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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.calculation;
22  
23  import org.apache.expreval.client.NullColumnValueException;
24  import org.apache.expreval.client.ResultMissingColumnException;
25  import org.apache.expreval.expr.Operator;
26  import org.apache.expreval.expr.TypeSupport;
27  import org.apache.expreval.expr.node.DateValue;
28  import org.apache.expreval.expr.node.GenericValue;
29  import org.apache.expreval.expr.node.NumberValue;
30  import org.apache.expreval.expr.node.StringValue;
31  import org.apache.hadoop.hbase.hbql.client.HBqlException;
32  import org.apache.hadoop.hbase.hbql.impl.HConnectionImpl;
33  import org.apache.hadoop.hbase.hbql.impl.InvalidTypeException;
34  
35  public class DelegateCalculation extends GenericCalculation {
36  
37      public DelegateCalculation(final GenericValue arg0, final Operator operator, final GenericValue arg1) {
38          super(null, arg0, operator, arg1);
39      }
40  
41      public Class<? extends GenericValue> validateTypes(final GenericValue parentExpr,
42                                                         final boolean allowCollections) throws HBqlException {
43  
44          final Class<? extends GenericValue> type0 = this.getExprArg(0).validateTypes(this, false);
45          final Class<? extends GenericValue> type1 = this.getExprArg(1).validateTypes(this, false);
46  
47          if (TypeSupport.isParentClass(StringValue.class, type0, type1))
48              this.setTypedExpr(new StringCalculation(this.getExprArg(0), this.getOperator(), this.getExprArg(1)));
49          else if (TypeSupport.isParentClass(NumberValue.class, type0, type1))
50              this.setTypedExpr(new NumericCalculation(this.getExprArg(0), this.getOperator(), this.getExprArg(1)));
51          else if (TypeSupport.isParentClass(DateValue.class, type0, type1))
52              this.setTypedExpr(new DateCalculation(this.getExprArg(0), this.getOperator(), this.getExprArg(1)));
53          else
54              throw new InvalidTypeException(this.getInvalidTypeMsg(type0, type1));
55  
56          return this.getTypedExpr().validateTypes(parentExpr, false);
57      }
58  
59      public GenericValue getOptimizedValue() throws HBqlException {
60          this.optimizeAllArgs();
61          return !this.isAConstant() ? this : this.getTypedExpr().getOptimizedValue();
62      }
63  
64      public Object getValue(final HConnectionImpl conn, final Object object) throws HBqlException,
65                                                                                     ResultMissingColumnException,
66                                                                                     NullColumnValueException {
67          return this.getTypedExpr().getValue(conn, object);
68      }
69  }