containerutil.java

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                foundConfig = true;

                try
                {
                    Configurator configurator = (Configurator) LocalUtil.classNewInstance(INIT_CUSTOM_CONFIGURATOR, value, Configurator.class);
                    configurator.configure(container);
                    log.debug("Loaded config from: " + value);
                }
                catch (Exception ex)
                {
                    log.warn("Failed to start custom configurator", ex);
                }
            }
        }

        return foundConfig;
    }

    /**
     * Annotations must not break 1.3, so we use reflection to create an
     * <code>org.directwebremoting.annotations.AnnotationsConfigurator</code>
     * and the catch all sorts of random exceptions for the benefit of
     * Websphere.
     * @param container The container to configure
     * @return true if the configuration worked.
     */
    public static boolean configureFromAnnotations(Container container)
    {
        try
        {
            Class annotationCfgClass = LocalUtil.classForName("org.directwebremoting.annotations.AnnotationsConfigurator");

            Configurator configurator = (Configurator) annotationCfgClass.newInstance();
            configurator.configure(container);

            log.debug("Java5 AnnotationsConfigurator enabled");
            return true;
        }
        catch (UnsupportedClassVersionError ex)
        {
            // This will happen in JDK 1.4 and below
            return false;
        }
        catch (ClassNotFoundException ex)
        {
            // This will happen when run in an IDE without the java5 tree
            log.warn("AnnotationsConfigurator is missing. Are you running from within an IDE?");
            return false;
        }
        catch (Exception ex)
        {
            // This happens if there is a bug in AnnotationsConfigurator
            log.warn("Failed to start annotations", ex);
            return false;
        }
        catch (Throwable ex)
        {
            if (ex.getClass().getName().equals(UnsupportedClassVersionError.class.getName()))
            {
                log.error("Caught impossible Throwable", ex);
                return false;
            }
            else if (ex.getClass().getName().equals(LinkageError.class.getName()))
            {
                log.error("Caught impossible Throwable", ex);
                return false;
            }
            else if (ex instanceof Error)
            {
                log.fatal("Rethrowing Error:" + ex);
                throw (Error) ex;
            }
            else
            {
                // This can't happen: We've handled all Exceptions, and
                // Errors, so we can't get to execute this code.
                log.error("Ilogical catch state", ex);
                return false;
            }
        }
    }

    /**
     * Allow all the configurators to have a go at the container in turn
     * @param container The container to configure
     * @param configurators A list of configurators to run against the container
     */
    public static void configure(Container container, List configurators)
    {
        // Allow all the configurators to have a go
        for (Iterator it = configurators.iterator(); it.hasNext();)
        {
            Configurator configurator = (Configurator) it.next();

            log.debug("** Adding config from " + configurator);
            configurator.configure(container);
        }
    }

    /**
     * Run all the default configuration options on a Container
     * @param container The container to configure
     * @param servletConfig The source of init parameters
     * @throws SAXException If the config file parse fails
     * @throws ParserConfigurationException If the config file parse fails
     * @throws IOException If the config file read fails
     */
    public static void configureContainerFully(Container container, ServletConfig servletConfig) throws IOException, ParserConfigurationException, SAXException
    {
        configureFromSystemDwrXml(container);
        boolean foundConfig = configureFromInitParams(container, servletConfig);

        // The default dwr.xml file that sits by web.xml
        boolean skip = Boolean.valueOf(servletConfig.getInitParameter(INIT_SKIP_DEFAULT)).booleanValue();
        IOException delayedIOException = null;
        if (!foundConfig && !skip)
        {
            try
            {
                configureFromDefaultDwrXml(container);
            }
            catch (IOException ex)
            {
                // This is fatal unless we are on JDK5+ AND using annotations
                delayedIOException = ex;
            }
        }

        if (!configureFromAnnotations(container))
        {
            log.debug("Java5 AnnotationsConfigurator disabled");

            if (delayedIOException != null)
            {
                throw delayedIOException;
            }
        }
    }

    /**
     * If helps some situations if people can get at the container by looking
     * in the servlet context, under some name.
     * The name is specified in an initParameter.
     * @param container The container to publish
     * @param servletConfig Source of initParams to dictate publishing and contexts to publish to
     */
    public static void publishContainer(Container container, ServletConfig servletConfig)
    {
        ServletContext servletContext = servletConfig.getServletContext();

        String publishName = servletConfig.getInitParameter(INIT_PUBLISH_CONTAINER);
        if (publishName != null)
        {
            servletContext.setAttribute(publishName, container);
        }

