com.easyjf.container.impl.SingletonContainerLoader.java Source code

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Here is the source code for com.easyjf.container.impl.SingletonContainerLoader.java

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/*
 * Copyright 2006-2008 the original author or authors.
 * 
 * Licensed 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 com.easyjf.container.impl;

import java.util.HashMap;
import java.util.Map;

import org.dom4j.Document;
import org.dom4j.DocumentException;
import org.dom4j.io.SAXReader;

import com.easyjf.container.Container;
import com.easyjf.web.config.BeanConfigReader;

/**
 * Create {@link Container} instance from singleton .
 * 
 * @author ecsoftcn@hotmail.com
 * 
 * @version $Id: SingletonContainerLoader.java, 2007-4-15 ?06:09:36 Tony Exp $
 */
public class SingletonContainerLoader {

    /** Container instances singleton */
    private static Map<String, Container> containers = new HashMap<String, Container>();

    /**
     * Obtain an instance of {@link Container} through the special configFile .
     * 
     * <p>
     * If the container is not initialized , then initial it .
     * 
     * @param configFile
     *            bean's configuration file
     * 
     * @return an instance of {@link Container}
     */
    public static Container getInstance(String configFile) {

        Container container = null;

        synchronized (SingletonContainerLoader.class) {

            container = containers.get(configFile);
            if (container == null) {
                // TODO ???

                // ?EasyJWeb?Loader?Loader?

                // DefaultContainer container =
                // ContainerLoader.getInstance(configFile);
                Document doc = null;
                try {
                    doc = new SAXReader().read(SingletonContainerLoader.class.getResourceAsStream(configFile));
                } catch (DocumentException e) {
                    throw new IllegalArgumentException(configFile + "is not a valid config file !");
                }

                // ?DefaultContainer??Container
                DefaultContainer defaultContainer = new DefaultContainer();
                defaultContainer.registerBeanDefinitions(BeanConfigReader.parseBeansFromDocument(doc));
                defaultContainer.refresh();

                container = defaultContainer;

                containers.put(configFile, container);
            }
        }

        return container;

    }

}