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    
015    package 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     */
021    public 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    }