pluginmanager.java

openfire 服务器源码下载

        // plugin are still in memory.
        File dir = new File(pluginDirectory, pluginName);
        // Give the plugin 2 seconds to unload.
        try {
            Thread.sleep(2000);
            // Ask the system to clean up references.
            System.gc();
            int count = 0;
            while (!deleteDir(dir) && count < 5) {
                Log.warn("Error unloading plugin " + pluginName + ". " + "Will attempt again momentarily.");
                Thread.sleep(8000);
                count++;
                // Ask the system to clean up references.
                System.gc();
            }
        } catch (InterruptedException e) {
            Log.error(e);
        }

        if (plugin != null && !dir.exists()) {
            // Unregister plugin caches
            PluginCacheRegistry.getInstance().unregisterCaches(pluginName);

            // See if this is a child plugin. If it is, we should unload
            // the parent plugin as well.
            if (childPluginMap.containsKey(plugin)) {
                unloadPlugin(childPluginMap.get(plugin));
            }
            childPluginMap.remove(plugin);
            firePluginDestroyedEvent(pluginName, plugin);
        }
        else if (plugin != null) {
            // Restore references since we failed to remove the plugin
            plugins.put(pluginName, plugin);
            pluginDirs.put(plugin, pluginFile);
            classloaders.put(plugin, pluginLoader);
        }
    }

    private void firePluginDestroyedEvent(String name, Plugin plugin) {
        for (PluginListener listener : pluginListeners) {
            listener.pluginDestroyed(name, plugin);
        }
    }

    /**
     * Loads a class from the classloader of a plugin.
     *
     * @param plugin the plugin.
     * @param className the name of the class to load.
     * @return the class.
     * @throws ClassNotFoundException if the class was not found.
     * @throws IllegalAccessException if not allowed to access the class.
     * @throws InstantiationException if the class could not be created.
     */
    public Class loadClass(Plugin plugin, String className) throws ClassNotFoundException,
        IllegalAccessException, InstantiationException {
        PluginClassLoader loader = classloaders.get(plugin);
        return loader.loadClass(className);
    }

    /**
     * Returns a plugin's dev environment if development mode is enabled for
     * the plugin.
     *
     * @param plugin the plugin.
     * @return the plugin dev environment, or <tt>null</tt> if development
     *         mode is not enabled for the plugin.
     */
    public PluginDevEnvironment getDevEnvironment(Plugin plugin) {
        return pluginDevelopment.get(plugin);
    }

    /**
     * Returns the name of a plugin. The value is retrieved from the plugin.xml file
     * of the plugin. If the value could not be found, <tt>null</tt> will be returned.
     * Note that this value is distinct from the name of the plugin directory.
     *
     * @param plugin the plugin.
     * @return the plugin's name.
     */
    public String getName(Plugin plugin) {
        String name = getElementValue(plugin, "/plugin/name");
        String pluginName = pluginDirs.get(plugin).getName();
        if (name != null) {
            return AdminConsole.getAdminText(name, pluginName);
        }
        else {
            return pluginName;
        }
    }

    /**
     * Returns the description of a plugin. The value is retrieved from the plugin.xml file
     * of the plugin. If the value could not be found, <tt>null</tt> will be returned.
     *
     * @param plugin the plugin.
     * @return the plugin's description.
     */
    public String getDescription(Plugin plugin) {
        String pluginName = pluginDirs.get(plugin).getName();
        return AdminConsole.getAdminText(getElementValue(plugin, "/plugin/description"), pluginName);
    }

    /**
     * Returns the author of a plugin. The value is retrieved from the plugin.xml file
     * of the plugin. If the value could not be found, <tt>null</tt> will be returned.
     *
     * @param plugin the plugin.
     * @return the plugin's author.
     */
    public String getAuthor(Plugin plugin) {
        return getElementValue(plugin, "/plugin/author");
    }

    /**
     * Returns the version of a plugin. The value is retrieved from the plugin.xml file
     * of the plugin. If the value could not be found, <tt>null</tt> will be returned.
     *
     * @param plugin the plugin.
     * @return the plugin's version.
     */
    public String getVersion(Plugin plugin) {
        return getElementValue(plugin, "/plugin/version");
    }

     /**
     * Returns the minimum server version this plugin can run within. The value is retrieved from the plugin.xml file
     * of the plugin. If the value could not be found, <tt>null</tt> will be returned.
     *
     * @param plugin the plugin.
     * @return the plugin's version.
     */
    public String getMinServerVersion(Plugin plugin) {
        return getElementValue(plugin, "/plugin/minServerVersion");
    }

