The ResourceConfig instance does not contain any root resource classes

This is my 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>Web</display-name>
<welcome-file-list>
<welcome-file>index.html</welcome-file>
<welcome-file>index.htm</welcome-file>
<welcome-file>index.jsp</welcome-file>
<welcome-file>default.html</welcome-file>
<welcome-file>default.htm</welcome-file>
<welcome-file>default.jsp</welcome-file>
</welcome-file-list>

<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.jersey.test.service</param-value>//Represents the path to your service side, consistent with your engineering server-side path.
</init-param>
<load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>jersey REST service</servlet-name>
<url-pattern>/rest/*</url-pattern>
</servlet-mapping>
</web-app>