Forward a Phone Call via Voice Proxy with Java

You will use the Spark framework to receive an HTTP call made by Vonage when your number gets a call, adding the necessary dependencies to your build.gradle file, defining the answer route which uses the ConnectAction and PhoneEndpoint classes from the Vonage Java Client Library to create the NCCO response. You need to register the answer route with Spark, purchasing a Vonage number to receive phone calls using the Vonage CLI, exposing your application to the internet safely using ngrok, configuring your Vonage account to link your phone number and application, and testing your application by calling your Vonage number.