001/*
002 * (C) Copyright 2019 Nuxeo (http://nuxeo.com/) and others.
003 *
004 * Licensed under the Apache License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 *
008 *     http://www.apache.org/licenses/LICENSE-2.0
009 *
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 * See the License for the specific language governing permissions and
014 * limitations under the License.
015 *
016 * Contributors:
017 *     Kevin Leturc <kleturc@nuxeo.com>
018 */
019package org.nuxeo.common.function;
020
021import java.util.function.Supplier;
022
023/**
024 * @param <T> the type of results supplied by this supplier
025 * @param <E> the type of exception to throw
026 * @since 11.1
027 */
028@FunctionalInterface
029public interface ThrowableSupplier<T, E extends Throwable> {
030
031    T get() throws E;
032
033    /**
034     * @return this {@link ThrowableSupplier} as a {@link Supplier} throwing the checked exception as an unchecked one
035     */
036    default Supplier<T> toSupplier() {
037        return asSupplier(this);
038    }
039
040    /**
041     * @return the given {@link ThrowableSupplier} as a {@link Supplier} throwing the checked exception as an unchecked
042     *         one
043     */
044    static <T, E extends Throwable> Supplier<T> asSupplier(ThrowableSupplier<T, E> throwableSupplier) {
045        return () -> {
046            try {
047                return throwableSupplier.get();
048            } catch (Throwable t) { // NOSONAR
049                return FunctionUtils.sneakyThrow(t); // will never return
050            }
051        };
052    }
053
054}