello(){          jsonobject obj = new jsonobject();         try {             obj.put("hello", "world");          } catch (jsonexception e) {             // todo auto-generated catch block         }          system.out.println(obj.tostring());          return obj.tostring();      }  } 

web.xml

<?xml version="1.0" encoding="utf-8"?> <web-app xmlns:xsi="http://www.w3.org/2001/xmlschema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xmlns:web="http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" xsi:schemalocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" id="webapp_id" version="2.5">   <display-name>restful_example</display-name> <!-->project name<-->   <servlet>     <servlet-name>jersey rest service</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>com.example</param-value> <!-->package name<-->     </init-param>     <load-on-startup>1</load-on-startup>   </servlet>   <servlet-mapping>     <servlet-name>jersey rest service</servlet-name>     <url-pattern>/*</url-pattern>   </servlet-mapping> </web-app> 

the error

to test service, followed this: https://netbeans.org/kb/docs/websvc/rest.html#test-rest

what doing wrong?

you have jar conflicts problem. review libs. maybe using jars different jersey versiosn