    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
    018package org.apache.commons.lang3.function;
    019
    020import java.util.function.DoubleToIntFunction;
    021
    022/**
    023 * A functional interface like {@link DoubleToIntFunction} that declares a {@link Throwable}.
    024 *
    025 * @param <E> The kind of thrown exception or error.
    026 * @since 3.11
    027 */
    028@FunctionalInterface
    029public interface FailableDoubleToIntFunction<E extends Throwable> {
    030
    031    /** NOP singleton */
    032    @SuppressWarnings("rawtypes")
    033    FailableDoubleToIntFunction NOP = t -> 0;
    034
    035    /**
    036     * Returns The NOP singleton.
    037     *
    038     * @param <E> The kind of thrown exception or error.
    039     * @return The NOP singleton.
    040     */
    041    @SuppressWarnings("unchecked")
    042    static <E extends Throwable> FailableDoubleToIntFunction<E> nop() {
    043        return NOP;
    044    }
    045
    046    /**
    047     * Applies this function to the given argument.
    048     *
    049     * @param value the function argument
    050     * @return the function result
    051     * @throws E Thrown when the function fails.
    052     */
    053    int applyAsInt(double value) throws E;
    054}