001    // Copyright 2004, 2005 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.hivemind.service;
016    
017    /**
018     * Represents a created method on a class; used to add catch handlers.
019     * 
020     * @see org.apache.hivemind.service.ClassFab#addMethod(int, MethodSignature, String)
021     */
022    public interface MethodFab
023    {
024        /**
025         * Adds a catch to the method. The body must end with a return or throw. The special Javassist
026         * varaiable <code>$e</code> represents the caught exception.
027         */
028        public void addCatch(Class exceptionClass, String catchBody);
029    
030        /**
031         * Extends the existing method with additional code. The new body can reference the return value
032         * generated by the existing body using the special variable <code>$_</code>, for example
033         * <code>$_ = 2 * $_</code>.
034         * 
035         * @param body
036         *            a block to execute after any existing code in the method
037         * @param asFinally
038         *            if true, the block provided wil execute as with a finally block (even if an
039         *            exception is thrown)
040         */
041    
042        public void extend(String body, boolean asFinally);
043    }