@Test(timeout = 60000)
  public void testCreateSameNamespaceTwice() throws Exception {
    final NamespaceDescriptor nsd =
        NamespaceDescriptor.create("testCreateSameNamespaceTwice").build();
    final ProcedureExecutor<MasterProcedureEnv> procExec = getMasterProcedureExecutor();

    long procId1 =
        procExec.submitProcedure(new CreateNamespaceProcedure(procExec.getEnvironment(), nsd));
    // Wait the completion
    ProcedureTestingUtility.waitProcedure(procExec, procId1);
    ProcedureTestingUtility.assertProcNotFailed(procExec, procId1);

    // Create the namespace that exists
    long procId2 =
        procExec.submitProcedure(new CreateNamespaceProcedure(procExec.getEnvironment(), nsd));
    // Wait the completion
    ProcedureTestingUtility.waitProcedure(procExec, procId2);

    // Second create should fail with NamespaceExistException
    ProcedureInfo result = procExec.getResult(procId2);
    assertTrue(result.isFailed());
    LOG.debug("Create namespace failed with exception: " + result.getExceptionFullMessage());
    assertTrue(
        ProcedureTestingUtility.getExceptionCause(result) instanceof NamespaceExistException);
  }
  @Test(timeout = 60000)
  public void testModifyTableDeleteCF() throws Exception {
    final TableName tableName = TableName.valueOf("testModifyTableDeleteCF");
    final String cf1 = "cf1";
    final String cf2 = "cf2";
    final String cf3 = "cf3";
    final ProcedureExecutor<MasterProcedureEnv> procExec = getMasterProcedureExecutor();

    MasterProcedureTestingUtility.createTable(procExec, tableName, null, cf1, cf2, cf3);
    HTableDescriptor currentHtd = UTIL.getAdmin().getTableDescriptor(tableName);
    assertEquals(3, currentHtd.getFamiliesKeys().size());

    // Test 1: Modify the table descriptor
    HTableDescriptor htd = new HTableDescriptor(UTIL.getAdmin().getTableDescriptor(tableName));
    htd.removeFamily(cf2.getBytes());

    long procId =
        ProcedureTestingUtility.submitAndWait(
            procExec, new ModifyTableProcedure(procExec.getEnvironment(), htd));
    ProcedureTestingUtility.assertProcNotFailed(procExec.getResult(procId));

    currentHtd = UTIL.getAdmin().getTableDescriptor(tableName);
    assertEquals(2, currentHtd.getFamiliesKeys().size());
    assertFalse(currentHtd.hasFamily(cf2.getBytes()));

    // Test 2: Modify the table descriptor offline
    UTIL.getAdmin().disableTable(tableName);
    ProcedureTestingUtility.waitNoProcedureRunning(procExec);

    HTableDescriptor htd2 = new HTableDescriptor(UTIL.getAdmin().getTableDescriptor(tableName));
    htd2.removeFamily(cf3.getBytes());
    // Disable Sanity check
    htd2.setConfiguration("hbase.table.sanity.checks", Boolean.FALSE.toString());

    long procId2 =
        ProcedureTestingUtility.submitAndWait(
            procExec, new ModifyTableProcedure(procExec.getEnvironment(), htd2));
    ProcedureTestingUtility.assertProcNotFailed(procExec.getResult(procId2));

    currentHtd = UTIL.getAdmin().getTableDescriptor(tableName);
    assertEquals(1, currentHtd.getFamiliesKeys().size());
    assertFalse(currentHtd.hasFamily(cf3.getBytes()));

    // Removing the last family will fail
    HTableDescriptor htd3 = new HTableDescriptor(UTIL.getAdmin().getTableDescriptor(tableName));
    htd3.removeFamily(cf1.getBytes());
    long procId3 =
        ProcedureTestingUtility.submitAndWait(
            procExec, new ModifyTableProcedure(procExec.getEnvironment(), htd3));
    final ProcedureInfo result = procExec.getResult(procId3);
    assertEquals(true, result.isFailed());
    Throwable cause = ProcedureTestingUtility.getExceptionCause(result);
    assertTrue(
        "expected DoNotRetryIOException, got " + cause, cause instanceof DoNotRetryIOException);
    assertEquals(1, currentHtd.getFamiliesKeys().size());
    assertTrue(currentHtd.hasFamily(cf1.getBytes()));
  }
  @Test(timeout = 60000)
  public void testCreateSystemNamespace() throws Exception {
    final NamespaceDescriptor nsd =
        UTIL.getAdmin().getNamespaceDescriptor(NamespaceDescriptor.SYSTEM_NAMESPACE.getName());
    final ProcedureExecutor<MasterProcedureEnv> procExec = getMasterProcedureExecutor();

    long procId =
        procExec.submitProcedure(new CreateNamespaceProcedure(procExec.getEnvironment(), nsd));
    // Wait the completion
    ProcedureTestingUtility.waitProcedure(procExec, procId);
    ProcedureInfo result = procExec.getResult(procId);
    assertTrue(result.isFailed());
    LOG.debug("Create namespace failed with exception: " + result.getExceptionFullMessage());
    assertTrue(
        ProcedureTestingUtility.getExceptionCause(result) instanceof NamespaceExistException);
  }
  @Test(timeout = 60000)
  public void testCreateNamespaceWithInvalidTableCount() throws Exception {
    final NamespaceDescriptor nsd =
        NamespaceDescriptor.create("testCreateNamespaceWithInvalidTableCount").build();
    final String nsKey = "hbase.namespace.quota.maxtables";
    final String nsValue = "-1";
    final ProcedureExecutor<MasterProcedureEnv> procExec = getMasterProcedureExecutor();

    nsd.setConfiguration(nsKey, nsValue);

    long procId =
        procExec.submitProcedure(new CreateNamespaceProcedure(procExec.getEnvironment(), nsd));
    // Wait the completion
    ProcedureTestingUtility.waitProcedure(procExec, procId);
    ProcedureInfo result = procExec.getResult(procId);
    assertTrue(result.isFailed());
    LOG.debug("Create namespace failed with exception: " + result.getExceptionFullMessage());
    assertTrue(ProcedureTestingUtility.getExceptionCause(result) instanceof ConstraintException);
  }