Spark研究笔记8：重要的工厂类PluginManager（原创） CVT

PluginManager 负责装载所有的插件和Workspaces。

私有域：

private final List<Plugin> plugins = new ArrayList<Plugin>();//Plugin接口

//PublicPlugin是注册的插件，字面含义是公开
    private final List<PublicPlugin> publicPlugins = new CopyOnWriteArrayList<PublicPlugin>();
//单例管理器
    private static PluginManager singleton;
    private static final Object LOCK = new Object();

//Plugins 目录下的文件
    public static File PLUGINS_DIRECTORY = new File(Spark.getBinDirectory().getParent(), "plugins").getAbsoluteFile();

    private Plugin pluginClass;
    private PluginClassLoader classLoader;

//黑名单插件，也就是被禁用的插件
    private Collection<String> _blacklistPlugins;

构造函数： 

private PluginManager() {
        try {
//定义PLUGINS_DIRECTORY
            PLUGINS_DIRECTORY = new File(Spark.getBinDirectory().getParentFile(), "plugins").getCanonicalFile();
        }
        catch (IOException e) {
            Log.error(e);
        }

        // Do not use deployable plugins if not installed.
        if (System.getProperty("plugin") == null) {
            movePlugins();
        }


        // Create the extension directory if one does not exist.
        if (!PLUGINS_DIRECTORY.exists()) {
            PLUGINS_DIRECTORY.mkdirs();
        }
        
        _blacklistPlugins = Default.getPluginBlacklist();

//Default.getPluginBlacklist定义了插件黑名单，在default.properties里设置，用于禁用插件，第132行：
# Put plugins here that you dont want enabled
# comma separated, case insensitive
# names of plugins can be found in the plugin.xml
# example: Fastpath,Jingle Client,Phone Client,Window Flashing Plugin
# default is empty
PLUGIN_BLACKLIST =
# Disable Plugins by entrypoint Class 
# Comma seperated, case sensitive
# example org.jivesoftware.fastpath.FastpathPlugin
# default is empty
PLUGIN_BLACKLIST_CLASS =
    }

几个重要的方法

　　/**
     * 载入所有的插件（通过plugins.xml、lib）
     */
    public void loadPlugins() {


　　/**
     载入已注册插件*/
    private Plugin loadPublicPlugin(File pluginDir) {


    /**
     * 插件初始化*/
    public void initializePlugins() {


    /**
     * 安装新插件*/
    public void addPlugin(PublicPlugin plugin) throws Exception {