@Evgen you need to decide how the app will communicate with the Solace broker. As Tamimi suggested, MQTT is a good place to start. Once you have your app talking to the broker, you then need to decide how whatever application needs to get the data from the app will talk to the broker. This could be MQTT, JMS or our native Java API.
So, let’s start at the app to broker communication. Use our quick starts to get a broker going first. Then use an MQTT API such as Paho to send messages from your app to the broker.