    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.internal.plastic;
    016
    017    import org.apache.tapestry5.plastic.MethodHandle;
    018    import org.apache.tapestry5.plastic.MethodInvocationResult;
    019
    020    public class MethodHandleImpl implements MethodHandle
    021    {
    022        private final String className, methodDescription;
    023
    024        private final int methodIndex;
    025
    026        protected volatile PlasticClassHandleShim shim;
    027
    028        public MethodHandleImpl(String className, String methodDescription, int methodIndex)
    029        {
    030            this.className = className;
    031            this.methodDescription = methodDescription;
    032            this.methodIndex = methodIndex;
    033        }
    034
    035        public String toString()
    036        {
    037            return String.format("MethodHandle[%s %s]", className, methodDescription);
    038        }
    039
    040        public MethodInvocationResult invoke(Object instance, Object... arguments)
    041        {
    042
    043            if (instance == null)
    044                throw new NullPointerException(String.format(
    045                        "Unable to invoke method %s of class %s, as provided instance is null.", methodDescription,
    046                        className));
    047
    048            return shim.invoke(instance, methodIndex, arguments);
    049        }
    050
    051    }