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1   /**
2    *
3    * Licensed to the Apache Software Foundation (ASF) under one
4    * or more contributor license agreements.  See the NOTICE file
5    * distributed with this work for additional information
6    * regarding copyright ownership.  The ASF licenses this file
7    * to you under the Apache License, Version 2.0 (the
8    * "License"); you may not use this file except in compliance
9    * with the License.  You may obtain a copy of the License at
10   *
11   *     http://www.apache.org/licenses/LICENSE-2.0
12   *
13   * Unless required by applicable law or agreed to in writing, software
14   * distributed under the License is distributed on an "AS IS" BASIS,
15   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
16   * See the License for the specific language governing permissions and
17   * limitations under the License.
18   */
19  package org.apache.hadoop.hbase.master.handler;
20  
21  import java.io.IOException;
22  import java.util.List;
23  
24  import org.apache.hadoop.hbase.classification.InterfaceAudience;
25  import org.apache.hadoop.hbase.TableDescriptor;
26  import org.apache.hadoop.hbase.TableName;
27  import org.apache.hadoop.hbase.HColumnDescriptor;
28  import org.apache.hadoop.hbase.HRegionInfo;
29  import org.apache.hadoop.hbase.HTableDescriptor;
30  import org.apache.hadoop.hbase.InvalidFamilyOperationException;
31  import org.apache.hadoop.hbase.Server;
32  import org.apache.hadoop.hbase.executor.EventType;
33  import org.apache.hadoop.hbase.master.HMaster;
34  import org.apache.hadoop.hbase.master.MasterCoprocessorHost;
35  import org.apache.hadoop.hbase.master.MasterServices;
36  
37  /**
38   * Handles adding a new family to an existing table.
39   */
40  @InterfaceAudience.Private
41  public class TableAddFamilyHandler extends TableEventHandler {
42  
43    private final HColumnDescriptor familyDesc;
44  
45    public TableAddFamilyHandler(TableName tableName, HColumnDescriptor familyDesc,
46        Server server, final MasterServices masterServices) {
47      super(EventType.C_M_ADD_FAMILY, tableName, server, masterServices);
48      this.familyDesc = familyDesc;
49    }
50  
51    @Override
52    protected void prepareWithTableLock() throws IOException {
53      super.prepareWithTableLock();
54      TableDescriptor htd = getTableDescriptor();
55      if (htd.getHTableDescriptor().hasFamily(familyDesc.getName())) {
56        throw new InvalidFamilyOperationException("Family '" +
57          familyDesc.getNameAsString() + "' already exists so cannot be added");
58      }
59    }
60  
61    @Override
62    protected void handleTableOperation(List<HRegionInfo> hris)
63    throws IOException {
64      MasterCoprocessorHost cpHost = ((HMaster) this.server)
65          .getMasterCoprocessorHost();
66      if(cpHost != null){
67        cpHost.preAddColumnHandler(this.tableName, this.familyDesc);
68      }
69      // Update table descriptor
70      this.masterServices.getMasterFileSystem().addColumn(tableName, familyDesc);
71      if(cpHost != null){
72        cpHost.postAddColumnHandler(this.tableName, this.familyDesc);
73      }
74    }
75  
76    @Override
77    public String toString() {
78      String name = "UnknownServerName";
79      if(server != null && server.getServerName() != null) {
80        name = server.getServerName().toString();
81      }
82      String family = "UnknownFamily";
83      if(familyDesc != null) {
84        family = familyDesc.getNameAsString();
85      }
86      return getClass().getSimpleName() + "-" + name + "-" +
87                                getSeqid() + "-" + tableName + "-" + family;
88    }
89  
90  }