    001// Copyright 2011 The Apache Software Foundation
    002//
    003// Licensed under the Apache License, Version 2.0 (the "License");
    004// you may not use this file except in compliance with the License.
    005// You may obtain a copy of the License at
    006//
    007// http://www.apache.org/licenses/LICENSE-2.0
    008//
    009// Unless required by applicable law or agreed to in writing, software
    010// distributed under the License is distributed on an "AS IS" BASIS,
    011// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    012// See the License for the specific language governing permissions and
    013// limitations under the License.
    014
    015package org.apache.tapestry5.plastic;
    016
    017/**
    018 * The result of a {@linkplain MethodHandle#invoke(Object, Object...) method invocation}, which
    019 * encapsulates the actual return value (if any), as well as any checked exception.
    020 */
    021public interface MethodInvocationResult
    022{
    023    /**
    024     * Returns the actual value returned from the method invocation, if any. This will be null
    025     * if the invocation threw a checked exception, or the method itself is void.
    026     */
    027    Object getReturnValue();
    028
    029    /**
    030     * If the invocation threw a checked exception, then this method throws that exception wrapped
    031     * as the cause of a new RuntimeException. Otherwise, this method does nothing.
    032     */
    033    void rethrow();
    034
    035    /** Returns true if the method invocation threw a checked exception. */
    036    boolean didThrowCheckedException();
    037
    038    /**
    039     * Retrieves the checked exception assignable to the indicated type, or null if
    040     * the invocation did not throw a checked exception or the thrown exception is not
    041     * assignable.
    042     */
    043    <T extends Throwable> T getCheckedException(Class<T> exceptionType);
    044}