    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;
    018
    019/**
    020 * Defines a functor interface implemented by classes that create objects.
    021 * <p>
    022 * A {@code Factory} creates an object without using an input parameter.
    023 * If an input parameter is required, then {@link Transformer} is more appropriate.
    024 * </p>
    025 * <p>
    026 * Standard implementations of common factories are provided by
    027 * {@link FactoryUtils}. These include factories that return a constant,
    028 * a copy of a prototype or a new instance.
    029 * </p>
    030 *
    031 * @param <T> the type that the factory creates
    032 *
    033 * @since 2.1
    034 */
    035@FunctionalInterface
    036public interface Factory<T> {
    037
    038    /**
    039     * Create a new object.
    040     *
    041     * @return a new object
    042     * @throws FunctorException (runtime) if the factory cannot create an object
    043     */
    044    T create();
    045
    046}