event-bus

The main goal of this project is to explore basic features of EventBus from guava.

project description

EventBus allows publish-subscribe-style communication between components without requiring the components to explicitly register with one another (and thus be aware of each other).

Reference: http://www.dmydlarz.com/2017/09/26/event-bus.html
Reference: https://github.com/google/guava/wiki/EventBusExplained

project content

Three types of listeners:

• ListenerOne
• ListenerTwo
• ListenerThree

Three types of events:

• ForAllListenersEvent
• OnlyForListenerOneEvent
• OnlyForListenerTwoAndThreeEvent

Tests for all cases (EventBusTest).

use cases

Using EventBus is quite straightforward:

• Define event classes.
• Define listener classes with methods for specific event classes:

  @Subscribe
  private void general(Event event) {
  
  }
  

• Create EventBus and register appropriate listeners:

  EventBus bus = new EventBus();
  ListenerOne one = new ListenerOne();
  bus.register(one);
  

• Publish events:

  bus.post(event);
  

• If we don't need already registered listener, we simply unregister it:

  EventBus bus = new EventBus();
  ListenerOne one = new ListenerOne();
  bus.register(one);
  ...
  bus.unregister(one);