01: /**
02: * Copyright 2006 Webmedia Group Ltd.
03: *
04: * Licensed under the Apache License, Version 2.0 (the "License");
05: * you may not use this file except in compliance with the License.
06: * You may obtain a copy of the License at
07: *
08: * http://www.apache.org/licenses/LICENSE-2.0
09: *
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: **/package org.araneaframework.backend.list.memorybased.expression.logical;
16:
17: import java.util.Iterator;
18: import org.araneaframework.backend.list.memorybased.Expression;
19: import org.araneaframework.backend.list.memorybased.ExpressionEvaluationException;
20: import org.araneaframework.backend.list.memorybased.expression.MultiExpression;
21: import org.araneaframework.backend.list.memorybased.expression.VariableResolver;
22:
23: /**
24: * Composite AND Expression.
25: */
26: public class AndExpression extends MultiExpression {
27:
28: private static final long serialVersionUID = 1L;
29:
30: /**
31: * Returns Boolean.TRUE if all expressions evaluate to Boolean.TRUE, Boolean.FALSE otherwise.
32: * @return whether all expression evaluated to true
33: */
34: public Object evaluate(VariableResolver resolver)
35: throws ExpressionEvaluationException {
36: if (this .children.size() == 0) {
37: throw new ExpressionEvaluationException(
38: "At least one children must be provided");
39: }
40: for (Iterator i = this .children.iterator(); i.hasNext();) {
41: Expression expr = (Expression) i.next();
42: Boolean value = (Boolean) expr.evaluate(resolver);
43: if (!Boolean.TRUE.equals(value)) {
44: return Boolean.FALSE;
45: }
46: }
47: return Boolean.TRUE;
48: }
49: }
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