001/*
002 * Licensed to the Apache Software Foundation (ASF) under one
003 * or more contributor license agreements.  See the NOTICE file
004 * distributed with this work for additional information
005 * regarding copyright ownership.  The ASF licenses this file
006 * to you under the Apache License, Version 2.0 (the
007 * "License"); you may not use this file except in compliance
008 * with the License.  You may obtain a copy of the License at
009 *
010 *     http://www.apache.org/licenses/LICENSE-2.0
011 *
012 * Unless required by applicable law or agreed to in writing, software
013 * distributed under the License is distributed on an "AS IS" BASIS,
014 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
015 * See the License for the specific language governing permissions and
016 * limitations under the License.
017 */
018package org.apache.hadoop.hbase.coprocessor;
019
020import java.io.IOException;
021import java.util.Optional;
022import org.apache.hadoop.hbase.TableName;
023import org.apache.hadoop.hbase.client.RegionInfo;
024import org.apache.hadoop.hbase.client.TableDescriptor;
025
026/**
027 * A bad Master Observer to prevent user to create/delete table once.
028 */
029public class BadMasterObserverForCreateDeleteTable implements MasterObserver, MasterCoprocessor {
030  private boolean createFailedOnce = false;
031  private boolean deleteFailedOnce = false;
032
033  @Override
034  public void postCompletedCreateTableAction(ObserverContext<MasterCoprocessorEnvironment> ctx,
035    TableDescriptor desc, RegionInfo[] regions) throws IOException {
036    if (!createFailedOnce && !desc.getTableName().isSystemTable()) {
037      createFailedOnce = true;
038      throw new IOException("execute postCompletedCreateTableAction failed once.");
039    }
040  }
041
042  @Override
043  public void postCompletedDeleteTableAction(ObserverContext<MasterCoprocessorEnvironment> ctx,
044    TableName tableName) throws IOException {
045    if (!deleteFailedOnce && !tableName.isSystemTable()) {
046      deleteFailedOnce = true;
047      throw new IOException("execute postCompletedDeleteTableAction failed once.");
048    }
049  }
050
051  @Override
052  public Optional<MasterObserver> getMasterObserver() {
053    return Optional.of(this);
054  }
055}