@Test public void testRegionMerge() throws Exception { String nsp1 = prefix + "_regiontest"; NamespaceDescriptor nspDesc = NamespaceDescriptor.create(nsp1) .addConfiguration(TableNamespaceManager.KEY_MAX_REGIONS, "3") .addConfiguration(TableNamespaceManager.KEY_MAX_TABLES, "2") .build(); ADMIN.createNamespace(nspDesc); final TableName tableTwo = TableName.valueOf(nsp1 + TableName.NAMESPACE_DELIM + "table2"); byte[] columnFamily = Bytes.toBytes("info"); HTableDescriptor tableDescOne = new HTableDescriptor(tableTwo); tableDescOne.addFamily(new HColumnDescriptor(columnFamily)); final int initialRegions = 3; ADMIN.createTable(tableDescOne, Bytes.toBytes("1"), Bytes.toBytes("2000"), initialRegions); Connection connection = ConnectionFactory.createConnection(UTIL.getConfiguration()); try (Table table = connection.getTable(tableTwo)) { UTIL.loadNumericRows(table, Bytes.toBytes("info"), 1000, 1999); } ADMIN.flush(tableTwo); List<HRegionInfo> hris = ADMIN.getTableRegions(tableTwo); Collections.sort(hris); // merge the two regions final Set<String> encodedRegionNamesToMerge = Sets.newHashSet(hris.get(0).getEncodedName(), hris.get(1).getEncodedName()); ADMIN.mergeRegions( hris.get(0).getEncodedNameAsBytes(), hris.get(1).getEncodedNameAsBytes(), false); UTIL.waitFor( 10000, 100, new Waiter.ExplainingPredicate<Exception>() { @Override public boolean evaluate() throws Exception { RegionStates regionStates = UTIL.getMiniHBaseCluster().getMaster().getAssignmentManager().getRegionStates(); for (HRegionInfo hri : ADMIN.getTableRegions(tableTwo)) { if (encodedRegionNamesToMerge.contains(hri.getEncodedName())) { return false; } if (!regionStates.isRegionInState(hri, RegionState.State.OPEN)) { return false; } } return true; } @Override public String explainFailure() throws Exception { RegionStates regionStates = UTIL.getMiniHBaseCluster().getMaster().getAssignmentManager().getRegionStates(); for (HRegionInfo hri : ADMIN.getTableRegions(tableTwo)) { if (encodedRegionNamesToMerge.contains(hri.getEncodedName())) { return hri + " which is expected to be merged is still online"; } if (!regionStates.isRegionInState(hri, RegionState.State.OPEN)) { return hri + " is still in not opened"; } } return "Unknown"; } }); hris = ADMIN.getTableRegions(tableTwo); assertEquals(initialRegions - 1, hris.size()); Collections.sort(hris); final HRegionInfo hriToSplit = hris.get(1); ADMIN.split(tableTwo, Bytes.toBytes("500")); UTIL.waitFor( 10000, 100, new Waiter.ExplainingPredicate<Exception>() { @Override public boolean evaluate() throws Exception { RegionStates regionStates = UTIL.getMiniHBaseCluster().getMaster().getAssignmentManager().getRegionStates(); for (HRegionInfo hri : ADMIN.getTableRegions(tableTwo)) { if (hri.getEncodedName().equals(hriToSplit.getEncodedName())) { return false; } if (!regionStates.isRegionInState(hri, RegionState.State.OPEN)) { return false; } } return true; } @Override public String explainFailure() throws Exception { RegionStates regionStates = UTIL.getMiniHBaseCluster().getMaster().getAssignmentManager().getRegionStates(); for (HRegionInfo hri : ADMIN.getTableRegions(tableTwo)) { if (hri.getEncodedName().equals(hriToSplit.getEncodedName())) { return hriToSplit + " which is expected to be split is still online"; } if (!regionStates.isRegionInState(hri, RegionState.State.OPEN)) { return hri + " is still in not opened"; } } return "Unknown"; } }); hris = ADMIN.getTableRegions(tableTwo); assertEquals(initialRegions, hris.size()); Collections.sort(hris); // fail region merge through Coprocessor hook MiniHBaseCluster cluster = UTIL.getHBaseCluster(); HRegionServer regionServer = cluster.getRegionServer(0); RegionServerCoprocessorHost cpHost = regionServer.getRegionServerCoprocessorHost(); Coprocessor coprocessor = cpHost.findCoprocessor(CPRegionServerObserver.class.getName()); CPRegionServerObserver regionServerObserver = (CPRegionServerObserver) coprocessor; regionServerObserver.failMerge(true); regionServerObserver.triggered = false; ADMIN.mergeRegions( hris.get(1).getEncodedNameAsBytes(), hris.get(2).getEncodedNameAsBytes(), false); regionServerObserver.waitUtilTriggered(); hris = ADMIN.getTableRegions(tableTwo); assertEquals(initialRegions, hris.size()); Collections.sort(hris); // verify that we cannot split HRegionInfo hriToSplit2 = hris.get(1); ADMIN.split( tableTwo, TableInputFormatBase.getSplitKey(hriToSplit2.getStartKey(), hriToSplit2.getEndKey(), true)); Thread.sleep(2000); assertEquals(initialRegions, ADMIN.getTableRegions(tableTwo).size()); }