Struts框架结构的Java Web开发技术基础与实践教程》上

/* * $Header: /cvsroot/struts/logon/WEB-INF/src/java/app/UserDirectory.java,v 1.1.1.1 2002/08/15 15:50:56 thusted Exp $ * $Revision: 1.1.1.1 $ * $Date: 2002/08/15 15:50:56 $ * * ==================================================================== * * The Apache Software License, Version 1.1 * * Copyright (c) 1999 The Apache Software Foundation. All rights * reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in * the documentation and/or other materials provided with the * distribution. * * 3. The end-user documentation included with the redistribution, if * any, must include the following acknowlegement: * "This product includes software developed by the * Apache Software Foundation (http://www.apache.org/)." * Alternately, this acknowlegement may appear in the software itself, * if and wherever such third-party acknowlegements normally appear. * * 4. The names "The Jakarta Project", "Tomcat", and "Apache Software * Foundation" must not be used to endorse or promote products derived * from this software without prior written permission. For written * permission, please contact apache@apache.org. * * 5. Products derived from this software may not be called "Apache" * nor may "Apache" appear in their names without prior written * permission of the Apache Group. * * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE * DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * ==================================================================== * * This software consists of voluntary contributions made by many * individuals on behalf of the Apache Software Foundation. For more * information on the Apache Software Foundation, please see * <http://www.apache.org/>. * */ /** * Implementation of <strong>Action</strong> that validates a user * logon. * <p> * :TODO: Javadocs. * * @todo Javadocs * @author George Franciscus * @version $Revision: 1.1.1.1 $ $Date: 2002/08/15 15:50:56 $ */ package app; import java.io.IOException; import java.io.InputStream; import java.io.FileOutputStream; import java.util.Enumeration; import java.util.Properties; public class UserDirectory { /** * */ private static final String UserDirectoryFile = "resources/users.properties"; /** * */ private static final String UserDirectoryHeader = "${user}=${password}"; /** * */ private static UserDirectory userDirectory = null; /** * */ private static Properties p; /** * */ private UserDirectory() throws UserDirectoryException { java.io.InputStream i = null; p = null; i = this.getClass().getClassLoader(). getResourceAsStream(UserDirectoryFile); if (null==i) { throw new UserDirectoryException(); } else { try { p = new Properties(); p.load(i); i.close(); } catch (java.io.IOException e) { p = null; System.out.println(e.getMessage()); throw new UserDirectoryException(); } finally { i = null; } } // end else } // end UserDirectory /** * */ public static UserDirectory getInstance() throws UserDirectoryException { if (null==userDirectory) { userDirectory = new UserDirectory(); } return userDirectory; } /** * Transform id so that it will match any conventions used by user * directory. The default implementation forces the id to * uppercase. Does <b>not</b> expect the userId to be null and * will throw a NPE if it is. * * @exception Throws Null Pointer Exception if userId is null. */ public String fixId(String userId) { return userId.toUpperCase(); } /** * */ public boolean isValidPassword(String userId, String password) { // no null passwords if (null==password) return false; // conform userId to uppercase String _userId = fixId(userId); // no passwords for non-users if (!isUserExist(_userId)) return false; // does password match user's password return (password.equals(getPassword(_userId))); } /** * */ public boolean isUserExist(String userId) { // no null users if (null==userId) return false; // if not null, it's a user return !(null==p.getProperty(userId)); } /** * */ public String getPassword(String userId) { return p.getProperty(userId); } /** * */ public Enumeration getUserIds() { return p.propertyNames(); } /** * */ public void setUser(String userId, String password) throws UserDirectoryException { // no nulls if ((null==userId) || (null==password)) { throw new UserDirectoryException(); } try { // conform userId to uppercase when stored p.put(fixId(userId), password); p.store(new FileOutputStream(UserDirectoryFile), UserDirectoryHeader); } catch (IOException e) { throw new UserDirectoryException(); } } } // end UserDirectory