net.form105.rm.base.Container.java Source code

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Here is the source code for net.form105.rm.base.Container.java

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/*
 * XMLContainer.java, Oct 21, 2007, 9:21:12 PM
 *
 * Copyright (c) 2007, form105 Heiko Kundlacz
 * Licensed under the GNU GPL Version 3. For full terms see the file license.txt
 */
package net.form105.rm.base;

import java.io.File;
import java.util.List;

import net.form105.rm.base.util.xml.XMLLoader;

import org.apache.log4j.Logger;
import org.apache.log4j.PropertyConfigurator;
import org.dom4j.Document;
import org.dom4j.Element;
import org.picocontainer.DefaultPicoContainer;
import org.picocontainer.MutablePicoContainer;
import org.picocontainer.PicoContainer;
import org.picocontainer.behaviors.Caching;

/**
 * The PicoContainer used for starting basic services. The individual classes
 * will be loaded from an xml file in the config folder. Each class that should
 * be instantiated must be included in the container.xml file. The PicoContainer
 * is a IoC Container which resolves its dependencies automatically and
 * instantiates each required class to fullfill the instantiation parameters.
 * The factoryContainer is a container to fetch instances by a class name.
 * 
 * @author heiko
 */
public class Container {

    private Logger logger = Logger.getLogger(Container.class);
    private static Container instance;
    private static MutablePicoContainer container;
    private static MutablePicoContainer factoryContainer;
    //private static MutablePicoContainer mContainer;

    private ContainerConfiguration configuration;

    static {

        instance = new Container();
        instance.initialize();

    }

    public void initialize() {
        container = new DefaultPicoContainer(new Caching());
        factoryContainer = container.addChildContainer(new DefaultPicoContainer(container));

    }

    /**
     * Static method to get a pico container singleton
     * 
     * @return
     */
    public static PicoContainer getContainer() {
        return container;
    }

    /**
     * Static method to get a pico container singleton which returns an instance
     * of a class
     * 
     * @return
     */
    public static PicoContainer getFactoryContainer() {
        return factoryContainer;
    }

    public static Object getByObjectId(String id) {
        if (getContainer().getComponent(id) != null) {
            return getContainer().getComponent(id);
        }
        return getFactoryContainer().getComponent(id);
    }

    @SuppressWarnings(value = { "unchecked", "rawtypes" })
    public static Object getByClass(Class clazz) {
        if (getContainer().getComponent(clazz) != null) {
            return getContainer().getComponent(clazz);
        }
        return getFactoryContainer().getComponent(clazz);
    }

    public static Container getInstance() {
        return instance;
    }

    /**
     * Building the pico container based on the nano container. To create a pico
     * container a configuration must be available
     * 
     * @param builder
     * @param parentContainer
     * @param scope
     * @return
     */
    public void load(ContainerConfiguration configuration) {

        if (container.getComponents().size() > 0 || factoryContainer.getComponents().size() > 0) {
            System.err.println("Can't do Container.load(): Container already started. Do nothing!");
            return;
        }
        this.configuration = configuration;

        // check for log4j config file

        // 1st of all - load log4j
        String configDir = configuration.getConfigurationDirectory();
        String log4jConfigPath = configDir + "log4j.properties";
        File file = new File(log4jConfigPath);
        if (!file.exists()) {
            System.err.println("Error: Log4j configuration file doesn't exit: " + log4jConfigPath);
        }
        PropertyConfigurator.configureAndWatch(configDir + File.separator + "log4j.properties");
        logger = Logger.getLogger(Container.class);

        XMLLoader loader = new XMLLoader(configuration.getPath());
        Document document = loader.parseFile();
        Element rootElement = document.getRootElement();
        List<Element> classElements = rootElement.elements();

        for (Element element : classElements) {

            try {
                if (element.attribute("factory") == null) {
                    String className = element.attributeValue("class");
                    String id = element.attributeValue("id");
                    logger.info("Loading class for container: " + className);
                    Class containerClass = Class.forName(className);
                    container.addComponent(id, containerClass);
                } else {
                    String className = element.attributeValue("class");
                    String key = element.attributeValue("id");
                    logger.info("Loading class for factory container: " + className);
                    Class containerClass = Class.forName(className);
                    factoryContainer.addComponent(key, containerClass);
                }

            } catch (ClassNotFoundException ex) {
                logger.error(ex, ex);
            }
        }

        //container.addChildContainer(factoryContainer);
        //factoryContainer.addChildContainer(container);
        factoryContainer.start();

    }

    public void stopAll() {
        container.stop();
    }

    /**
     * Get the configuration for this container
     * 
     * @return
     */
    public ContainerConfiguration getConfiguration() {
        return configuration;
    }

    public void unload() {
        container.stop();
        factoryContainer.stop();
    }

    public void getPersistanceContainer() {

    }

}