Java tutorial
/* * Copyright (c) 2016 Gridtec. All rights reserved. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package at.gridtec.lambda4j.operator.binary; import at.gridtec.lambda4j.Lambda; import at.gridtec.lambda4j.consumer.ThrowableDoubleConsumer; import at.gridtec.lambda4j.consumer.bi.ThrowableBiDoubleConsumer; import at.gridtec.lambda4j.core.exception.ThrownByFunctionalInterfaceException; import at.gridtec.lambda4j.core.util.ThrowableUtils; import at.gridtec.lambda4j.function.ThrowableDoubleFunction; import at.gridtec.lambda4j.function.ThrowableFunction; import at.gridtec.lambda4j.function.bi.ThrowableBiDoubleFunction; import at.gridtec.lambda4j.function.bi.conversion.ThrowableBiBooleanToDoubleFunction; import at.gridtec.lambda4j.function.bi.conversion.ThrowableBiByteToDoubleFunction; import at.gridtec.lambda4j.function.bi.conversion.ThrowableBiCharToDoubleFunction; import at.gridtec.lambda4j.function.bi.conversion.ThrowableBiDoubleToByteFunction; import at.gridtec.lambda4j.function.bi.conversion.ThrowableBiDoubleToCharFunction; import at.gridtec.lambda4j.function.bi.conversion.ThrowableBiDoubleToFloatFunction; import at.gridtec.lambda4j.function.bi.conversion.ThrowableBiDoubleToIntFunction; import at.gridtec.lambda4j.function.bi.conversion.ThrowableBiDoubleToLongFunction; import at.gridtec.lambda4j.function.bi.conversion.ThrowableBiDoubleToShortFunction; import at.gridtec.lambda4j.function.bi.conversion.ThrowableBiFloatToDoubleFunction; import at.gridtec.lambda4j.function.bi.conversion.ThrowableBiIntToDoubleFunction; import at.gridtec.lambda4j.function.bi.conversion.ThrowableBiLongToDoubleFunction; import at.gridtec.lambda4j.function.bi.conversion.ThrowableBiShortToDoubleFunction; import at.gridtec.lambda4j.function.bi.to.ThrowableToDoubleBiFunction; import at.gridtec.lambda4j.function.conversion.ThrowableBooleanToDoubleFunction; import at.gridtec.lambda4j.function.conversion.ThrowableByteToDoubleFunction; import at.gridtec.lambda4j.function.conversion.ThrowableCharToDoubleFunction; import at.gridtec.lambda4j.function.conversion.ThrowableDoubleToByteFunction; import at.gridtec.lambda4j.function.conversion.ThrowableDoubleToCharFunction; import at.gridtec.lambda4j.function.conversion.ThrowableDoubleToFloatFunction; import at.gridtec.lambda4j.function.conversion.ThrowableDoubleToIntFunction; import at.gridtec.lambda4j.function.conversion.ThrowableDoubleToLongFunction; import at.gridtec.lambda4j.function.conversion.ThrowableDoubleToShortFunction; import at.gridtec.lambda4j.function.conversion.ThrowableFloatToDoubleFunction; import at.gridtec.lambda4j.function.conversion.ThrowableIntToDoubleFunction; import at.gridtec.lambda4j.function.conversion.ThrowableLongToDoubleFunction; import at.gridtec.lambda4j.function.conversion.ThrowableShortToDoubleFunction; import at.gridtec.lambda4j.function.to.ThrowableToDoubleFunction; import at.gridtec.lambda4j.operator.unary.ThrowableDoubleUnaryOperator; import at.gridtec.lambda4j.predicate.ThrowableDoublePredicate; import at.gridtec.lambda4j.predicate.bi.ThrowableBiDoublePredicate; import org.apache.commons.lang3.tuple.Pair; import javax.annotation.Nonnegative; import javax.annotation.Nonnull; import javax.annotation.Nullable; import java.util.Comparator; import java.util.Map; import java.util.Objects; import java.util.concurrent.ConcurrentHashMap; import java.util.function.BinaryOperator; import java.util.function.DoubleBinaryOperator; import java.util.function.Function; /** * Represents an operation that accepts two {@code double}-valued input arguments and produces a * {@code double}-valued result which is able to throw any {@link Throwable}. * This is a primitive specialization of {@link ThrowableBinaryOperator}. * <p> * This is a {@link FunctionalInterface} whose functional method is {@link #applyAsDoubleThrows(double, double)}. * * @param <X> The type of the throwable to be thrown by this operator * @apiNote This is a throwable JDK lambda. * @see ThrowableBinaryOperator */ @SuppressWarnings("unused") @FunctionalInterface public interface ThrowableDoubleBinaryOperator<X extends Throwable> extends Lambda, DoubleBinaryOperator { /** * Constructs a {@link ThrowableDoubleBinaryOperator} based on a lambda expression or a method reference. Thereby * the given lambda expression or method reference is returned on an as-is basis to implicitly transform it to the * desired type. With this method, it is possible to ensure that correct type is used from lambda expression or * method reference. * * @param <X> The type of the throwable to be thrown by this operator * @param expression A lambda expression or (typically) a method reference, e.g. {@code this::method} * @return A {@code ThrowableDoubleBinaryOperator} from given lambda expression or method reference. * @implNote This implementation allows the given argument to be {@code null}, but only if {@code null} given, * {@code null} will be returned. * @see <a href="https://docs.oracle.com/javase/tutorial/java/javaOO/lambdaexpressions.html#syntax">Lambda * Expression</a> * @see <a href="https://docs.oracle.com/javase/tutorial/java/javaOO/methodreferences.html">Method Reference</a> */ static <X extends Throwable> ThrowableDoubleBinaryOperator<X> of( @Nullable final ThrowableDoubleBinaryOperator<X> expression) { return expression; } /** * Calls the given {@link ThrowableDoubleBinaryOperator} with