ThrowingFunction.java

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/*
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 * Copyright 2014-2016 Grzegorz Piwowarek, https://4comprehension.com/
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 *
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 * Licensed under the Apache License, Version 2.0 (the "License");
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 * you may not use this file except in compliance with the License.
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 * You may obtain a copy of the License at
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 *
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 * https://www.apache.org/licenses/LICENSE-2.0
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 *
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 * Unless required by applicable law or agreed to in writing, software
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 * distributed under the License is distributed on an "AS IS" BASIS,
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 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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 * See the License for the specific language governing permissions and
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 * limitations under the License.
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 */
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package com.pivovarit.function;
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import java.util.Optional;
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import java.util.function.Function;
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import static java.util.Objects.requireNonNull;
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/**
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 * Represents a function that accepts one argument and returns a value;
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 * Function might throw a checked exception instance.
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 *
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 * @param <T> the type of the input to the function
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 * @param <R> the type of the result of the function
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 * @param <E> the type of the thrown checked exception
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 * @author Grzegorz Piwowarek
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 */
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@FunctionalInterface
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public interface ThrowingFunction<T, R, E extends Exception> {
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    /**
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     * Applies this function to the given argument.
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     *
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     * @param arg the function argument
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     * @return the function result
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     * @throws E the checked exception type
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     */
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    R apply(T arg) throws E;
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    /**
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     * Returns a new Function instance which returns the result as an Optional, or an empty Optional in case of a thrown exception
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     *
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     * @param <T>      the type of the input to the function
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     * @param <R>      the type of the result of the function
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     * @param function the ThrowingFunction to wrap
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     * @return a Function that returns the result of the given function as an Optional instance.
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     * In case of a failure, empty Optional is returned
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     */
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    static <T, R> Function<T, Optional<R>> lifted(final ThrowingFunction<? super T, ? extends R, ?> function) {
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        requireNonNull(function);
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55 1 1. lifted : replaced return value with null for com/pivovarit/function/ThrowingFunction::lifted → KILLED
 
        return t -> {
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            try {
57 1 1. lambda$lifted$0 : replaced return value with Optional.empty for com/pivovarit/function/ThrowingFunction::lambda$lifted$0 → NO_COVERAGE
 
                return Optional.ofNullable(function.apply(t));
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            } catch (final Exception e) {
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                return Optional.empty();
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            }
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        };
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    }
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    /**
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     * Returns a new Function instance which wraps the thrown checked exception instance into a {@link CheckedException}
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     *
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     * @param <T>      the type of the input to the function
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     * @param <R>      the type of the result of the function
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     * @param function the ThrowingFunction to wrap
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     * @return Function instance that wraps the checked exception into a {@link CheckedException}
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     */
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    static <T, R> Function<T, R> unchecked(final ThrowingFunction<? super T, ? extends R, ?> function) {
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        requireNonNull(function);
74 1 1. unchecked : replaced return value with null for com/pivovarit/function/ThrowingFunction::unchecked → KILLED
 
        return t -> {
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            try {
76 1 1. lambda$unchecked$0 : replaced return value with null for com/pivovarit/function/ThrowingFunction::lambda$unchecked$0 → KILLED
 
                return function.apply(t);
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            } catch (final Exception e) {
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                throw new CheckedException(e);
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            }
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        };
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    }
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    /**
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     * Returns a new Function instance which rethrows the checked exception using the Sneaky Throws pattern
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     *
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     * @param <T1>     the type of the input to the function
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     * @param <R>      the type of the result of the function
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     * @param function the ThrowingFunction to wrap
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     * @return Function instance that rethrows the checked exception using the Sneaky Throws pattern
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     */
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    static <T1, R> Function<T1, R> sneaky(ThrowingFunction<? super T1, ? extends R, ?> function) {
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        requireNonNull(function);
93 1 1. sneaky : replaced return value with null for com/pivovarit/function/ThrowingFunction::sneaky → KILLED
 