        List containers = (List) servletContext.getAttribute(ATTRIBUTE_CONTAINER_LIST);
        if (containers == null)
        {
            containers = new ArrayList();
        }
        containers.add(container);
        servletContext.setAttribute(ATTRIBUTE_CONTAINER_LIST, containers);
    }

    /**
     * Get a list of all known Containers for the given {@link ServletContext}
     * @param servletContext The context in which {@link Container}s are stored.
     * @return a list of published {@link Container}s.
     */
    public static List getAllPublishedContainers(ServletContext servletContext)
    {
        List containers = (List) servletContext.getAttribute(ATTRIBUTE_CONTAINER_LIST);
        if (containers == null)
        {
            containers = new ArrayList();
        }

        return containers;
    }

    /**
     * Internal use only.
     * <p>If we detect that the server is being shutdown then we want to kill
     * any reverse ajax threads.
     * @param containers The list of containers to look for ServerLoadMonitors in
     * @param title What causes this (for debug purposes)
     */
    public static void shutdownServerLoadMonitorsInContainerList(List containers, String title)
    {
        if (containers == null || containers.size() == 0)
        {
            log.debug("No containers to shutdown for: " + title);
            return;
        }

        log.debug("Shutting down containers for: " + title);
        for (Iterator it = containers.iterator(); it.hasNext();)
        {
            Container container = (Container) it.next();
            ServerLoadMonitor monitor = (ServerLoadMonitor) container.getBean(ServerLoadMonitor.class.getName());
            monitor.shutdown();
        }
    }

    /**
     * Create a bunch of debug information about a container
     * @param container The container to print debug information about
     */
    public static void debugConfig(Container container)
    {
        if (log.isDebugEnabled())
        {
            // Container level debug
            log.debug("Container");
            log.debug("  Type: " + container.getClass().getName());
            Collection beanNames = container.getBeanNames();
            for (Iterator it = beanNames.iterator(); it.hasNext();)
            {
                String name = (String) it.next();
                Object object = container.getBean(name);

                if (object instanceof String)
                {
                    log.debug("  Param: " + name + " = " + object + " (" + object.getClass().getName() + ")");
                }
                else
                {
                    log.debug("  Bean: " + name + " = " + object + " (" + object.getClass().getName() + ")");
                }
            }

            // AccessControl debugging
            AccessControl accessControl = (AccessControl) container.getBean(AccessControl.class.getName());
            log.debug("AccessControl");
            log.debug("  Type: " + accessControl.getClass().getName());

            // AjaxFilterManager debugging
            AjaxFilterManager ajaxFilterManager = (AjaxFilterManager) container.getBean(AjaxFilterManager.class.getName());
            log.debug("AjaxFilterManager");
            log.debug("  Type: " + ajaxFilterManager.getClass().getName());

            // ConverterManager debugging
            ConverterManager converterManager = (ConverterManager) container.getBean(ConverterManager.class.getName());
            log.debug("ConverterManager");
            log.debug("  Type: " + converterManager.getClass().getName());

            // CreatorManager debugging
            CreatorManager creatorManager = (CreatorManager) container.getBean(CreatorManager.class.getName());
            log.debug("CreatorManager");
            log.debug("  Type: " + creatorManager.getClass().getName());
            Collection creatorNames = creatorManager.getCreatorNames();
            for (Iterator it = creatorNames.iterator(); it.hasNext();)
            {
                String creatorName = (String) it.next();
                Creator creator = creatorManager.getCreator(creatorName);
                log.debug("  Creator: " + creatorName + " = " + creator + " (" + creator.getClass().getName() + ")");
            }
        }
    }

    /**
     * Init parameter: Set a dwr.xml config file.
     * This is only a prefix since we might have more than 1 config file.
     */
    public static final String INIT_CONFIG = "config";

    /**
     * Init parameter: Skip reading the default config file if none are specified.
     */
    public static final String INIT_SKIP_DEFAULT = "skipDefaultConfig";

    /**
     * Init parameter: If we are doing Servlet.log logging, to what level?
     */
    public static final String INIT_LOGLEVEL = "logLevel";

    /**
     * Init parameter: Should we publish the {@link Container} to the servlet
     * context, and if so, under what name?
     */
    public static final String INIT_PUBLISH_CONTAINER = "publishContainerAs";

    /**
     * Init parameter: If you wish to use a custom configurator, place its
     * class name here
     */
    public static final String INIT_CUSTOM_CONFIGURATOR = "customConfigurator";

    /**
     * The name under which we publish all {@link Container}s.
     */
    public static final String ATTRIBUTE_CONTAINER_LIST = "org.directwebremoting.ContainerList";

    /**
     * The log stream
     */
    private static final Logger log = Logger.getLogger(ContainerUtil.class);
}