the given arguments and returns its result. * * @param <X> The type of the throwable to be thrown by this operator * @param operator The operator to be called * @param value1 The first argument to the operator * @param value2 The second argument to the operator * @return The result from the given {@code ThrowableDoubleBinaryOperator}. * @throws NullPointerException If given argument is {@code null} * @throws X Any throwable from this operators action */ static <X extends Throwable> double call(@Nonnull final ThrowableDoubleBinaryOperator<? extends X> operator, double value1, double value2) throws X { Objects.requireNonNull(operator); return operator.applyAsDoubleThrows(value1, value2); } /** * Creates a {@link ThrowableDoubleBinaryOperator} which uses the {@code first} parameter of this one as argument * for the given {@link ThrowableDoubleUnaryOperator}. * * @param <X> The type of the throwable to be thrown by this operator * @param operator The operator which accepts the {@code first} parameter of this one * @return Creates a {@code ThrowableDoubleBinaryOperator} which uses the {@code first} parameter of this one as * argument for the given {@code ThrowableDoubleUnaryOperator}. * @throws NullPointerException If given argument is {@code null} */ @Nonnull static <X extends Throwable> ThrowableDoubleBinaryOperator<X> onlyFirst( @Nonnull final ThrowableDoubleUnaryOperator<? extends X> operator) { Objects.requireNonNull(operator); return (value1, value2) -> operator.applyAsDoubleThrows(value1); } /** * Creates a {@link ThrowableDoubleBinaryOperator} which uses the {@code second} parameter of this one as argument * for the given {@link ThrowableDoubleUnaryOperator}. * * @param <X> The type of the throwable to be thrown by this operator * @param operator The operator which accepts the {@code second} parameter of this one * @return Creates a {@code ThrowableDoubleBinaryOperator} which uses the {@code second} parameter of this one as * argument for the given {@code ThrowableDoubleUnaryOperator}. * @throws NullPointerException If given argument is {@code null} */ @Nonnull static <X extends Throwable> ThrowableDoubleBinaryOperator<X> onlySecond( @Nonnull final ThrowableDoubleUnaryOperator<? extends X> operator) { Objects.requireNonNull(operator); return (value1, value2) -> operator.applyAsDoubleThrows(value2); } /** * Creates a {@link ThrowableDoubleBinaryOperator} which always returns a given value. * * @param <X> The type of the throwable to be thrown by this operator * @param ret The return value for the constant * @return A {@code ThrowableDoubleBinaryOperator} which always returns a given value. */ @Nonnull static <X extends Throwable> ThrowableDoubleBinaryOperator<X> constant(double ret) { return (value1, value2) -> ret; } /** * Returns a {@link ThrowableDoubleBinaryOperator} which returns the lesser of two elements according to the * specified {@code Comparator}. * * @param <X> The type of the throwable to be thrown by this operator * @param comparator A {@code Comparator} for comparing the two values * @return A {@code ThrowableDoubleBinaryOperator} which returns the lesser of its operands, according to the * supplied {@code Comparator}. * @throws NullPointerException If given argument is {@code null} * @see BinaryOperator#minBy(Comparator) */ @Nonnull static <X extends Throwable> ThrowableDoubleBinaryOperator<X> minBy( @Nonnull final Comparator<Double> comparator) { Objects.requireNonNull(comparator); return (value1, value2) -> comparator.compare(value1, value2) <= 0 ? value1 : value2; } /** * Returns a {@link ThrowableDoubleBinaryOperator} which returns the greater of two elements according to the * specified {@code Comparator}. * * @param <X> The type of the throwable to be thrown by this operator * @param comparator A {@code Comparator} for comparing the two values * @return A {@code ThrowableDoubleBinaryOperator} which returns the greater of its operands, according to the * supplied {@code Comparator}. * @throws NullPointerException If given argument is {@code null} * @see BinaryOperator#maxBy(Comparator) */ @Nonnull static <X extends Throwable> ThrowableDoubleBinaryOperator<X> maxBy( @Nonnull final Comparator<Double> comparator) { Objects.requireNonNull(comparator); return (value1, value2) -> comparator.compare(value1, value2) >= 0 ? value1 : value2; } /** * Applies this operator to the given arguments. * * @param value1 The first argument to the operator * @param value2 The second argument to the operator * @return The return value from the operator, which is its result. * @throws X Any throwable from this operators action */ double applyAsDoubleThrows(double value1, double value2) throws X; /** * Applies this operator to the given arguments. * * @param value1 The first argument to the operator * @param value2 The second argument to the operator * @return The return value from the operator, which is its result. * @apiNote This method mainly exists to use this {@link ThrowableDoubleBinaryOperator} in JRE specific methods only * accepting {@link DoubleBinaryOperator}. If this operator should be applied, then the {@link * #applyAsDoubleThrows(double, double)} method should be used. * @apiNote Overrides the {@link DoubleBinaryOperator#applyAsDouble(double, double)} method by using a redefinition * as default method. This implementation calls the {@link #applyAsDoubleThrows(double, double)} method of this * function and catches the eventually thrown {@link Throwable} from it. If it is of type {@link RuntimeException} * or {@link Error} it is rethrown as is. Other {@code Throwable} types are wrapped in a {@link * ThrownByFunctionalInterfaceException}. */ @Override default double applyAsDouble(double value1, double value2) { // TODO: Remove commented code below /*try { return this.applyAsDoubleThrows(value1, value2); } catch (RuntimeException | Error e) { throw e; } catch (Throwable throwable) { throw new ThrownByFunctionalInterfaceException(throwable.getMessage(), throwable); }*/ return nest().applyAsDouble(value1, value2); } /** * Applies this operator partially to some arguments of this one, producing a {@link ThrowableDoubleUnaryOperator} * as result. * * @param value1 The first argument to this operator used to partially apply this function * @return A {@code ThrowableDoubleUnaryOperator} that represents this operator partially applied the some * arguments. */ @Nonnull default ThrowableDoubleUnaryOperator<X> papplyAsDoubleThrows(double value1) { return (value2) -> this.applyAsDoubleThrows(value1, value2); } /** * Returns the number of arguments for this operator. * * @return The number of arguments for this operator. * @implSpec The default implementation always returns {@code 2}. */ @Nonnegative default int arity() { return 2; } /** * Returns a composed {@link ThrowableToDoubleBiFunction} that first applies the {@code before} functions to its * input, and then applies this operator to the result. * * @param <A> The type of the argument to the first given function, and of composed function * @param <B> The type of the argument to the second given function, and of composed function * @param before1 The first function to apply before this operator is applied * @param before2 The second function to apply before this operator is applied * @return A composed {@code ThrowableToDoubleBiFunction} that first applies the {@code before} functions to its * input, and then applies this operator to the result. * @throws NullPointerException If given argument is {@code null} * @implSpec The input argument of this method is able to handle every type. */ @Nonnull default <A, B> ThrowableToDoubleBiFunction<A, B, X> compose( @Nonnull final ThrowableToDoubleFunction<? super A, ? extends X> before1, @Nonnull final ThrowableToDoubleFunction<? super B, ? extends X> before2) { Objects.requireNonNull(before1); Objects.requireNonNull(before2); return (a, b) -> applyAsDoubleThrows(before1.applyAsDoubleThrows(a), before2.applyAsDoubleThrows(b)); } /** * Returns a composed {@link ThrowableBiBooleanToDoubleFunction} that first applies the {@code before} functions to * its input, and then applies this operator to the result. This method is just convenience, to provide the ability * to execute an operation which accepts {@code boolean} input, before this primitive operator is executed. * * @param before1 The first function to apply before this operator is applied * @param before2 The second function to apply before this operator is applied * @return A composed {@code ThrowableBiBooleanToDoubleFunction} that first applies the {@code before} functions to * its input, and then applies this operator to the result. * @throws NullPointerException If given argument is {@code null} * @implSpec The input argument of this method is a able to handle primitive values. In this case this is {@code * boolean}. */ @Nonnull default ThrowableBiBooleanToDoubleFunction<X> composeFromBoolean( @Nonnull final ThrowableBooleanToDoubleFunction<? extends X> before1, @Nonnull final ThrowableBooleanToDoubleFunction<? extends X> before2) { Objects.requireNonNull(before1); Objects.requireNonNull(before2); return (value1, value2) -> applyAsDoubleThrows(before1.applyAsDoubleThrows(value1), before2.applyAsDoubleThrows(value2)); } /** * Returns a composed {@link ThrowableBiByteToDoubleFunction} that first applies the {@code before} functions to * its input, and then applies this operator to the result. * This method is just convenience, to provide the ability to execute an operation which accepts {@code byte} input, * before this primitive operator is executed. * * @param before1 The first function to apply before this operator is applied * @param before2 The second function to apply before this operator is applied * @return A composed {@code ThrowableBiByteToDoubleFunction} that first applies the {@code before} functions to its * input, and then applies this operator to the result. * @throws NullPointerException If given argument is {@code null} * @implSpec The input argument of this method is a able to handle primitive values. In this case this is {@code * byte}. */ @Nonnull default ThrowableBiByteToDoubleFunction<X> composeFromByte( @Nonnull final ThrowableByteToDoubleFunction<? extends X> before1, @Nonnull final ThrowableByteToDoubleFunction<? extends X> before2) { Objects.requireNonNull(before1); Objects.requireNonNull(before2); return (value1, value2) -> applyAsDoubleThrows(before1.applyAsDoubleThrows(value1), before2.applyAsDoubleThrows(value2)); } /** * Returns a composed {@link ThrowableBiCharToDoubleFunction} that first applies the {@code before} functions to * its input, and then applies this operator to the result. * This method is just convenience, to provide the ability to execute