public User getUser(String userId) {
		return userRepository.findOneByUserId(userId);
	}
This class is used as base class for test case,and it will initialize the DB
related config, like datasource, and it will start a transaction for every
test function, and rollback after the execution.
ngrinder-controller/src/test/java/org/ngrinder/AbstractNGrinderTransactionalTest.java