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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.expreval.expr;
22  
23  import org.apache.expreval.client.InternalErrorException;
24  import org.apache.expreval.client.NullColumnValueException;
25  import org.apache.expreval.client.ResultMissingColumnException;
26  import org.apache.expreval.expr.literal.BooleanLiteral;
27  import org.apache.expreval.expr.node.BooleanValue;
28  import org.apache.expreval.expr.node.GenericValue;
29  import org.apache.hadoop.hbase.hbql.client.HBqlException;
30  import org.apache.hadoop.hbase.hbql.impl.HConnectionImpl;
31  
32  public class BooleanNot extends GenericExpression implements BooleanValue {
33  
34      private final boolean not;
35  
36      public BooleanNot(final boolean not, final GenericValue arg0) {
37          super(null, arg0);
38          this.not = not;
39      }
40  
41      public Class<? extends GenericValue> validateTypes(final GenericValue parentExpr,
42                                                         final boolean allowCollections) throws HBqlException {
43          this.validateParentClass(BooleanValue.class, this.getExprArg(0).validateTypes(this, false));
44          return BooleanValue.class;
45      }
46  
47      public GenericValue getOptimizedValue() throws HBqlException {
48          this.optimizeAllArgs();
49          if (!this.isAConstant())
50              return this;
51          else
52              try {
53                  return new BooleanLiteral(this.getValue(null, null));
54              }
55              catch (ResultMissingColumnException e) {
56                  throw new InternalErrorException("Missing column: " + e.getMessage());
57              }
58              catch (NullColumnValueException e) {
59                  throw new InternalErrorException("Null value: " + e.getMessage());
60              }
61      }
62  
63      public Boolean getValue(final HConnectionImpl conn, final Object object) throws HBqlException,
64                                                                                      ResultMissingColumnException,
65                                                                                      NullColumnValueException {
66          final boolean retval = (Boolean)this.getExprArg(0).getValue(conn, object);
67          return (this.not) ? !retval : retval;
68      }
69  
70      public String asString() {
71          return (this.not ? "NOT " : "") + this.getExprArg(0).asString();
72      }
73  }