001// Copyright 2009 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.ioc.internal.util;
016
017import java.lang.reflect.Type;
018
019/**
020 * Used when invoking a contribute method to guard against a request for the wrong type of configuration interface.
021 */
022public class WrongConfigurationTypeGuard implements InjectionResources
023{
024    private final String serviceId;
025
026    private final Class guardType;
027
028    private final Class expectedType;
029
030    public WrongConfigurationTypeGuard(String serviceId, Class guardType, Class expectedType)
031    {
032        this.serviceId = serviceId;
033        this.guardType = guardType;
034        this.expectedType = expectedType;
035    }
036
037    @Override
038    public <T> T findResource(Class<T> type, Type genericType)
039    {
040        if (type == guardType)
041            throw new IllegalArgumentException(String.format("Service '%s' is configured using %s, not %s.",
042                                                             serviceId,
043                                                             expectedType.getName(), guardType.getName()));
044
045        return null;
046    }
047}