    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 */
    017package org.apache.commons.collections4.functors;
    018
    019import static org.apache.commons.collections4.functors.FunctorUtils.coerce;
    020import static org.apache.commons.collections4.functors.FunctorUtils.validate;
    021import static org.apache.commons.collections4.functors.TruePredicate.truePredicate;
    022
    023import java.util.Collection;
    024
    025import org.apache.commons.collections4.Predicate;
    026
    027/**
    028 * Predicate implementation that returns true if all the
    029 * predicates return true.
    030 * If the array of predicates is empty, then this predicate returns true.
    031 * <p>
    032 * NOTE: In versions prior to 3.2 an array size of zero or one
    033 * threw an exception.
    034 * </p>
    035 *
    036 * @param <T> the type of the input to the predicate.
    037 * @since 3.0
    038 */
    039public final class AllPredicate<T> extends AbstractQuantifierPredicate<T> {
    040
    041    /** Serial version UID */
    042    private static final long serialVersionUID = -3094696765038308799L;
    043
    044    /**
    045     * Creates the predicate.
    046     * <p>
    047     * If the collection is size zero, the predicate always returns true.
    048     * If the collection is size one, then that predicate is returned.
    049     * </p>
    050     *
    051     * @param <T> the type that the predicate queries
    052     * @param predicates  the predicates to check, cloned, not null
    053     * @return the {@code all} predicate
    054     * @throws NullPointerException if the predicates array is null
    055     * @throws NullPointerException if any predicate in the array is null
    056     */
    057    public static <T> Predicate<T> allPredicate(final Collection<? extends Predicate<? super T>> predicates) {
    058        final Predicate<? super T>[] preds = validate(predicates);
    059        if (preds.length == 0) {
    060            return truePredicate();
    061        }
    062        if (preds.length == 1) {
    063            return coerce(preds[0]);
    064        }
    065        return new AllPredicate<>(preds);
    066    }
    067
    068    /**
    069     * Creates the predicate.
    070     * <p>
    071     * If the array is size zero, the predicate always returns true.
    072     * If the array is size one, then that predicate is returned.
    073     * </p>
    074     *
    075     * @param <T> the type that the predicate queries
    076     * @param predicates  the predicates to check, cloned, not null
    077     * @return the {@code all} predicate
    078     * @throws NullPointerException if the predicates array is null
    079     * @throws NullPointerException if any predicate in the array is null
    080     */
    081    public static <T> Predicate<T> allPredicate(final Predicate<? super T>... predicates) {
    082        validate(predicates);
    083        if (predicates.length == 0) {
    084            return truePredicate();
    085        }
    086        if (predicates.length == 1) {
    087            return coerce(predicates[0]);
    088        }
    089        // <T> not needed in Eclipse but needed by the command line compiler
    090        return new AllPredicate<T>(FunctorUtils.copy(predicates));
    091    }
    092
    093    /**
    094     * Constructor that performs no validation.
    095     * Use {@code allPredicate} if you want that.
    096     *
    097     * @param predicates  the predicates to check, not cloned, not null
    098     */
    099    public AllPredicate(final Predicate<? super T>... predicates) {
    100        super(predicates);
    101    }
    102
    103    /**
    104     * Evaluates the predicate returning true if all predicates return true.
    105     *
    106     * @param object  the input object
    107     * @return true if all decorated predicates return true
    108     */
    109    @Override
    110    public boolean test(final T object) {
    111        for (final Predicate<? super T> iPredicate : iPredicates) {
    112            if (!iPredicate.test(object)) {
    113                return false;
    114            }
    115        }
    116        return true;
    117    }
    118
    119}