@FunctionalInterface publicinterfaceRunnable { /** * When an object implementing interface <code>Runnable</code> is used * to create a thread, starting the thread causes the object's * <code>run</code> method to be called in that separately executing * thread. * <p> * The general contract of the method <code>run</code> is that it may * take any action whatsoever. * * @see java.lang.Thread#run() */ publicabstractvoidrun(); }
/** * Performs this operation on the given argument. * * @param t the input argument */ voidaccept(T t);
/** * Returns a composed {@code Consumer} that performs, in sequence, this * operation followed by the {@code after} operation. If performing either * operation throws an exception, it is relayed to the caller of the * composed operation. If performing this operation throws an exception, * the {@code after} operation will not be performed. * * @param after the operation to perform after this operation * @return a composed {@code Consumer} that performs in sequence this * operation followed by the {@code after} operation * @throws NullPointerException if {@code after} is null */ default Consumer<T> andThen(Consumer<? super T> after) { Objects.requireNonNull(after); return (T t) -> { accept(t); after.accept(t); }; } }
/** * Applies this function to the given argument. * * @param t the function argument * @return the function result */ R apply(T t);
/** * Returns a composed function that first applies the {@code before} * function to its input, and then applies this function to the result. * If evaluation of either function throws an exception, it is relayed to * the caller of the composed function. * * @param <V> the type of input to the {@code before} function, and to the * composed function * @param before the function to apply before this function is applied * @return a composed function that first applies the {@code before} * function and then applies this function * @throws NullPointerException if before is null * * @see #andThen(Function) */ default <V> Function<V, R> compose(Function<? super V, ? extends T> before) { Objects.requireNonNull(before); return (V v) -> apply(before.apply(v)); }
/** * Returns a composed function that first applies this function to * its input, and then applies the {@code after} function to the result. * If evaluation of either function throws an exception, it is relayed to * the caller of the composed function. * * @param <V> the type of output of the {@code after} function, and of the * composed function * @param after the function to apply after this function is applied * @return a composed function that first applies this function and then * applies the {@code after} function * @throws NullPointerException if after is null * * @see #compose(Function) */ default <V> Function<T, V> andThen(Function<? super R, ? extends V> after) { Objects.requireNonNull(after); return (T t) -> after.apply(apply(t)); }
/** * Returns a function that always returns its input argument. * * @param <T> the type of the input and output objects to the function * @return a function that always returns its input argument */ static <T> Function<T, T> identity() { return t -> t; } }
/** * Applies this operator to the given operands. * * @param left the first operand * @param right the second operand * @return the operator result */ intapplyAsInt(int left, int right); }
@FunctionalInterface publicinterfaceBinaryOperator<T> extendsBiFunction<T,T,T> { /** * Returns a {@link BinaryOperator} which returns the lesser of two elements * according to the specified {@code Comparator}. * * @param <T> the type of the input arguments of the comparator * @param comparator a {@code Comparator} for comparing the two values * @return a {@code BinaryOperator} which returns the lesser of its operands, * according to the supplied {@code Comparator} * @throws NullPointerException if the argument is null */ publicstatic <T> BinaryOperator<T> minBy(Comparator<? super T> comparator) { Objects.requireNonNull(comparator); return (a, b) -> comparator.compare(a, b) <= 0 ? a : b; }
/** * Returns a {@link BinaryOperator} which returns the greater of two elements * according to the specified {@code Comparator}. * * @param <T> the type of the input arguments of the comparator * @param comparator a {@code Comparator} for comparing the two values * @return a {@code BinaryOperator} which returns the greater of its operands, * according to the supplied {@code Comparator} * @throws NullPointerException if the argument is null */ publicstatic <T> BinaryOperator<T> maxBy(Comparator<? super T> comparator) { Objects.requireNonNull(comparator); return (a, b) -> comparator.compare(a, b) >= 0 ? a : b; } }
/** * Evaluates this predicate on the given argument. * * @param t the input argument * @return {@code true} if the input argument matches the predicate, * otherwise {@code false} */ booleantest(T t);
/** * 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 */ default Predicate<T> and(Predicate<? super T> other) { Objects.requireNonNull(other); return (t) -> test(t) && other.test(t); }
/** * Returns a predicate that represents the logical negation of this * predicate. * * @return a predicate that represents the logical negation of this * predicate */ default Predicate<T> negate() { return (t) -> !test(t); }
/** * 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 */ default Predicate<T> or(Predicate<? super T> other) { Objects.requireNonNull(other); return (t) -> test(t) || other.test(t); }
/** * Returns a predicate that tests if two arguments are equal according * to {@link Objects#equals(Object, Object)}. * * @param <T> the type of arguments to the predicate * @param targetRef the object reference with which to compare for equality, * which may be {@code null} * @return a predicate that tests if two arguments are equal according * to {@link Objects#equals(Object, Object)} */ static <T> Predicate<T> isEqual(Object targetRef) { return (null == targetRef) ? Objects::isNull : object -> targetRef.equals(object); } }