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.Objects;
23 import java.util.function.BinaryOperator;
24
25 /**
26 * Like {@link BinaryOperator} but throws {@link IOException}.
27 *
28 * @param <T> the type of the operands and result of the operator.
29 *
30 * @see IOBiFunction
31 * @see BinaryOperator
32 * @since 2.12.0
33 */
34 @FunctionalInterface
35 public interface IOBinaryOperator<T> extends IOBiFunction<T, T, T> {
36
37 /**
38 * Creates a {@link IOBinaryOperator} which returns the greater of two elements according to the specified
39 * {@code Comparator}.
40 *
41 * @param <T> the type of the input arguments of the comparator
42 * @param comparator a {@code Comparator} for comparing the two values
43 * @return a {@code BinaryOperator} which returns the greater of its operands, according to the supplied
44 * {@code Comparator}
45 * @throws NullPointerException if the argument is null
46 */
47 static <T> IOBinaryOperator<T> maxBy(final IOComparator<? super T> comparator) {
48 Objects.requireNonNull(comparator);
49 return (a, b) -> comparator.compare(a, b) >= 0 ? a : b;
50 }
51
52 /**
53 * Creates a {@link IOBinaryOperator} which returns the lesser of two elements according to the specified
54 * {@code Comparator}.
55 *
56 * @param <T> the type of the input arguments of the comparator
57 * @param comparator a {@code Comparator} for comparing the two values
58 * @return a {@code BinaryOperator} which returns the lesser of its operands, according to the supplied
59 * {@code Comparator}
60 * @throws NullPointerException if the argument is null
61 */
62 static <T> IOBinaryOperator<T> minBy(final IOComparator<? super T> comparator) {
63 Objects.requireNonNull(comparator);
64 return (a, b) -> comparator.compare(a, b) <= 0 ? a : b;
65 }
66
67 /**
68 * Creates a {@link BinaryOperator} for this instance that throws {@link UncheckedIOException} instead of
69 * {@link IOException}.
70 *
71 * @return an unchecked BiFunction.
72 */
73 default BinaryOperator<T> asBinaryOperator() {
74 return (t, u) -> Uncheck.apply(this, t, u);
75 }
76 }