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/*
 * Copyright 2016 Liam Williams .
 *
 * This file is part of business-flows.
 *
 * 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 io.github.theangrydev.businessflows;

/**
 * Attempt to perform an action that will either:
 * 
 *     Succeed and return a {@link Result}
 *     Result in a technical failure and throw any kind of {@link Exception}
 * 
 *
 * @param  The type of happy object that will be produced in the successful case
 */
@FunctionalInterface
public interface Attempt {

    /**
     * @return The happy object that the method attempts to produce
     * @throws Exception If there was a technical failure in producing
     */
    Result attempt() throws Exception;

    /**
     * Helper method to extend an existing {@link Attempt} by mapping the result in the successful case to a new type.
     *
     * @param after The {@link Mapping} to apply after {@link #attempt()} is called
     * @param  The new type of happy object that will be produced in the successful case
     * @return A {@link Attempt} that will apply this and then the given mapping
     */
    default  Attempt andThen(Mapping after) {
        return () -> after.map(attempt());
    }
}