an operation which accepts {@code char} input, * before this primitive operator is executed. * * @param before1 The first function to apply before this operator is applied * @param before2 The second function to apply before this operator is applied * @return A composed {@code ThrowableBiCharToDoubleFunction} that first applies the {@code before} functions to its * input, and then applies this operator to the result. * @throws NullPointerException If given argument is {@code null} * @implSpec The input argument of this method is a able to handle primitive values. In this case this is {@code * char}. */ @Nonnull default ThrowableBiCharToDoubleFunction<X> composeFromChar( @Nonnull final ThrowableCharToDoubleFunction<? extends X> before1, @Nonnull final ThrowableCharToDoubleFunction<? extends X> before2) { Objects.requireNonNull(before1); Objects.requireNonNull(before2); return (value1, value2) -> applyAsDoubleThrows(before1.applyAsDoubleThrows(value1), before2.applyAsDoubleThrows(value2)); } /** * Returns a composed {@link ThrowableDoubleBinaryOperator} that first applies the {@code before} operators to its * input, and then applies this operator to the result. This method is just convenience, to provide the ability to * execute an operation which accepts {@code double} input, before this primitive operator is executed. * * @param before1 The first operator to apply before this operator is applied * @param before2 The second operator to apply before this operator is applied * @return A composed {@code ThrowableDoubleBinaryOperator} that first applies the {@code before} operators to its * input, and then applies this operator to the result. * @throws NullPointerException If given argument is {@code null} * @implSpec The input argument of this method is a able to handle primitive values. In this case this is {@code * double}. */ @Nonnull default ThrowableDoubleBinaryOperator<X> composeFromDouble( @Nonnull final ThrowableDoubleUnaryOperator<? extends X> before1, @Nonnull final ThrowableDoubleUnaryOperator<? extends X> before2) { Objects.requireNonNull(before1); Objects.requireNonNull(before2); return (value1, value2) -> applyAsDoubleThrows(before1.applyAsDoubleThrows(value1), before2.applyAsDoubleThrows(value2)); } /** * Returns a composed {@link ThrowableBiFloatToDoubleFunction} that first applies the {@code before} functions to * its input, and then applies this operator to the result. This method is just convenience, to provide the ability * to execute an operation which accepts {@code float} input, before this primitive operator is executed. * * @param before1 The first function to apply before this operator is applied * @param before2 The second function to apply before this operator is applied * @return A composed {@code ThrowableBiFloatToDoubleFunction} that first applies the {@code before} functions to * its input, and then applies this operator to the result. * @throws NullPointerException If given argument is {@code null} * @implSpec The input argument of this method is a able to handle primitive values. In this case this is {@code * float}. */ @Nonnull default ThrowableBiFloatToDoubleFunction<X> composeFromFloat( @Nonnull final ThrowableFloatToDoubleFunction<? extends X> before1, @Nonnull final ThrowableFloatToDoubleFunction<? extends X> before2) { Objects.requireNonNull(before1); Objects.requireNonNull(before2); return (value1, value2) -> applyAsDoubleThrows(before1.applyAsDoubleThrows(value1), before2.applyAsDoubleThrows(value2)); } /** * Returns a composed {@link ThrowableBiIntToDoubleFunction} that first applies the {@code before} functions to * its input, and then applies this operator to the result. * This method is just convenience, to provide the ability to execute an operation which accepts {@code int} input, * before this primitive operator is executed. * * @param before1 The first function to apply before this operator is applied * @param before2 The second function to apply before this operator is applied * @return A composed {@code ThrowableBiIntToDoubleFunction} that first applies the {@code before} functions to its * input, and then applies this operator to the result. * @throws NullPointerException If given argument is {@code null} * @implSpec The input argument of this method is a able to handle primitive values. In this case this is {@code * int}. */ @Nonnull default ThrowableBiIntToDoubleFunction<X> composeFromInt( @Nonnull final ThrowableIntToDoubleFunction<? extends X> before1, @Nonnull final ThrowableIntToDoubleFunction<? extends X> before2) { Objects.requireNonNull(before1); Objects.requireNonNull(before2); return (value1, value2) -> applyAsDoubleThrows(before1.applyAsDoubleThrows(value1), before2.applyAsDoubleThrows(value2)); } /** * Returns a composed {@link ThrowableBiLongToDoubleFunction} that first applies the {@code before} functions to * its input, and then applies this operator to the result. * This method is just convenience, to provide the ability to execute an operation which accepts {@code long} input, * before this primitive operator is executed. * * @param before1 The first function to apply before this operator is applied * @param before2 The second function to apply before this operator is applied * @return A composed {@code ThrowableBiLongToDoubleFunction} that first applies the {@code before} functions to its * input, and