public ApnsServiceBuilder withProxy(Proxy proxy) {
        this.proxy = proxy;
        return this;
    }
Specify the proxy to be used to establish the connections
to Apple Servers

<p>Read the <a href="http://java.sun.com/javase/6/docs/technotes/guides/net/proxies.html">
Java Networking and Proxies</a> guide to understand the
proxies complexity.

@param proxy the proxy object to be used to create connections
@return  this
src/main/java/com/notnoop/apns/ApnsServiceBuilder.java