http/base/src/main/java/org/apache/felix/http/base/internal/service/ServletContextManager.java

/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.apache.felix.http.base.internal.service;

import java.util.Map;
import java.util.WeakHashMap;

import javax.servlet.ServletContext;

import org.apache.felix.http.base.internal.context.ExtServletContext;
import org.apache.felix.http.base.internal.registry.PerContextHandlerRegistry;
import org.osgi.framework.Bundle;
import org.osgi.service.http.HttpContext;

public final class ServletContextManager
{
    private final Bundle bundle;
    private final ServletContext context;
    private final Map<HttpContext, ExtServletContext> contextMap;
    private final boolean sharedAttributes;
    private final PerContextHandlerRegistry handlerRegistry;

    public ServletContextManager(
            final Bundle bundle,
            final ServletContext context,
            final boolean sharedAttributes,
            final PerContextHandlerRegistry registry)
    {
        this.bundle = bundle;
        this.context = context;
        // FELIX-4424 : avoid classloader leakage through HttpContext, for now this is sufficient,
        // the real fix should be to remove ExtServletContext's when the usage count of HttpContext
        // drops to zero.
        this.contextMap = new WeakHashMap<HttpContext, ExtServletContext>();
        this.sharedAttributes = sharedAttributes;
        this.handlerRegistry = registry;
    }

    public ExtServletContext getServletContext(HttpContext httpContext)
    {
        ExtServletContext context;
        synchronized (this.contextMap)
        {
            context = this.contextMap.get(httpContext);
            if (context == null)
            {
                context = addServletContext(httpContext);
            }
        }
        return context;
    }

    private ExtServletContext addServletContext(HttpContext httpContext)
    {
        ExtServletContext context = new ServletContextImpl(this.bundle,
                this.context,
                httpContext,
                this.sharedAttributes,
                handlerRegistry);
        this.contextMap.put(httpContext, context);
        return context;
    }
}