### Question:
PhaserServiceBarrier implements IServiceBarrier { @Override public int getHoldCount() { return phaser.getUnarrivedParties(); } PhaserServiceBarrier( );  PhaserServiceBarrier( String serviceId ); @Override int hold(); @Override int release(); @Override int getHoldCount(); @Override boolean isAvailable(); @Override int awaitAvailability(); @Override void terminate(); @Override boolean isTerminated();  }### Answer:
@Test public void testGetHoldCount() throws Exception { assertEquals( 0, barrier.getHoldCount() ); barrier.hold(); barrier.hold(); assertEquals( 2, barrier.getHoldCount() ); barrier.release(); assertEquals( 1, barrier.getHoldCount() ); }