001// Copyright 2008, 2010, 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.services;
016
017import org.apache.tapestry5.internal.plastic.PlasticInternalUtils;
018import org.apache.tapestry5.ioc.annotations.PostInjection;
019import org.apache.tapestry5.ioc.internal.util.CollectionFactory;
020import org.apache.tapestry5.ioc.services.PlasticProxyFactory;
021import org.apache.tapestry5.ioc.services.TypeCoercer;
022import org.apache.tapestry5.services.ComponentClasses;
023import org.apache.tapestry5.services.ComponentLayer;
024import org.apache.tapestry5.services.InvalidationEventHub;
025import org.apache.tapestry5.services.InvalidationListener;
026
027import java.util.Map;
028
029public class ComponentClassCacheImpl implements ComponentClassCache
030{
031    private final Map<String, Class> cache = CollectionFactory.newConcurrentMap();
032
033    private final PlasticProxyFactory plasticFactory;
034
035    private final TypeCoercer typeCoercer;
036
037    public ComponentClassCacheImpl(@ComponentLayer
038    PlasticProxyFactory plasticFactory, TypeCoercer typeCoercer)
039    {
040        this.plasticFactory = plasticFactory;
041        this.typeCoercer = typeCoercer;
042    }
043
044    @PostInjection
045    public void setupInvalidation(@ComponentClasses InvalidationEventHub hub) {
046        hub.clearOnInvalidation(cache);
047    }
048
049    @SuppressWarnings("unchecked")
050    public Object defaultValueForType(String className)
051    {
052        Class clazz = forName(className);
053
054        if (!clazz.isPrimitive())
055            return null;
056
057        // Remembering that 0 coerces to boolean false, this covers all the primitive
058        // types (boolean, int, short, etc.)
059        return typeCoercer.coerce(0, clazz);
060    }
061
062    public Class forName(String className)
063    {
064        Class result = cache.get(className);
065
066        if (result == null)
067        {
068            result = lookupClassForType(className);
069
070            cache.put(className, result);
071        }
072
073        return result;
074    }
075
076    private Class lookupClassForType(String className)
077    {
078        ClassLoader componentLoader = plasticFactory.getClassLoader();
079        try
080        {
081            return PlasticInternalUtils.toClass(componentLoader, className);
082        }
083        catch (ClassNotFoundException ex)
084        {
085            throw new RuntimeException(ex);
086        }
087    }
088}