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