        return t -> {
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            try {
95 1 1. lambda$sneaky$0 : replaced return value with null for com/pivovarit/function/ThrowingFunction::lambda$sneaky$0 → NO_COVERAGE
 
                return function.apply(t);
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            } catch (final Exception ex) {
97 1 1. lambda$sneaky$0 : replaced return value with null for com/pivovarit/function/ThrowingFunction::lambda$sneaky$0 → NO_COVERAGE
 
                return SneakyThrowUtil.sneakyThrow(ex);
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            }
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        };
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    }
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    /**
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     * Returns a new Function instance which returns the result as an Optional, or an empty Optional in case of a thrown exception
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     *
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     * @return a Function that returns the result as an Optional instance, or an empty Optional in case of a failure
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     */
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    default Function<T, Optional<R>> lift() {
108 1 1. lift : replaced return value with null for com/pivovarit/function/ThrowingFunction::lift → KILLED
 
        return t -> {
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            try {
110 1 1. lambda$lift$0 : replaced return value with Optional.empty for com/pivovarit/function/ThrowingFunction::lambda$lift$0 → KILLED
 
                return Optional.ofNullable(apply(t));
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            } catch (final Exception e) {
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                return Optional.empty();
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            }
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        };
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    }
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}

Mutations

55

1.1
Location : lifted
Killed by : com.pivovarit.function.ThrowingFunctionTest.[engine:junit-jupiter]/[class:com.pivovarit.function.ThrowingFunctionTest]/[method:shouldWrapInOptionalWhenUsingStandardUtilsFunctions()] replaced return value with null for com/pivovarit/function/ThrowingFunction::lifted → KILLED

57

1.1
Location : lambda$lifted$0
Killed by : none replaced return value with Optional.empty for com/pivovarit/function/ThrowingFunction::lambda$lifted$0 → NO_COVERAGE

74

1.1
Location : unchecked
Killed by : com.pivovarit.function.ThrowingFunctionTest.[engine:junit-jupiter]/[class:com.pivovarit.function.ThrowingFunctionTest]/[method:shouldApplyWhenNoExceptionThrownWithUnchecked()] replaced return value with null for com/pivovarit/function/ThrowingFunction::unchecked → KILLED

76

1.1
Location : lambda$unchecked$0
Killed by : com.pivovarit.function.ThrowingFunctionTest.[engine:junit-jupiter]/[class:com.pivovarit.function.ThrowingFunctionTest]/[method:shouldApplyWhenNoExceptionThrownWithUnchecked()] replaced return value with null for com/pivovarit/function/ThrowingFunction::lambda$unchecked$0 → KILLED

93

1.1
Location : sneaky
Killed by : com.pivovarit.function.ThrowingFunctionTest.[engine:junit-jupiter]/[class:com.pivovarit.function.ThrowingFunctionTest]/[method:shouldSneakyThrow()] replaced return value with null for com/pivovarit/function/ThrowingFunction::sneaky → KILLED

95

1.1
Location : lambda$sneaky$0
Killed by : none replaced return value with null for com/pivovarit/function/ThrowingFunction::lambda$sneaky$0 → NO_COVERAGE

97

1.1
Location : lambda$sneaky$0
Killed by : none replaced return value with null for com/pivovarit/function/ThrowingFunction::lambda$sneaky$0 → NO_COVERAGE

108

1.1
Location : lift
Killed by : com.pivovarit.function.ThrowingFunctionTest.[engine:junit-jupiter]/[class:com.pivovarit.function.ThrowingFunctionTest]/[method:shouldReturnOptional()] replaced return value with null for com/pivovarit/function/ThrowingFunction::lift → KILLED

110

1.1
Location : lambda$lift$0
Killed by : com.pivovarit.function.ThrowingFunctionTest.[engine:junit-jupiter]/[class:com.pivovarit.function.ThrowingFunctionTest]/[method:shouldReturnOptional()] replaced return value with Optional.empty for com/pivovarit/function/ThrowingFunction::lambda$lift$0 → KILLED

Active mutators

Tests examined


Report generated by PIT 1.30.0 support