then applies this operator to the result. * @throws NullPointerException If given argument is {@code null} * @implSpec The input argument of this method is a able to handle primitive values. In this case this is {@code * long}. */ @Nonnull default ThrowableBiLongToDoubleFunction<X> composeFromLong( @Nonnull final ThrowableLongToDoubleFunction<? extends X> before1, @Nonnull final ThrowableLongToDoubleFunction<? extends X> before2) { Objects.requireNonNull(before1); Objects.requireNonNull(before2); return (value1, value2) -> applyAsDoubleThrows(before1.applyAsDoubleThrows(value1), before2.applyAsDoubleThrows(value2)); } /** * Returns a composed {@link ThrowableBiShortToDoubleFunction} that first applies the {@code before} functions to * its input, and then applies this operator to the result. This method is just convenience, to provide the ability * to execute an operation which accepts {@code short} input, before this primitive operator is executed. * * @param before1 The first function to apply before this operator is applied * @param before2 The second function to apply before this operator is applied * @return A composed {@code ThrowableBiShortToDoubleFunction} that first applies the {@code before} functions to * its input, and then applies this operator to the result. * @throws NullPointerException If given argument is {@code null} * @implSpec The input argument of this method is a able to handle primitive values. In this case this is {@code * short}. */ @Nonnull default ThrowableBiShortToDoubleFunction<X> composeFromShort( @Nonnull final ThrowableShortToDoubleFunction<? extends X> before1, @Nonnull final ThrowableShortToDoubleFunction<? extends X> before2) { Objects.requireNonNull(before1); Objects.requireNonNull(before2); return (value1, value2) -> applyAsDoubleThrows(before1.applyAsDoubleThrows(value1), before2.applyAsDoubleThrows(value2)); } /** * Returns a composed {@link ThrowableBiDoubleFunction} that first applies this operator to its input, and then * applies the {@code after} function to the result. * * @param <S> The type of return value from the {@code after} function, and of the composed function * @param after The function to apply after this operator is applied * @return A composed {@code ThrowableBiDoubleFunction} that first applies this operator to its input, and then * applies the {@code after} function to the result. * @throws NullPointerException If given argument is {@code null} * @implSpec The input argument of this method is able to return every type. */ @Nonnull default <S> ThrowableBiDoubleFunction<S, X> andThen( @Nonnull final ThrowableDoubleFunction<? extends S, ? extends X> after) { Objects.requireNonNull(after); return (value1, value2) -> after.applyThrows(applyAsDoubleThrows(value1, value2)); } /** * Returns a composed {@link ThrowableBiDoublePredicate} that first applies this operator to its input, and then * applies the {@code after} predicate to the result. This method is just convenience, to provide the ability to * transform this primitive operator to an operation returning {@code boolean}. * * @param after The predicate to apply after this operator is applied * @return A composed {@code ThrowableBiDoublePredicate} that first applies this operator to its input, and then * applies the {@code after} predicate to the result. * @throws NullPointerException If given argument is {@code null} * @implSpec The input argument of this method is a able to return primitive values. In this case this is {@code * boolean}. */ @Nonnull default ThrowableBiDoublePredicate<X> andThenToBoolean( @Nonnull final ThrowableDoublePredicate<? extends X> after) { Objects.requireNonNull(after); return (value1, value2) -> after.testThrows(applyAsDoubleThrows(value1, value2)); } /** * Returns a composed {@link ThrowableBiDoubleToByteFunction} that first applies this operator to its input, and * then applies the {@code after} function to the result. This method is just convenience, to provide the ability to * transform this primitive operator to an operation returning {@code byte}. * * @param after The function to apply after this operator is applied * @return A composed {@code ThrowableBiDoubleToByteFunction} that first applies this operator to its input, and * then applies the {@code after} function to the result. * @throws NullPointerException If given argument is {@code null} * @implSpec The input argument of this method is a able to return primitive values. In this case this is {@code * byte}. */ @Nonnull default ThrowableBiDoubleToByteFunction<X> andThenToByte( @Nonnull final ThrowableDoubleToByteFunction<? extends X> after) { Objects.requireNonNull(after); return (value1, value2) -> after.applyAsByteThrows(applyAsDoubleThrows(value1, value2)); } /** * Returns a composed {@link ThrowableBiDoubleToCharFunction} that first applies this operator to its input, and * then applies the {@code after} function to the result. This method is just convenience, to provide the ability to * transform this primitive operator to an operation returning {@code char}. * * @param after The function to apply after this operator is applied * @return A composed {@code ThrowableBiDoubleToCharFunction} that first applies this operator to its input, and * then applies the {@code after} function to the result. * @throws NullPointerException If given argument is {@code null} * @implSpec The