Using web proxy with Java 8 JAX-RS RESTEasy clients

It seems to be possible to make RESTeasy use Java's proxy properties (e.g. -Dhttp.proxyHost) by using a different engine instead of HttpClient. java.net.HttpURLConnection supports proxy properties out of the box:

ResteasyClient client = new ResteasyClientBuilder().httpEngine(new URLConnectionEngine()).build();

The ResteasyClientBuilder provides a method to define the defaultProxy:

ResteasyClient client = new ResteasyClientBuilder().defaultProxy("localhost", 8080, "http").build();