How to return Mocks from Mocks

This shows How to mock our a more complicated api, and trigger events from one system and make sure things happen to another system based on those events. It also demonstrates how to return a mock from a mock which is very useful in testing complex apis such as jdk's nio subsystem. This example consists of three example tests on one system. The files for the test and the system are the following....

TestExample.java - The tests themselves
SysUnderTest.java - The api of the system we are testing
SysUnderTestImpl.java - The system we are testing
TaskRecordService.java - A system we are mocking
TaskSystemService.java - Another system we are mocking
ScheduleListener.java - Part of the api of the TaskSystemService we are mocking
User.java - An interface we will be mocking that TaskRecordService.getUser method returns