input argument of this method is a able to return primitive values. In this case this is {@code * char}. */ @Nonnull default ThrowableBiDoubleToCharFunction<X> andThenToChar( @Nonnull final ThrowableDoubleToCharFunction<? extends X> after) { Objects.requireNonNull(after); return (value1, value2) -> after.applyAsCharThrows(applyAsDoubleThrows(value1, value2)); } /** * Returns a composed {@link ThrowableDoubleBinaryOperator} that first applies this operator to its input, and then * applies the {@code after} operator to the result. This method is just convenience, to provide the ability to * transform this primitive operator to an operation returning {@code double}. * * @param after The operator to apply after this operator is applied * @return A composed {@code ThrowableDoubleBinaryOperator} that first applies this operator to its input, and then * applies the {@code after} operator to the result. * @throws NullPointerException If given argument is {@code null} * @implSpec The input argument of this method is a able to return primitive values. In this case this is {@code * double}. */ @Nonnull default ThrowableDoubleBinaryOperator<X> andThenToDouble( @Nonnull final ThrowableDoubleUnaryOperator<? extends X> after) { Objects.requireNonNull(after); return (value1, value2) -> after.applyAsDoubleThrows(applyAsDoubleThrows(value1, value2)); } /** * Returns a composed {@link ThrowableBiDoubleToFloatFunction} that first applies this operator to its input, and * then applies the {@code after} function to the result. This method is just convenience, to provide the ability to * transform this primitive operator to an operation returning {@code float}. * * @param after The function to apply after this operator is applied * @return A composed {@code ThrowableBiDoubleToFloatFunction} that first applies this operator to its input, and * then applies the {@code after} function to the result. * @throws NullPointerException If given argument is {@code null} * @implSpec The input argument of this method is a able to return primitive values. In this case this is {@code * float}. */ @Nonnull default ThrowableBiDoubleToFloatFunction<X> andThenToFloat( @Nonnull final ThrowableDoubleToFloatFunction<? extends X> after) { Objects.requireNonNull(after); return (value1, value2) -> after.applyAsFloatThrows(applyAsDoubleThrows(value1, value2)); } /** * Returns a composed {@link ThrowableBiDoubleToIntFunction} that first applies this operator to its input, and then * applies the {@code after} function to the result. This method is just convenience, to provide the ability to * transform this primitive operator to an operation returning {@code int}. * * @param after The function to apply after this operator is applied * @return A composed {@code ThrowableBiDoubleToIntFunction} that first applies this operator to its input, and then * applies the {@code after} function to the result. * @throws NullPointerException If given argument is {@code null} * @implSpec The input argument of this method is a able to return primitive values. In this case this is {@code * int}. */ @Nonnull default ThrowableBiDoubleToIntFunction<X> andThenToInt( @Nonnull final ThrowableDoubleToIntFunction<? extends X> after) { Objects.requireNonNull(after); return (value1, value2) -> after.applyAsIntThrows(applyAsDoubleThrows(value1, value2)); } /** * Returns a composed {@link ThrowableBiDoubleToLongFunction} that first applies this operator to its input, and * then applies the {@code after} function to the result. This method is just convenience, to provide the ability to * transform this primitive operator to an operation returning {@code long}. * * @param after The function to apply after this operator is applied * @return A composed {@code ThrowableBiDoubleToLongFunction} that first applies this operator to its input, and * then applies the {@code after} function to the result. * @throws NullPointerException If given argument is {@code null} * @implSpec The input argument of this method is a able to return primitive values. In this case this is {@code * long}. */ @Nonnull default ThrowableBiDoubleToLongFunction<X> andThenToLong( @Nonnull final ThrowableDoubleToLongFunction<? extends X> after) { Objects.requireNonNull(after); return (value1, value2) -> after.applyAsLongThrows(applyAsDoubleThrows(value1, value2)); } /** * Returns a composed {@link ThrowableBiDoubleToShortFunction} that first applies this operator to its input, and * then applies the {@code after} function to the result. This method is just convenience, to provide the ability to * transform this primitive operator to an operation returning {@code short}. * * @param after The function to apply after this operator is applied * @return A composed {@code ThrowableBiDoubleToShortFunction} that first applies this operator to its input, and * then applies the {@code after} function to the result. * @throws NullPointerException If given argument is {@code null} * @implSpec The input argument of this method is a able to return primitive values. In this case this is {@code * short}. */ @Nonnull default ThrowableBiDoubleToShortFunction<X> andThenToShort( @Nonnull final ThrowableDoubleToShortFunction<? extends X> after) { Objects.requireNonNull(after); return (value1, value2) -> after.applyAsShortThrows(applyAsDoubleThrows(value1, value2)); } /** * Returns a composed {@link