-pluginpath* PARAMETERS

/**
 * Add the @link {@link Constants#PLUGINPATH} entries (which are file names)
 * to the class loader. If this file does not exist, and there is a
 * {@link Constants#PLUGINPATH_URL_ATTR} attribute then we download it first
 * from that url. You can then also specify a
 * {@link Constants#PLUGINPATH_SHA1_ATTR} attribute to verify the file.
 * 
 * @see PLUGINPATH
 * @param pluginPath
 *            the clauses for the plugin path
 * @param loader
 *            The class loader to extend
 */
private void loadPluginPath(Set<Object> instances, String pluginPath, CL loader) {
	Parameters pluginpath = new Parameters(pluginPath);

	nextClause: for (Entry<String,Attrs> entry : pluginpath.entrySet()) {

		File f = getFile(entry.getKey()).getAbsoluteFile();
		if (!f.isFile()) {

			//
			// File does not exist! Check if we need to download
			//

			String url = entry.getValue().get(PLUGINPATH_URL_ATTR);
			if (url != null) {
				try {

					trace("downloading %s to %s", url, f.getAbsoluteFile());
					URL u = new URL(url);
					URLConnection connection = u.openConnection();

					//
					// Allow the URLCOnnectionHandlers to interact with the
					// connection so they can sign it or decorate it with
					// a password etc.
					//
					for (Object plugin : instances) {
						if (plugin instanceof URLConnectionHandler) {
							URLConnectionHandler handler = (URLConnectionHandler) plugin;
							if (handler.matches(u))
								handler.handle(connection);
						}
					}

					//
					// Copy the url to the file
					//
					f.getParentFile().mkdirs();
					IO.copy(connection.getInputStream(), f);

					//
					// If there is a sha specified, we verify the download
					// of the
					// the file.
					//
					String digest = entry.getValue().get(PLUGINPATH_SHA1_ATTR);
					if (digest != null) {
						if (Hex.isHex(digest.trim())) {
							byte[] sha1 = Hex.toByteArray(digest);
							byte[] filesha1 = SHA1.digest(f).digest();
							if (!Arrays.equals(sha1, filesha1)) {
								error("Plugin path: %s, specified url %s and a sha1 but the file does not match the sha",
										entry.getKey(), url);
							}
						} else {
							error("Plugin path: %s, specified url %s and a sha1 '%s' but this is not a hexadecimal",
									entry.getKey(), url, digest);
						}
					}
				}
				catch (Exception e) {
					error("Failed to download plugin %s from %s, error %s", entry.getKey(), url, e);
					continue nextClause;
				}
			} else {
				error("No such file %s from %s and no 'url' attribute on the path so it can be downloaded",
						entry.getKey(), this);
				continue nextClause;
			}
		}
		trace("Adding %s to loader for plugins", f);
		try {
			loader.add(f.toURI().toURL());
		}
		catch (MalformedURLException e) {
			// Cannot happen since every file has a correct url
		}
	}
}