Source:
<code>private void initializeClient(URI uri, String fileSystemName, String accountName, boolean isSecure) throws IOException { if (this.client != null) { return; } final URIBuilder uriBuilder = getURIBuilder(accountName, isSecure); final String url = uriBuilder.toString() + AbfsHttpConstants.FORWARD_SLASH + fileSystemName; URL baseUrl; try { baseUrl = new URL(url); } catch (MalformedURLException e) { throw new InvalidUriException(uri.toString()); } SharedKeyCredentials creds = null; AccessTokenProvider tokenProvider = null; AuthType authType = abfsConfiguration.getAuthType(accountName); AbfsAuthorizer authorizer = abfsConfiguration.getAbfsAuthorizer(); if ((authorizer == null) || ((authorizer.getAuthType() != AuthType.SAS))) { switch (authType) { case SharedKey: LOG.trace("Fetching SharedKey credentials"); int dotIndex = accountName.indexOf(AbfsHttpConstants.DOT); if (dotIndex <= 0) { throw new InvalidUriException( uri.toString() + " - account name is not fully qualified."); } creds = new SharedKeyCredentials(accountName.substring(0, dotIndex), abfsConfiguration.getStorageAccountKey()); break; case Custom: case OAuth: LOG.trace("Fetching token provider"); tokenProvider = abfsConfiguration.getTokenProvider(); ExtensionHelper .bind(tokenProvider, uri, abfsConfiguration.getRawConfiguration()); break; case SAS: throw new UnsupportedOperationException( <START> "There is no " + "Authorizer configured"); <END> case None: throw new UnsupportedOperationException( "No authentication means " + "configured"); } } LOG.trace("Initializing AbfsClient for {}", baseUrl); this.client = new AbfsClient(baseUrl, creds, abfsConfiguration, new ExponentialRetryPolicy(abfsConfiguration.getMaxIoRetries()), tokenProvider, abfsPerfTracker); LOG.trace("AbfsClient init complete"); }</code><technical_language>nit: join strings</technical_language>

Target:
private void initializeClient(URI uri, String fileSystemName, String accountName, boolean isSecure) throws IOException { if (this.client != null) { return; } final URIBuilder uriBuilder = getURIBuilder(accountName, isSecure); final String url = uriBuilder.toString() + AbfsHttpConstants.FORWARD_SLASH + fileSystemName; URL baseUrl; try { baseUrl = new URL(url); } catch (MalformedURLException e) { throw new InvalidUriException(uri.toString()); } SharedKeyCredentials creds = null; AccessTokenProvider tokenProvider = null; SASTokenProvider sasTokenProvider = null; if (authType == AuthType.SharedKey) { LOG.trace("Fetching SharedKey credentials"); int dotIndex = accountName.indexOf(AbfsHttpConstants.DOT); if (dotIndex <= 0) { throw new InvalidUriException( uri.toString() + " - account name is not fully qualified."); } creds = new SharedKeyCredentials(accountName.substring(0, dotIndex), abfsConfiguration.getStorageAccountKey()); } else if (authType == AuthType.SAS) { LOG.trace("Fetching SAS token provider"); sasTokenProvider = abfsConfiguration.getSASTokenProvider(); } else { LOG.trace("Fetching token provider"); tokenProvider = abfsConfiguration.getTokenProvider(); ExtensionHelper.bind(tokenProvider, uri, abfsConfiguration.getRawConfiguration()); } LOG.trace("Initializing AbfsClient for {}", baseUrl); if (tokenProvider != null) { this.client = new AbfsClient(baseUrl, creds, abfsConfiguration, new ExponentialRetryPolicy(abfsConfiguration.getMaxIoRetries()), tokenProvider, abfsPerfTracker); } else { this.client = new AbfsClient(baseUrl, creds, abfsConfiguration, new ExponentialRetryPolicy(abfsConfiguration.getMaxIoRetries()), sasTokenProvider, abfsPerfTracker); } LOG.trace("AbfsClient init complete"); }