BiPredicateWithException.java
/**
* Powerunit - A JDK1.8 test framework
* Copyright (C) 2014 Mathieu Boretti.
*
* This file is part of Powerunit
*
* Powerunit is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* Powerunit is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with Powerunit. If not, see <http://www.gnu.org/licenses/>.
*/
package ch.powerunit.extensions.exceptions;
import static ch.powerunit.extensions.exceptions.Constants.verifyExceptionMapper;
import static ch.powerunit.extensions.exceptions.Constants.verifyPredicate;
import static java.util.Objects.requireNonNull;
import java.util.function.BiPredicate;
import java.util.function.Function;
import java.util.function.Supplier;
/**
* Represents a predicate (boolean-valued function) of two arguments that may
* throw exception. This is the two-arity specialization of
* {@link PredicateWithException}.
* <h3>General contract</h3>
* <ul>
* <li><b>{@link #test(Object, Object) boolean test(T t, U u) throws
* E}</b> - The functional method.</li>
* <li><b>uncheck</b> - Return a {@code BiPredicate<T, U>}</li>
* <li><b>lift</b> - Return a {@code BiPredicate<T, U>}</li>
* <li><b>ignore</b> - Return a {@code BiPredicate<T, U>}</li>
* </ul>
*
*
* @see BiPredicate
* @param <T>
* the type of the first argument to the predicate
* @param <U>
* the type of the second argument the predicate
* @param <E>
* the type of the potential exception of the function
*/
@FunctionalInterface
public interface BiPredicateWithException<T, U, E extends Exception>
extends PrimitiveReturnExceptionHandlerSupport<BiPredicate<T, U>, BiPredicateWithException<T, U, E>>,
BooleanDefaultValue {
/**
* Evaluates this predicate on the given arguments.
*
* @param t
* the first input argument
* @param u
* the second input argument
* @return {@code true} if the input arguments match the predicate, otherwise
* {@code false}
* @throws E
* any exception
* @see BiPredicate#test(Object, Object)
*/
boolean test(T t, U u) throws E;
@Override
default BiPredicate<T, U> uncheckOrIgnore(boolean uncheck) {
return (t, u) -> {
try {
return test(t, u);
} catch (Exception e) {
PrimitiveReturnExceptionHandlerSupport.handleException(uncheck, e, exceptionMapper());
return defaultValue();
}
};
}
/**
* Returns a composed predicate that represents a short-circuiting logical AND
* of this predicate and another. When evaluating the composed predicate, if
* this predicate is {@code false}, then the {@code other} predicate is not
* evaluated.
*
* <p>
* Any exceptions thrown during evaluation of either predicate are relayed to
* the caller; if evaluation of this predicate throws an exception, the
* {@code other} predicate will not be evaluated.
*
* @param other
* a predicate that will be logically-ANDed with this predicate
* @return a composed predicate that represents the short-circuiting logical AND
* of this predicate and the {@code other} predicate
* @throws NullPointerException
* if other is null
* @see #or(BiPredicateWithException)
* @see #negate()
*/
default BiPredicateWithException<T, U, E> and(BiPredicateWithException<? super T, ? super U, ? extends E> other) {
requireNonNull(other);
return (t, u) -> test(t, u) && other.test(t, u);
}
/**
* Returns a predicate that represents the logical negation of this predicate.
*
* @return a predicate that represents the logical negation of this predicate
* @see #and(BiPredicateWithException)
* @see #or(BiPredicateWithException)
*/
default BiPredicateWithException<T, U, E> negate() {
return (t, u) -> !test(t, u);
}
/**
* Negate a {@code DoublePredicateWithException}.
*
* @param predicate
* to be negate
* @param <T>
* the type of the first argument to the predicate
* @param <U>
* the type of the second argument the predicate
* @param <E>
* the type of the potential exception
* @return the negated predicate
* @see #negate()
*/
static <T, U, E extends Exception> BiPredicateWithException<T, U, E> negate(
BiPredicateWithException<T, U, E> predicate) {
return verifyPredicate(predicate).negate();
}
/**
* Returns a composed predicate that represents a short-circuiting logical OR of
* this predicate and another. When evaluating the composed predicate, if this
* predicate is {@code true}, then the {@code other} predicate is not evaluated.
*
* <p>
* Any exceptions thrown during evaluation of either predicate are relayed to
* the caller; if evaluation of this predicate throws an exception, the
* {@code other} predicate will not be evaluated.
