001    /*
002     *  Licensed to the Apache Software Foundation (ASF) under one or more
003     *  contributor license agreements.  See the NOTICE file distributed with
004     *  this work for additional information regarding copyright ownership.
005     *  The ASF licenses this file to You under the Apache License, Version 2.0
006     *  (the "License"); you may not use this file except in compliance with
007     *  the License.  You may obtain a copy of the License at
008     *
009     *      http://www.apache.org/licenses/LICENSE-2.0
010     *
011     *  Unless required by applicable law or agreed to in writing, software
012     *  distributed under the License is distributed on an "AS IS" BASIS,
013     *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014     *  See the License for the specific language governing permissions and
015     *  limitations under the License.
016     */
017    package org.apache.commons.collections.functors;
018    
019    import java.io.Serializable;
020    import java.util.Collection;
021    
022    import org.apache.commons.collections.Predicate;
023    
024    /**
025     * Predicate implementation that returns true if none of the
026     * predicates return true.
027     * If the array of predicates is empty, then this predicate returns true.
028     * <p>
029     * NOTE: In versions prior to 3.2 an array size of zero or one
030     * threw an exception.
031     *
032     * @since Commons Collections 3.0
033     * @version $Revision: 646777 $ $Date: 2008-04-10 13:33:15 +0100 (Thu, 10 Apr 2008) $
034     *
035     * @author Stephen Colebourne
036     * @author Matt Benson
037     */
038    public final class NonePredicate implements Predicate, PredicateDecorator, Serializable {
039    
040        /** Serial version UID */
041        private static final long serialVersionUID = 2007613066565892961L;
042        
043        /** The array of predicates to call */
044        private final Predicate[] iPredicates;
045        
046        /**
047         * Factory to create the predicate.
048         * <p>
049         * If the array is size zero, the predicate always returns true.
050         *
051         * @param predicates  the predicates to check, cloned, not null
052         * @return the <code>any</code> predicate
053         * @throws IllegalArgumentException if the predicates array is null
054         * @throws IllegalArgumentException if any predicate in the array is null
055         */
056        public static Predicate getInstance(Predicate[] predicates) {
057            FunctorUtils.validate(predicates);
058            if (predicates.length == 0) {
059                return TruePredicate.INSTANCE;
060            }
061            predicates = FunctorUtils.copy(predicates);
062            return new NonePredicate(predicates);
063        }
064    
065        /**
066         * Factory to create the predicate.
067         * <p>
068         * If the collection is size zero, the predicate always returns true.
069         *
070         * @param predicates  the predicates to check, cloned, not null
071         * @return the <code>one</code> predicate
072         * @throws IllegalArgumentException if the predicates array is null
073         * @throws IllegalArgumentException if any predicate in the array is null
074         */
075        public static Predicate getInstance(Collection predicates) {
076            Predicate[] preds = FunctorUtils.validate(predicates);
077            if (preds.length == 0) {
078                return TruePredicate.INSTANCE;
079            }
080            return new NonePredicate(preds);
081        }
082    
083        /**
084         * Constructor that performs no validation.
085         * Use <code>getInstance</code> if you want that.
086         * 
087         * @param predicates  the predicates to check, not cloned, not null
088         */
089        public NonePredicate(Predicate[] predicates) {
090            super();
091            iPredicates = predicates;
092        }
093    
094        /**
095         * Evaluates the predicate returning false if any stored predicate returns false.
096         * 
097         * @param object  the input object
098         * @return true if none of decorated predicates return true
099         */
100        public boolean evaluate(Object object) {
101            for (int i = 0; i < iPredicates.length; i++) {
102                if (iPredicates[i].evaluate(object)) {
103                    return false;
104                }
105            }
106            return true;
107        }
108    
109        /**
110         * Gets the predicates, do not modify the array.
111         * 
112         * @return the predicates
113         * @since Commons Collections 3.1
114         */
115        public Predicate[] getPredicates() {
116            return iPredicates;
117        }
118    
119    }