@Test(timeout = 60000) public void testServerListener() throws IOException, InterruptedException { ServerManager serverManager = TEST_UTIL.getHBaseCluster().getMaster().getServerManager(); DummyServerListener listener = new DummyServerListener(); serverManager.registerListener(listener); try { MiniHBaseCluster miniCluster = TEST_UTIL.getMiniHBaseCluster(); // Start a new Region Server miniCluster.startRegionServer(); listener.awaitModifications(1); assertEquals(1, listener.getAddedCount()); assertEquals(0, listener.getRemovedCount()); // Start another Region Server listener.reset(); miniCluster.startRegionServer(); listener.awaitModifications(1); assertEquals(1, listener.getAddedCount()); assertEquals(0, listener.getRemovedCount()); int nrs = miniCluster.getRegionServerThreads().size(); // Stop a Region Server listener.reset(); miniCluster.stopRegionServer(nrs - 1); listener.awaitModifications(1); assertEquals(0, listener.getAddedCount()); assertEquals(1, listener.getRemovedCount()); // Stop another Region Server listener.reset(); miniCluster.stopRegionServer(nrs - 2); listener.awaitModifications(1); assertEquals(0, listener.getAddedCount()); assertEquals(1, listener.getRemovedCount()); } finally { serverManager.unregisterListener(listener); } }