ThrowableBiDoubleConsumer} that fist applies this operator to its input, and then * consumes the result using the given {@link ThrowableDoubleConsumer}. * * @param consumer The operation which consumes the result from this operation * @return A composed {@code ThrowableBiDoubleConsumer} that first applies this operator to its input, and then * consumes the result using the given {@code ThrowableDoubleConsumer}. * @throws NullPointerException If given argument is {@code null} */ @Nonnull default ThrowableBiDoubleConsumer<X> consume(@Nonnull final ThrowableDoubleConsumer<? extends X> consumer) { Objects.requireNonNull(consumer); return (value1, value2) -> consumer.acceptThrows(applyAsDoubleThrows(value1, value2)); } /** * Returns a memoized (caching) version of this {@link ThrowableDoubleBinaryOperator}. Whenever it is called, the * mapping between the input parameters and the return value is preserved in a cache, making subsequent calls * returning the memoized value instead of computing the return value again. * <p> * Unless the operator and therefore the used cache will be garbage-collected, it will keep all memoized values * forever. * * @return A memoized (caching) version of this {@code ThrowableDoubleBinaryOperator}. * @implSpec This implementation does not allow the input parameters or return value to be {@code null} for the * resulting memoized operator, as the cache used internally does not permit {@code null} keys or values. * @implNote The returned memoized operator can be safely used concurrently from multiple threads which makes it * thread-safe. */ @Nonnull default ThrowableDoubleBinaryOperator<X> memoized() { if (isMemoized()) { return this; } else { final Map<Pair<Double, Double>, Double> cache = new ConcurrentHashMap<>(); final Object lock = new Object(); return (ThrowableDoubleBinaryOperator<X> & Memoized) (value1, value2) -> { final double returnValue; synchronized (lock) { returnValue = cache.computeIfAbsent(Pair.of(value1, value2), ThrowableFunction.of(key -> applyAsDoubleThrows(key.getLeft(), key.getRight()))); } return returnValue; }; } } /** * Returns a composed {@link ThrowableBinaryOperator} which represents this {@link ThrowableDoubleBinaryOperator}. * Thereby the primitive input argument for this operator is autoboxed. This method provides the possibility to use * this {@code ThrowableDoubleBinaryOperator} with methods provided by the {@code JDK}. * * @return A composed {@code ThrowableBinaryOperator} which represents this {@code ThrowableDoubleBinaryOperator}. */ @Nonnull default ThrowableBinaryOperator<Double, X> boxed() { return this::applyAsDoubleThrows; } /** * Returns a composed {@link DoubleBinaryOperator2} that applies this operator to its input and nests the thrown * {@link Throwable} from it. The {@code Throwable} is nested (wrapped) in a {@link * ThrownByFunctionalInterfaceException}, which is constructed from the thrown {@code Throwable}s message and the * thrown {@code Throwable} itself. * * @return A composed {@link DoubleBinaryOperator2} that applies this operator to its input and nests the thrown * {@code Throwable} from it. * @implNote If thrown {@code Throwable} is of type {@link Error} it is thrown as-is and thus not nested. * @see #nestWith(Function) * @see ThrownByFunctionalInterfaceException */ @Nonnull default DoubleBinaryOperator2 nest() { return nestWith(throwable -> new ThrownByFunctionalInterfaceException(throwable.getMessage(), throwable)); } /** * Returns a composed {@link DoubleBinaryOperator2} that applies this operator to its input and nests the thrown * {@link Throwable} from it using {@code mapper} operation. Thereby {@code mapper} may modify the thrown {@code * Throwable}, regarding its implementation, and returns it nested (wrapped) in a {@link RuntimeException}. * * @param mapper The operation to map the thrown {@code Throwable} to {@code RuntimeException} * @return A composed {@link DoubleBinaryOperator2} that applies this operator to its input and nests the thrown * {@code Throwable} from it using {@code mapper} operation. * @throws NullPointerException If given argument is {@code null} * @implNote If thrown {@code Throwable} is of type {@link Error} it is thrown as-is and thus not nested. * @see #nest() */ @Nonnull default DoubleBinaryOperator2 nestWith( @Nonnull final Function<? super Throwable, ? extends RuntimeException> mapper) { return recover(throwable -> { throw mapper.apply(throwable); }); } /** * Returns a composed {@link DoubleBinaryOperator2} that applies this operator to its input and sneakily throws the * thrown {@link Throwable} from it, if it is not of type {@link RuntimeException} or {@link Error}. This means that * each throwable thrown from the returned composed operator behaves exactly the same as an <em>unchecked</em> * throwable does. As a result, there is no need to handle the throwable of this operator in the returned composed * operator by either wrapping it in an <em>unchecked</em> throwable or to declare it in the {@code throws} clause, * as it would be done in a non sneaky throwing operator. * <p> * What sneaky throwing simply does, is to fake out the compiler and thus it bypasses the principle of * <em>checked</em> throwables. On the JVM (class file) level, all throwables, checked or not, can be thrown * regardless of the {@code throws} clause of methods, which is why this works at