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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.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.Server;
31  import org.apache.hadoop.hbase.executor.EventType;
32  import org.apache.hadoop.hbase.master.HMaster;
33  import org.apache.hadoop.hbase.master.MasterCoprocessorHost;
34  import org.apache.hadoop.hbase.master.MasterServices;
35  
36  /**
37   * Handles adding a new family to an existing table.
38   */
39  @InterfaceAudience.Private
40  public class TableModifyFamilyHandler extends TableEventHandler {
41    private final HColumnDescriptor familyDesc;
42  
43    public TableModifyFamilyHandler(TableName tableName,
44        HColumnDescriptor familyDesc, Server server,
45        final MasterServices masterServices) {
46      super(EventType.C_M_MODIFY_FAMILY, tableName, server, masterServices);
47      this.familyDesc = familyDesc;
48    }
49  
50    @Override
51    protected void prepareWithTableLock() throws IOException {
52      super.prepareWithTableLock();
53      HTableDescriptor htd = getTableDescriptor().getHTableDescriptor();
54      hasColumnFamily(htd, familyDesc.getName());
55    }
56  
57    @Override
58    protected void handleTableOperation(List<HRegionInfo> regions) throws IOException {
59      MasterCoprocessorHost cpHost = ((HMaster) this.server)
60          .getMasterCoprocessorHost();
61      if (cpHost != null) {
62        cpHost.preModifyColumnHandler(this.tableName, this.familyDesc);
63      }
64      // Update table descriptor
65      this.masterServices.getMasterFileSystem().modifyColumn(tableName, familyDesc);
66      if (cpHost != null) {
67        cpHost.postModifyColumnHandler(this.tableName, this.familyDesc);
68      }
69    }
70  
71    @Override
72    public String toString() {
73      String name = "UnknownServerName";
74      if(server != null && server.getServerName() != null) {
75        name = server.getServerName().toString();
76      }
77      String family = "UnknownFamily";
78      if(familyDesc != null) {
79        family = familyDesc.getNameAsString();
80      }
81      return getClass().getSimpleName() + "-" + name + "-" + getSeqid() +
82          "-" + tableName + "-" + family;
83    }
84  
85  }