    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.internal.plastic;
    016
    017import org.apache.tapestry5.plastic.MethodHandle;
    018import org.apache.tapestry5.plastic.MethodInvocationResult;
    019
    020public 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    @Override
    036    public String toString()
    037    {
    038        return String.format("MethodHandle[%s %s]", className, methodDescription);
    039    }
    040
    041    @Override
    042    public MethodInvocationResult invoke(Object instance, Object... arguments)
    043    {
    044
    045        if (instance == null)
    046            throw new NullPointerException(String.format(
    047                    "Unable to invoke method %s of class %s, as provided instance is null.", methodDescription,
    048                    className));
    049
    050        return shim.invoke(instance, methodIndex, arguments);
    051    }
    052
    053}