all. * <p> * However, when using this method to get a sneaky throwing operator variant of this throwable operator, the * following advantages, disadvantages and limitations will apply: * <p> * If the calling-code is to handle the sneakily thrown throwable, it is required to add it to the {@code throws} * clause of the method that applies the returned composed operator. The compiler will not force the declaration in * the {@code throws} clause anymore. * <p> * If the calling-code already handles the sneakily thrown throwable, the compiler requires it to be added to the * {@code throws} clause of the method that applies the returned composed operator. If not added, the compiler will * error that the caught throwable is never thrown in the corresponding {@code try} block. * <p> * If the returned composed operator is directly surrounded by a {@code try}-{@code catch} block to catch the * sneakily thrown throwable from it, the compiler will error that the caught throwable is never thrown in the * corresponding {@code try} block. * <p> * In any case, if the throwable is not added to the to the {@code throws} clause of the method that applies the * returned composed operator, the calling-code won't be able to catch the throwable by name. It will bubble and * probably be caught in some {@code catch} statement, catching a base type such as {@code try { ... } * catch(RuntimeException e) { ... }} or {@code try { ... } catch(Exception e) { ... }}, but perhaps this is * intended. * <p> * When the called code never throws the specific throwable that it declares, it should obviously be omitted. For * example: {@code new String(byteArr, "UTF-8") throws UnsupportedEncodingException}, but {@code UTF-8} is * guaranteed by the Java specification to be always present. Here, the {@code throws} declaration is a nuisance and * any solution to silence it with minimal boilerplate is welcome. The throwable should therefore be omitted in the * {@code throws} clause of the method that applies the returned composed operator. * <p> * With all that mentioned, the following example will demonstrate this methods correct use: * <pre>{@code * // when called with illegal value ClassNotFoundException is thrown * public Class<?> sneakyThrowingFunctionalInterface(final String className) throws ClassNotFoundException { * return ThrowableFunction.of(Class::forName) // create the correct throwable functional interface * .sneakyThrow() // create a non-throwable variant which is able to sneaky throw (this method) * .apply(className); // apply non-throwable variant -> may sneaky throw a throwable * } * * // call the the method which surround the sneaky throwing functional interface * public void callingMethod() { * try { * final Class<?> clazz = sneakyThrowingFunctionalInterface("some illegal class name"); * // ... do something with clazz ... * } catch(ClassNotFoundException e) { * // ... do something with e ... * } * } * }</pre> * In conclusion, this somewhat contentious ability should be used carefully, of course, with the advantages, * disadvantages and limitations described above kept in mind. * * @return A composed {@link DoubleBinaryOperator2} that applies this operator to its input and sneakily throws the * thrown {@link Throwable} from it, unless it is of type {@link RuntimeException} or {@link Error}. * @implNote If thrown {@link Throwable} is of type {@link RuntimeException} or {@link Error}, it is thrown as-is * and thus not sneakily thrown. */ @Nonnull default DoubleBinaryOperator2 sneakyThrow() { return (value1, value2) -> { try { return this.applyAsDoubleThrows(value1, value2); } catch (RuntimeException | Error e) { throw e; } catch (Throwable throwable) { throw ThrowableUtils.sneakyThrow(throwable); } }; } /** * Returns a composed {@link DoubleBinaryOperator2} that first applies this operator to its input, and then applies * the {@code recover} operation if a {@link Throwable} is thrown from this one. The {@code recover} operation is * represented by a curried operation which is called with throwable information and same arguments of this * operator. * * @param recover The operation to apply if this operator throws a {@code Throwable} * @return A composed {@link DoubleBinaryOperator2} that first applies this operator to its input, and then applies * the {@code recover} operation if a {@code Throwable} is thrown from this one. * @throws NullPointerException If given argument or the returned enclosing operator is {@code null} * @implSpec The implementation checks that the returned enclosing operator from {@code recover} operation is not * {@code null}. If it is, then a {@link NullPointerException} with appropriate message is thrown. * @implNote If thrown {@code Throwable} is of type {@link Error}, it is thrown as-is and thus not passed to {@code * recover} operation. */ @Nonnull default DoubleBinaryOperator2 recover( @Nonnull final Function<? super Throwable, ? extends DoubleBinaryOperator> recover) { Objects.requireNonNull(recover); return (value1, value2) -> { try { return this.applyAsDoubleThrows(value1, value2); } catch (Error e) { throw e; } catch (Throwable throwable) { final DoubleBinaryOperator operator = recover.apply(throwable); Objects.requireNonNull(operator, () -> "recover returned null for " + throwable.getClass() + ": " + throwable.getMessage()); return operator.applyAsDouble(value1, value2); } }; } }