Java tutorial
/* * Licensed to the Apache Software Foundation (ASF) under one or more * contributor license agreements. See the NOTICE file distributed with * this work for additional information regarding copyright ownership. * The ASF licenses this file to You under the Apache License, Version 2.0 * (the "License"); you may not use this file except in compliance with * the License. You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package org.apache.commons.vfs2.util; import org.apache.commons.vfs2.FileSystemOptions; import org.apache.commons.vfs2.UserAuthenticationData; import org.apache.commons.vfs2.UserAuthenticator; import org.apache.commons.vfs2.impl.DefaultFileSystemConfigBuilder; /** * Helps with authentication. */ public final class UserAuthenticatorUtils { private UserAuthenticatorUtils() { } /** * Gets data of given type from the UserAuthenticationData or null if there is no data or data * of this type available. * * @param data The UserAuthenticationData. * @param type The type of the element to retrieve. * @param overriddenValue The default value. * @return The data of the given type as a character array or null if the data is not available. */ public static char[] getData(final UserAuthenticationData data, final UserAuthenticationData.Type type, final char[] overriddenValue) { if (overriddenValue != null) { return overriddenValue; } if (data == null) { return null; } return data.getData(type); } /** * Authenticates if there is an authenticator, else returns null. * * @param opts The FileSystemOptions. * @param authenticatorTypes An array of types describing the data to be retrieved. * @return A UserAuthenticationData object containing the data requested. */ public static UserAuthenticationData authenticate(final FileSystemOptions opts, final UserAuthenticationData.Type[] authenticatorTypes) { final UserAuthenticator auth = DefaultFileSystemConfigBuilder.getInstance().getUserAuthenticator(opts); return authenticate(auth, authenticatorTypes); } /** * Authenticates if there is an authenticator, else returns null. * * @param auth The UserAuthenticator. * @param authenticatorTypes An array of types describing the data to be retrieved. * @return A UserAuthenticationData object containing the data requested. */ public static UserAuthenticationData authenticate(final UserAuthenticator auth, final UserAuthenticationData.Type[] authenticatorTypes) { if (auth == null) { return null; } return auth.requestAuthentication(authenticatorTypes); } /** * Converts a string to a char array (null-safe). * * @param string The String to convert. * @return The character array. */ public static char[] toChar(final String string) { if (string == null) { return null; } return string.toCharArray(); } /** * Cleans up the data in the UerAuthenticationData (null-safe). * * @param authData The UserAuthenticationDAta. */ public static void cleanup(final UserAuthenticationData authData) { if (authData == null) { return; } authData.cleanup(); } /** * Converts the given data to a string (null-safe). * * @param data A character array containing the data to convert to a String. * @return The String. */ public static String toString(final char[] data) { if (data == null) { return null; } return new String(data); } }