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1   /*
2    * Copyright (c) 2010.  The Apache Software Foundation
3    *
4    * Licensed to the Apache Software Foundation (ASF) under one
5    * or more contributor license agreements.  See the NOTICE file
6    * distributed with this work for additional information
7    * regarding copyright ownership.  The ASF licenses this file
8    * to you under the Apache License, Version 2.0 (the
9    * "License"); you may not use this file except in compliance
10   * with the License.  You may obtain a copy of the License at
11   *
12   *     http://www.apache.org/licenses/LICENSE-2.0
13   *
14   * Unless required by applicable law or agreed to in writing, software
15   * distributed under the License is distributed on an "AS IS" BASIS,
16   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
17   * See the License for the specific language governing permissions and
18   * limitations under the License.
19   */
20  
21  package org.apache.hadoop.hbase.hbql.statement;
22  
23  import org.apache.hadoop.hbase.HTableDescriptor;
24  import org.apache.hadoop.hbase.client.HBaseAdmin;
25  import org.apache.hadoop.hbase.hbql.client.ExecutionResults;
26  import org.apache.hadoop.hbase.hbql.client.HBqlException;
27  import org.apache.hadoop.hbase.hbql.impl.HConnectionImpl;
28  
29  import java.io.IOException;
30  
31  public class ShowTablesStatement extends GenericStatement implements ConnectionStatement {
32  
33      public ShowTablesStatement() {
34          super(null);
35      }
36  
37      protected ExecutionResults execute(final HConnectionImpl conn) throws HBqlException {
38  
39          try {
40              final HBaseAdmin admin = conn.getHBaseAdmin();
41  
42              final ExecutionResults retval = new ExecutionResults();
43              retval.out.println("Tables: ");
44              for (final HTableDescriptor tableDesc : admin.listTables())
45                  retval.out.println("\t" + tableDesc.getNameAsString());
46  
47              retval.out.flush();
48              return retval;
49          }
50          catch (IOException e) {
51              throw new HBqlException(e);
52          }
53      }
54  
55      public static String usage() {
56          return "SHOW TABLES";
57      }
58  }