Your First JAX-RS Service - RESTful Java with JAX-RS 2.0 - page 39

package package com . restfully . shop . services ;

import import javax.ws.rs.ApplicationPath javax.ws.rs.ApplicationPath ;

import import javax.ws.rs.core.Application javax.ws.rs.core.Application ;

import import java.util.HashSet java.util.HashSet ;

import import java.util.Set java.util.Set ;

@ApplicationPath ( "/services" )
public

public class class ShoppingApplication ShoppingApplication extends extends Application {

private private Set < Object > singletons = new new HashSet < Object >();

private private Set < Class <?>> empty = new new HashSet < Class <?>>();

public public ShoppingApplication () {

singletons . add ( new new CustomerResource ());

}

@Override
public public Set < Class <?>> getClasses () {

return return empty ;

}

@Override
public public Set < Object > getSingletons () {

return

return singletons ;

}

}

The @ApplicationPath defines the relative base URL path for all our JAX-RS services in
the deployment. So, in this example, all of our JAX-RS RESTful services will be prefixed
with the /services path when we execute on them. For our customer service database ex-
ample, we do not have any per-request services, so our ShoppingApplica-
tion.getClasses() method returns an empty set. Our ShoppingApplica-
tion.getSingletons() method returns the Set we initialized in the constructor. This Set
contains an instance of CustomerResource .
In Java EE and standalone servlet deployments, JAX-RS classes must be deployed within the
application server's servlet container as a Web ARchive (WAR). Think of a servlet container
as your application server's web server. A WAR is a JAR file that, in addition to Java class
files, also contains other Java libraries along with dynamic (like JSPs) and static content (like
HTML files or images) that you want to publish on your website. We need to place our Java
classes within this archive so that our application server can deploy them. Here's what the
structure of a WAR file looks like: