commandlistservmanager.java

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            Properties props = getStandardProperties();
            String listName = props.getProperty("LIST_NAME");

            XMLResources[] xmlResources = new XMLResources[names.length];
            for (int index = 0; index < names.length; index++) {
                xmlResources[index] = new XMLResources();
                xmlResources[index].init(xmlFile, names[index], listName, props);
            }
            return xmlResources;
        } catch (Exception e) {
            log(e.getMessage(), e);
            throw new ConfigurationException("Can't initialize:", e);
        }
    }

    public void init() throws MessagingException {

        try {
            //Well, i want a more complex configuration structure
            //of my mailet, so i have to cheat... and cheat i will...
            Configuration configuration = (Configuration) getField(getMailetConfig(), "configuration");

            //get name
            listName = configuration.getChild("listName").getValue();
            displayName = configuration.getChild("displayName").getValue();
            listOwner = configuration.getChild("listOwner").getValue();
            listDomain = configuration.getChild("listDomain").getValue();

            //initialize resources
            initializeResources();

            //get users store
            initUsersRepository();

            //get command packages
            loadCommandPackages(configuration);

            //load commands
            loadCommands(configuration);

            //register w/context
            getMailetContext().setAttribute(ICommandListservManager.ID + listName, this);
        } catch (Exception e) {
            throw new MessagingException(e.getMessage(), e);
        }
    }

    /**
     * Based on the to address get a valid or command or null
     * @param mailAddress
     * @return IListServCommand or null
     */
    public IListServCommand getCommandTarget(MailAddress mailAddress) {
        String commandName = getCommandName(mailAddress);
        return getCommand(commandName);
    }

    /**
     * <p>Called by the mailet container to allow the mailet to process a
     * message.</p>
     *
     * <p>This method is declared abstract so subclasses must override it.</p>
     *
     * @param mail - the Mail object that contains the MimeMessage and
     *          routing information
     * @throws MessagingException - if an exception occurs that interferes with the mailet's normal operation
     *          occurred
     */
    public void service(Mail mail) throws MessagingException {
        if (mail.getRecipients().size() != 1) {
            getMailetContext().bounce(mail, "You can only send one command at a time to this listserv manager.");
            return;
        }
        MailAddress mailAddress = (MailAddress) mail.getRecipients().iterator().next();
        IListServCommand command = getCommandTarget(mailAddress);

        if (command == null) {
            //don't recognize the command
            onError(mail,
                    "unkown command",
                    xmlResources.getString("command.not.understood", getStandardProperties()));
        }
        command.onCommand(mail);

        mail.setState(Mail.GHOST);
    }

    /**
     * Get the name of the command
     * @param mailAddress
     * @return the name of the command
     */
    protected String getCommandName(MailAddress mailAddress) {
        String user = mailAddress.getUser();
        int index = user.indexOf('-');
        String commandName = user.substring(++index);
        return commandName;
    }

    /**
     * initialize the resources
     * @throws Exception
     */
    protected void initializeResources() throws Exception {
        xmlResources = initXMLResources(new String[]{"List Manager"})[0];
    }

    /**
     * Fetch the repository of users
     */
    protected void initUsersRepository() {
        ComponentManager compMgr = (ComponentManager) getMailetContext().getAttribute(Constants.AVALON_COMPONENT_MANAGER);
        try {
            UsersStore usersStore = (UsersStore) compMgr.lookup("org.apache.james.services.UsersStore");
            String repName = getInitParameter("repositoryName");

            usersRepository = usersStore.getRepository(repName);
        } catch (Exception e) {
            log("Failed to retrieve Store component:" + e.getMessage());
        }
    }

    /**
     * Load an initialize all of the available commands
     * @param configuration
     * @throws ConfigurationException
     */
    protected void loadCommands(Configuration configuration) throws Exception {
        final Configuration commandConfigurations = configuration.getChild("commands");
        final Configuration[] commandConfs = commandConfigurations.getChildren("command");
        for (int index = 0; index < commandConfs.length; index++) {
            Configuration commandConf = commandConfs[index];
            String commandName = commandConf.getAttribute("name").toLowerCase();
            String className = commandConf.getAttribute("class");
            loadCommand(commandName, className, commandConf);
        }
    }

    /**
     * Loads and initializes a single command
     *
     * @param commandName
     * @param className
     * @param configuration
     * @throws ConfigurationException
     */
    protected void loadCommand(String commandName,
                               String className,
                               Configuration configuration)
            throws ConfigurationException, ClassNotFoundException, IllegalAccessException, InstantiationException {
        ClassLoader theClassLoader = getClass().getClassLoader();
        for (Iterator it = commandPackages.iterator(); it.hasNext();) {
            String packageName = (String) it.next();

            IListServCommand listServCommand = null;
            try {
                listServCommand = (IListServCommand) theClassLoader.loadClass(packageName + className).newInstance();
            } catch (Exception e) {
                //ignore
                continue;
            }
            listServCommand.init(this, configuration);
            commandMap.put(commandName, listServCommand);
            return;
        }

        throw new ConfigurationException("Unable to load listservcommand: " + commandName);
    }

    /**
     * loads all of the packages for the commands
     *
     * @param configuration
     * @throws ConfigurationException
     */
    protected void loadCommandPackages(Configuration configuration) throws ConfigurationException {
        commandPackages.add("");
        final Configuration packageConfiguration = configuration.getChild("commandpackages");
        final Configuration[] pkgConfs = packageConfiguration.getChildren("commandpackage");
        for (int index = 0; index < pkgConfs.length; index++) {
            Configuration conf = pkgConfs[index];
            String packageName = conf.getValue().trim();
            if (!packageName.endsWith(".")) {
                packageName += ".";
            }
            commandPackages.add(packageName);
        }
    }

    /**
     * Retrieves a data field, potentially defined by a super class.
     * @return null if not found, the object otherwise
     */
    protected static Object getField(Object instance, String name) throws IllegalAccessException {
        Class clazz = instance.getClass();
        Field[] fields;
        while (clazz != null) {
            fields = clazz.getDeclaredFields();
            for (int index = 0; index < fields.length; index++) {
                Field field = fields[index];
                if (field.getName().equals(name)) {
                    field.setAccessible(true);
                    return field.get(instance);
                }
            }
            clazz = clazz.getSuperclass();
        }

        return null;
    }
}