    001// Copyright 2007, 2008, 2012 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.commons.internal.services;
    016
    017import java.util.Map;
    018
    019import org.apache.tapestry5.commons.services.DataTypeAnalyzer;
    020import org.apache.tapestry5.commons.services.PropertyAdapter;
    021import org.apache.tapestry5.commons.util.StrategyRegistry;
    022
    023/**
    024 * The default data type analyzer, which is based entirely on the type of the property (and not on annotations or naming
    025 * conventions). This is based on a configuration of property type class to string provided as an IoC service
    026 * configuration.
    027 */
    028public class DefaultDataTypeAnalyzer implements DataTypeAnalyzer, Runnable
    029{
    030    private final StrategyRegistry<String> registry;
    031
    032    public DefaultDataTypeAnalyzer(Map<Class, String> configuration)
    033    {
    034        registry = StrategyRegistry.newInstance(String.class, configuration);
    035    }
    036
    037    /**
    038     * Clears the registry on an invalidation event (this is because the registry caches results, and the keys are
    039     * classes that may be component classes from the invalidated component class loader).
    040     */
    041    public void run()
    042    {
    043        registry.clearCache();
    044    }
    045
    046    public String identifyDataType(PropertyAdapter adapter)
    047    {
    048        Class propertyType = adapter.getType();
    049
    050        String dataType = registry.get(propertyType);
    051
    052        // To avoid "no strategy" exceptions, we expect a contribution of Object.class to the empty
    053        // string. We convert that back to a null.
    054
    055        if (dataType.equals(""))
    056            return null;
    057
    058        return dataType;
    059    }
    060}