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 java.io.Serializable;
020import java.util.Objects;
021
022import org.apache.commons.collections4.Predicate;
023
024/**
025 * Predicate implementation that returns true if the input is an instanceof
026 * the type stored in this predicate.
027 *
028 * @since 3.0
029 */
030public final class InstanceofPredicate implements Predicate<Object>, Serializable {
031
032    /** Serial version UID */
033    private static final long serialVersionUID = -6682656911025165584L;
034
035    /**
036     * Factory to create the identity predicate.
037     *
038     * @param type  the type to check for, may not be null
039     * @return the predicate
040     * @throws NullPointerException if the class is null
041     */
042    public static Predicate<Object> instanceOfPredicate(final Class<?> type) {
043        return new InstanceofPredicate(Objects.requireNonNull(type, "type"));
044    }
045
046    /** The type to compare to */
047    private final Class<?> iType;
048
049    /**
050     * Constructor that performs no validation.
051     * Use {@code instanceOfPredicate} if you want that.
052     *
053     * @param type  the type to check for
054     */
055    public InstanceofPredicate(final Class<?> type) {
056        iType = type;
057    }
058
059    /**
060     * Evaluates the predicate returning true if the input object is of the correct type.
061     *
062     * @param object  the input object
063     * @return true if input is of stored type
064     */
065    @Override
066    public boolean evaluate(final Object object) {
067        return iType.isInstance(object);
068    }
069
070    /**
071     * Gets the type to compare to.
072     *
073     * @return the type
074     * @since 3.1
075     */
076    public Class<?> getType() {
077        return iType;
078    }
079
080}