    /**
     * Returns the database schema key of a plugin, if it exists. The value is retrieved
     * from the plugin.xml file of the plugin. If the value could not be found, <tt>null</tt>
     * will be returned.
     *
     * @param plugin the plugin.
     * @return the plugin's database schema key or <tt>null</tt> if it doesn't exist.
     */
    public String getDatabaseKey(Plugin plugin) {
        return getElementValue(plugin, "/plugin/databaseKey");
    }

    /**
     * Returns the database schema version of a plugin, if it exists. The value is retrieved
     * from the plugin.xml file of the plugin. If the value could not be found, <tt>-1</tt>
     * will be returned.
     *
     * @param plugin the plugin.
     * @return the plugin's database schema version or <tt>-1</tt> if it doesn't exist.
     */
    public int getDatabaseVersion(Plugin plugin) {
        String versionString = getElementValue(plugin, "/plugin/databaseVersion");
        if (versionString != null) {
            try {
                return Integer.parseInt(versionString.trim());
            }
            catch (NumberFormatException nfe) {
                Log.error(nfe);
            }
        }
        return -1;
    }

    /**
     * Returns the license agreement type that the plugin is governed by. The value
     * is retrieved from the plugin.xml file of the plugin. If the value could not be
     * found, {@link License#other} is returned.
     *
     * @param plugin the plugin.
     * @return the plugin's license agreement.
     */
    public License getLicense(Plugin plugin) {
        String licenseString = getElementValue(plugin, "/plugin/licenseType");
        if (licenseString != null) {
            try {
                // Attempt to load the get the license type. We lower-case and
                // trim the license type to give plugin author's a break. If the
                // license type is not recognized, we'll log the error and default
                // to "other".
                return License.valueOf(licenseString.toLowerCase().trim());
            }
            catch (IllegalArgumentException iae) {
                Log.error(iae);
            }
        }
        return License.other;
    }

    /**
     * Returns the classloader of a plugin.
     *
     * @param plugin the plugin.
     * @return the classloader of the plugin.
     */
    public PluginClassLoader getPluginClassloader(Plugin plugin) {
        return classloaders.get(plugin);
    }

    /**
     * Returns the value of an element selected via an xpath expression from
     * a Plugin's plugin.xml file.
     *
     * @param plugin the plugin.
     * @param xpath  the xpath expression.
     * @return the value of the element selected by the xpath expression.
     */
    private String getElementValue(Plugin plugin, String xpath) {
        File pluginDir = pluginDirs.get(plugin);
        if (pluginDir == null) {
            return null;
        }
        try {
            File pluginConfig = new File(pluginDir, "plugin.xml");
            if (pluginConfig.exists()) {
                SAXReader saxReader = new SAXReader();
                saxReader.setEncoding("UTF-8");
                Document pluginXML = saxReader.read(pluginConfig);
                Element element = (Element)pluginXML.selectSingleNode(xpath);
                if (element != null) {
                    return element.getTextTrim();
                }
            }
        }
        catch (Exception e) {
            Log.error(e);
        }
        return null;
    }

    /**
     * An enumberation for plugin license agreement types.
     */
    @SuppressWarnings({"UnnecessarySemicolon"})  // Support for QDox Parser
    public enum License {

        /**
         * The plugin is distributed using a commercial license.
         */
        commercial,

        /**
         * The plugin is distributed using the GNU Public License (GPL).
         */
        gpl,

        /**
         * The plugin is distributed using the Apache license.
         */
        apache,

        /**
         * The plugin is for internal use at an organization only and is not re-distributed.
         */
        internal,

        /**
         * The plugin is distributed under another license agreement not covered by
         * one of the other choices. The license agreement should be detailed in the
         * plugin Readme.
         */
        other;
    }

    /**
     * A service that monitors the plugin directory for plugins. It periodically
     * checks for new plugin JAR files and extracts them if they haven't already
     * been extracted. Then, any new plugin directories are loaded.
     */
    private class PluginMonitor implements Runnable {

        /**
         * Tracks if the monitor is currently running.
         */
        private boolean running = false;

        /**
         * True if the monitor has been executed at least once. After the first iteration in {@link #run}
         * this variable will always be true.
         * */
        private boolean executed = false;

        /**
         * True when it's the first time the plugin monitor process runs. This is helpful for
         * bootstrapping purposes.
         */
        private boolean firstRun = true;

        public void run() {
            // If the task is already running, return.
            synchronized (this) {
                if (running) {
                    return;
                }