    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 *      https://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.io.function;
    019
    020import java.io.IOException;
    021import java.io.UncheckedIOException;
    022import java.util.function.Supplier;
    023
    024/**
    025 * Like {@link Supplier} but throws {@link IOException}.
    026 * <p>
    027 * Using an IOSupplier allows you to compose usage of checked and unchecked exceptions as you best see fit.
    028 * </p>
    029 *
    030 * @param <T> the return type of the operations.
    031 * @since 2.7
    032 */
    033@FunctionalInterface
    034public interface IOSupplier<T> {
    035
    036    /**
    037     * Creates a {@link Supplier} for this instance that throws {@link UncheckedIOException} instead of {@link IOException}.
    038     *
    039     * @return an UncheckedIOException Supplier.
    040     * @since 2.12.0
    041     */
    042    default Supplier<T> asSupplier() {
    043        return this::getUnchecked;
    044    }
    045
    046    /**
    047     * Gets a result.
    048     *
    049     * @return a result.
    050     * @throws IOException if an I/O error occurs.
    051     * @see #getUnchecked()
    052     */
    053    T get() throws IOException;
    054
    055    /**
    056     * Gets a result.
    057     *
    058     * @return a result.
    059     * @throws UncheckedIOException if an I/O error occurs.
    060     * @see #get()
    061     * @since 2.17.0
    062     */
    063    default T getUnchecked() throws UncheckedIOException {
    064        return Uncheck.get(this);
    065    }
    066}