1 /* 2 * Licensed to the Apache Software Foundation (ASF) under one or more 3 * contributor license agreements. See the NOTICE file distributed with 4 * this work for additional information regarding copyright ownership. 5 * The ASF licenses this file to You under the Apache License, Version 2.0 6 * (the "License"); you may not use this file except in compliance with 7 * the License. You may obtain a copy of the License at 8 * 9 * http://www.apache.org/licenses/LICENSE-2.0 10 * 11 * Unless required by applicable law or agreed to in writing, software 12 * distributed under the License is distributed on an "AS IS" BASIS, 13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 14 * See the License for the specific language governing permissions and 15 * limitations under the License. 16 */ 17 18 package org.apache.commons.io.function; 19 20 import java.io.IOException; 21 import java.io.UncheckedIOException; 22 import java.util.function.UnaryOperator; 23 24 /** 25 * Like {@link UnaryOperator} but throws {@link IOException}. 26 * 27 * @param <T> the type of the operand and result of the operator. 28 * 29 * @see UnaryOperator 30 * @see IOFunction 31 * @since 2.12.0 32 */ 33 @FunctionalInterface 34 public interface IOUnaryOperator<T> extends IOFunction<T, T> { 35 36 /** 37 * Creates a unary operator that always returns its input argument. 38 * 39 * @param <T> the type of the input and output of the operator. 40 * @return a unary operator that always returns its input argument. 41 */ identity()42 static <T> IOUnaryOperator<T> identity() { 43 return t -> t; 44 } 45 46 /** 47 * Creates a {@link UnaryOperator} for this instance that throws {@link UncheckedIOException} instead of 48 * {@link IOException}. 49 * 50 * @return an unchecked BiFunction. 51 */ asUnaryOperator()52 default UnaryOperator<T> asUnaryOperator() { 53 return t -> Uncheck.apply(this, t); 54 } 55 56 } 57