*
* @param other
* a predicate that will be logically-ORed with this predicate
* @return a composed predicate that represents the short-circuiting logical OR
* of this predicate and the {@code other} predicate
* @throws NullPointerException
* if other is null
* @see #and(BiPredicateWithException)
* @see #negate()
*/
default BiPredicateWithException<T, U, E> or(BiPredicateWithException<? super T, ? super U, ? extends E> other) {
requireNonNull(other);
return (t, u) -> test(t, u) || other.test(t, u);
}
/**
* Returns a predicate that always throw exception.
*
* @param exceptionBuilder
* the supplier to create the exception
* @param <T>
* the type of the first argument to the predicate
* @param <U>
* the type of the second argument the predicate
* @param <E>
* the type of the exception
* @return a predicate that always throw exception
*/
static <T, U, E extends Exception> BiPredicateWithException<T, U, E> failing(Supplier<E> exceptionBuilder) {
return (t, u) -> {
throw exceptionBuilder.get();
};
}
/**
* Converts a {@code BiPredicateWithException} to a {@code BiPredicate} that
* wraps to {@code RuntimeException}.
*
* @param predicate
* to be unchecked
* @param <T>
* the type of the first argument to the predicate
* @param <U>
* the type of the second argument the predicate
* @param <E>
* the type of the potential exception
* @return the unchecked predicate
* @see #uncheck()
* @see #unchecked(BiPredicateWithException, Function)
* @throws NullPointerException
* if predicate is null
*/
static <T, U, E extends Exception> BiPredicate<T, U> unchecked(BiPredicateWithException<T, U, E> predicate) {
return verifyPredicate(predicate).uncheck();
}
/**
* Converts a {@code BiPredicateWithException} to a {@code BiPredicate} that
* wraps to {@code RuntimeException} by using the provided mapping function.
*
* @param predicate
* the be unchecked
* @param exceptionMapper
* a function to convert the exception to the runtime exception.
* @param <T>
* the type of the first argument to the predicate
* @param <U>
* the type of the second argument the predicate
* @param <E>
* the type of the potential exception
* @return the unchecked predicate
* @see #uncheck()
* @see #unchecked(BiPredicateWithException)
* @throws NullPointerException
* if predicate or exceptionMapper is null
*/
static <T, U, E extends Exception> BiPredicate<T, U> unchecked(BiPredicateWithException<T, U, E> predicate,
Function<Exception, RuntimeException> exceptionMapper) {
verifyPredicate(predicate);
verifyExceptionMapper(exceptionMapper);
return new BiPredicateWithException<T, U, E>() {
@Override
public boolean test(T t, U u) throws E {
return predicate.test(t, u);
}
@Override
public Function<Exception, RuntimeException> exceptionMapper() {
return exceptionMapper;
}
}.uncheck();
}
/**
* Converts a {@code BiPredicateWithException} to a lifted {@code BiPredicate}
* returning {@code false} in case of exception.
*
* @param predicate
* to be lifted
* @param <T>
* the type of the first argument to the predicate
* @param <U>
* the type of the second argument the predicate
* @param <E>
* the type of the potential exception
* @return the lifted predicate
* @see #lift()
* @throws NullPointerException
* if predicate is null
*/
static <T, U, E extends Exception> BiPredicate<T, U> lifted(BiPredicateWithException<T, U, E> predicate) {
return verifyPredicate(predicate).lift();
}
/**
* Converts a {@code BiPredicateWithException} to a lifted {@code BiPredicate}
* returning {@code false} in case of exception.
*
* @param predicate
* to be lifted
* @param <T>
* the type of the first argument to the predicate
* @param <U>
* the type of the second argument the predicate
* @param <E>
* the type of the potential exception
* @return the lifted predicate
* @see #ignore()
* @throws NullPointerException
* if predicate is null
*/
static <T, U, E extends Exception> BiPredicate<T, U> ignored(BiPredicateWithException<T, U, E> predicate) {
return verifyPredicate(predicate).ignore();
}
/**
* Converts a {@code BiPredicateWithException} to a lifted {@code BiPredicate}
* returning a default value in case of exception.
*
* @param predicate
* to be lifted
* @param defaultValue
* value in case of exception
* @param <T>
* the type of the first argument to the predicate
* @param <U>
* the type of the second argument the predicate
* @param <E>
* the type of the potential exception
* @return the lifted predicate
* @see #ignore()
* @see #ignored(BiPredicateWithException)
* @throws NullPointerException
* if predicate is null
* @since 3.0.0
*/
static <T, U, E extends Exception> BiPredicate<T, U> ignored(BiPredicateWithException<T, U, E> predicate,
boolean defaultValue) {
verifyPredicate(predicate);
return new BiPredicateWithException<T, U, E>() {
@Override
public boolean test(T t, U u) throws E {
return predicate.test(t, u);
}
@Override
public boolean defaultValue() {
return defaultValue;
}
}.ignore();
}
}