1 /**
2 * Copyright 2005-2012 The Kuali Foundation
3 *
4 * Licensed under the Educational Community License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.opensource.org/licenses/ecl2.php
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16 package org.kuali.rice.krms.framework.engine.expression;
17
18 import org.kuali.rice.krms.api.engine.ExecutionEnvironment;
19
20 /**
21 * Binary Operator implementation of Expression<Boolean>
22 *
23 * @author Kuali Rice Team (rice.collab@kuali.org)
24 *
25 */
26 public final class BinaryOperatorExpression implements Expression<Boolean> {
27
28 private final ComparisonOperator operator;
29 private final Expression<? extends Object> lhs;
30 private final Expression<? extends Object> rhs;
31
32 /**
33 * Create a BinaryOperatorExpression with the given values
34 * @param operator {@link ComparisonOperator}
35 * @param lhs left hand side Expression
36 * @param rhs right hand side Expression
37 */
38 public BinaryOperatorExpression(ComparisonOperator operator, Expression<? extends Object> lhs, Expression<? extends Object> rhs) {
39 this.operator = operator;
40 this.lhs = lhs;
41 this.rhs = rhs;
42 }
43
44 @Override
45 public Boolean invoke(ExecutionEnvironment environment) {
46 Object lhsValue = lhs.invoke(environment);
47 Object rhsValue = rhs.invoke(environment);
48 return operator.compare(lhsValue, rhsValue);
49 }
50
51 }