avalonmailstore.java

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    public synchronized Component select(Object hint) throws ComponentException {
        Configuration repConf = null;
        try {
            repConf = (Configuration) hint;
        } catch (ClassCastException cce) {
            throw new ComponentException(
                "hint is of the wrong type. Must be a Configuration", cce);
        }
        String destination = null;
        String protocol = null;
        try {
            destination = repConf.getAttribute("destinationURL");
            int idx = destination.indexOf(':');
            if ( idx == -1 )
                throw new ComponentException(
                    "destination is malformed. Must be a valid URL: "
                    + destination);
            protocol = destination.substring(0,idx);
        } catch (ConfigurationException ce) {
            throw new ComponentException(
                "Malformed configuration has no destinationURL attribute", ce);
        }

        try
        {
            String type = repConf.getAttribute("type");
            String repID = destination + type;
            MailRepository reply = (MailRepository) repositories.get(repID);
            StringBuffer logBuffer = null;
            if (reply != null) {
                if (getLogger().isDebugEnabled()) {
                    logBuffer =
                        new StringBuffer(128)
                                .append("obtained repository: ")
                                .append(repID)
                                .append(",")
                                .append(reply.getClass());
                    getLogger().debug(logBuffer.toString());
                }
                return (Component)reply;
            } else {
                String key = protocol + type;
                String repClass = (String) classes.get( key );

                if (getLogger().isDebugEnabled()) {
                    logBuffer =
                        new StringBuffer(128)
                                .append("obtained repository: ")
                                .append(repClass)
                                .append(" to handle: ")
                                .append(protocol)
                                .append(",")
                                .append(type);
                    getLogger().debug( logBuffer.toString() );
                }

                // If default values have been set, create a new repository
                // configuration element using the default values
                // and the values in the selector.
                // If no default values, just use the selector.
                Configuration config;
                Configuration defConf = (Configuration)defaultConfigs.get(key);
                if ( defConf == null) {
                    config = repConf;
                }
                else {
                    config = new DefaultConfiguration(repConf.getName(),
                                                      repConf.getLocation());
                    copyConfig(defConf, (DefaultConfiguration)config);
                    copyConfig(repConf, (DefaultConfiguration)config);
                }

                try {
                    reply = (MailRepository) this.getClass().getClassLoader().loadClass(repClass).newInstance();
                    if (reply instanceof LogEnabled) {
                       setupLogger(reply);
                    }
                    if (reply instanceof Contextualizable) {
                        ((Contextualizable) reply).contextualize(context);
                    }
                    if (reply instanceof Composable) {
                        ((Composable) reply).compose( componentManager );
                    }
                    if (reply instanceof Configurable) {
                        ((Configurable) reply).configure(config);
                    }
                    if (reply instanceof Initializable) {
                        ((Initializable) reply).initialize();
                    }
                    repositories.put(repID, reply);
                    if (getLogger().isInfoEnabled()) {
                        logBuffer =
                            new StringBuffer(128)
                                .append("added repository: ")
                                .append(repID)
                                .append("->")
                                .append(repClass);
                        getLogger().info(logBuffer.toString());
                    }
                    return (Component)reply;
                } catch (Exception e) {
                    if (getLogger().isWarnEnabled()) {
                        getLogger().warn( "Exception while creating repository:" +
                                          e.getMessage(), e );
                    }
                    throw new
                        ComponentException("Cannot find or init repository",
                                           e);
                }
            }
        } catch( final ConfigurationException ce ) {
            throw new ComponentException( "Malformed configuration", ce );
        }
    }

    /**
     * <p>Returns a new name for a repository.</p>
     *
     * <p>Synchronized on the AvalonMailStore.class object to ensure
     * against duplication of the repository name</p>
     *
     * @return a new repository name
     */
    public static final String getName() {
        synchronized (AvalonMailStore.class) {
            return REPOSITORY_NAME + id++;
        }
    }

    /**
     * Returns the mail spool associated with this AvalonMailStore
     *
     * @return the mail spool
     *
     * @throws IllegalStateException if the inbound spool has not
     *                               yet been set
     */
    public SpoolRepository getInboundSpool() {
        if (inboundSpool != null) {
            return inboundSpool;
        } else {
            throw new IllegalStateException("Inbound spool not defined");
        }
    }

    /**
     * Returns whether the mail store has a repository corresponding to
     * the passed in hint.
     *
     * @param hint the Configuration object used to look up the repository
     *
     * @return whether the mail store has a repository corresponding to this hint
     */
    public boolean hasComponent( Object hint ) {
        Component comp = null;
        try {
            comp = select(hint);
        } catch(ComponentException ex) {
            if (getLogger().isErrorEnabled()) {
                getLogger().error("Exception AvalonMailStore.hasComponent-" + ex.toString());
            }
        }
        return (comp != null);
    }

    /**
     * Copies values from one config into another, overwriting duplicate attributes
     * and merging children.
     *
     * @param fromConfig the Configuration to be copied
     * @param toConfig the Configuration to which data is being copied
     */
    private void copyConfig(Configuration fromConfig, DefaultConfiguration toConfig)
    {
        // Copy attributes
        String[] attrs = fromConfig.getAttributeNames();
        for ( int i = 0; i < attrs.length; i++ ) {
            String attrName = attrs[i];
            String attrValue = fromConfig.getAttribute(attrName, null);
            toConfig.setAttribute(attrName, attrValue);
        }

        // Copy children
        Configuration[] children = fromConfig.getChildren();
        for ( int i = 0; i < children.length; i++ ) {
            Configuration child = children[i];
            String childName = child.getName();
            Configuration existingChild = toConfig.getChild(childName, false);
            if ( existingChild == null ) {
                toConfig.addChild(child);
            }
            else {
                copyConfig(child, (DefaultConfiguration)existingChild);
            }
        }

        // Copy value
        String val = fromConfig.getValue(null);
        if ( val != null ) {
            toConfig.setValue(val);
        }
    }

    /**
     * Return the <code>Component</code> when you are finished with it.  In this
     * implementation it does nothing
     *
     * @param component The Component we are releasing.
     */
    public void release(Component component) {}
}