    001// Copyright 2008, 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.internal.spring;
    016
    017import org.apache.tapestry5.ioc.internal.util.InternalUtils;
    018import org.apache.tapestry5.spring.ApplicationContextCustomizer;
    019import org.apache.tapestry5.spring.TapestryApplicationContext;
    020import org.springframework.context.ApplicationContextException;
    021import org.springframework.web.context.ConfigurableWebApplicationContext;
    022import org.springframework.web.context.ContextLoader;
    023
    024import javax.servlet.ServletContext;
    025
    026public class CustomizingContextLoader extends ContextLoader
    027{
    028    private final ApplicationContextCustomizer customizer;
    029
    030    public CustomizingContextLoader(ApplicationContextCustomizer customizer)
    031    {
    032        this.customizer = customizer;
    033    }
    034
    035    @Override
    036    protected void customizeContext(ServletContext servletContext, ConfigurableWebApplicationContext applicationContext)
    037    {
    038        customizer.customizeApplicationContext(servletContext, applicationContext);
    039    }
    040
    041    @Override
    042    protected Class determineContextClass(ServletContext servletContext) throws ApplicationContextException
    043    {
    044        String contextClassName = servletContext.getInitParameter(CONTEXT_CLASS_PARAM);
    045
    046        if (InternalUtils.isNonBlank(contextClassName))
    047        {
    048            Class result = super.determineContextClass(servletContext);
    049
    050            if (!TapestryApplicationContext.class.isAssignableFrom(result))
    051                throw new IllegalArgumentException(String.format(
    052                        "When using the Tapestry/Spring integration library, you must specifiy a context class that extends from %s. Class %s does not. Update the '%s' servlet context init parameter.",
    053                        TapestryApplicationContext.class.getName(),
    054                        result.getName(),
    055                        CONTEXT_CLASS_PARAM));
    056
    057            return result;
    058        }
    059
    060        return TapestryApplicationContext.class;
    061    }
    062}