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}