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.functor;
018    
019    /**
020     * A functor that takes one argument and returns an <code>Object</code> value.
021     * <p>
022     * Implementors are encouraged but not required to make their functors
023     * {@link java.io.Serializable Serializable}.
024     * </p>
025     *
026     * @param <A> the argument type.
027     * @param <T> the returned value type.
028     * @since 1.0
029     * @version $Revision: 1156738 $ $Date: 2011-08-11 21:01:15 +0200 (Thu, 11 Aug 2011) $
030     * @author Rodney Waldhoff
031     */
032    public interface UnaryFunction<A, T> extends UnaryFunctor<A> {
033        /**
034         * Evaluate this function.
035         *
036         * @param obj the A object to evaluate
037         * @return the T result of this evaluation
038         */
039        T evaluate(A obj);
040    }