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1   /*
2    * Copyright (c) 2011.  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.expreval.expr.var;
22  
23  import org.apache.expreval.client.NullColumnValueException;
24  import org.apache.expreval.client.ResultMissingColumnException;
25  import org.apache.expreval.expr.node.StringValue;
26  import org.apache.hadoop.hbase.client.Result;
27  import org.apache.hadoop.hbase.hbql.client.HBqlException;
28  import org.apache.hadoop.hbase.hbql.impl.HConnectionImpl;
29  import org.apache.hadoop.hbase.hbql.mapping.ColumnAttrib;
30  
31  public class KeyColumn extends GenericColumn<StringValue> {
32  
33      public KeyColumn(final ColumnAttrib attrib) {
34          super(attrib);
35      }
36  
37      public Object getValue(final HConnectionImpl conn, final Object object) throws HBqlException,
38                                                                                     ResultMissingColumnException,
39                                                                                     NullColumnValueException {
40          if (this.getExpressionContext().useResultData())
41              return this.getColumnAttrib().getValueFromBytes((Result)object);
42          else
43              return this.getColumnAttrib().getCurrentValue(object);
44      }
45  }