Java tutorial
/* * Copyright (c) 2011, Martijn Brinkers, Djigzo. * * This file is part of Djigzo email encryption. * * Djigzo is free software: you can redistribute it and/or modify * it under the terms of the GNU Affero General Public License * version 3, 19 November 2007 as published by the Free Software * Foundation. * * Djigzo is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU Affero General Public License for more details. * * You should have received a copy of the GNU Affero General Public * License along with Djigzo. If not, see <http://www.gnu.org/licenses/> * * Additional permission under GNU AGPL version 3 section 7 * * If you modify this Program, or any covered work, by linking or * combining it with aspectjrt.jar, aspectjweaver.jar, tyrex-1.0.3.jar, * freemarker.jar, dom4j.jar, mx4j-jmx.jar, mx4j-tools.jar, * spice-classman-1.0.jar, spice-loggerstore-0.5.jar, spice-salt-0.8.jar, * spice-xmlpolicy-1.0.jar, saaj-api-1.3.jar, saaj-impl-1.3.jar, * wsdl4j-1.6.1.jar (or modified versions of these libraries), * containing parts covered by the terms of Eclipse Public License, * tyrex license, freemarker license, dom4j license, mx4j license, * Spice Software License, Common Development and Distribution License * (CDDL), Common Public License (CPL) the licensors of this Program grant * you additional permission to convey the resulting work. */ package mitm.application.djigzo.james.mailets; import javax.mail.MessagingException; import mitm.application.djigzo.User; import mitm.application.djigzo.UserProperties; import mitm.application.djigzo.james.MailAddressUtils; import mitm.application.djigzo.service.SystemServices; import mitm.application.djigzo.workflow.UserWorkflow; import mitm.common.hibernate.DatabaseActionExecutor; import mitm.common.hibernate.DatabaseActionExecutorBuilder; import mitm.common.hibernate.SessionManager; import mitm.common.properties.HierarchicalPropertiesException; import mitm.common.security.password.PasswordGenerator; import org.apache.commons.lang.StringUtils; import org.apache.commons.lang.text.StrBuilder; import org.apache.mailet.Mail; import org.slf4j.Logger; import org.slf4j.LoggerFactory; /** * Mailet that generates a client secret for all recipients that do not yet have a client secret * * @author Martijn Brinkers * */ public class GenerateClientSecret extends AbstractDjigzoMailet { private final static Logger logger = LoggerFactory.getLogger(GenerateClientSecret.class); /* * The number of times a database action should be retried when a ConstraintViolation occurs */ private final static int ACTION_RETRIES = 3; /* * Generator used for generating the client secrets. */ private PasswordGenerator passwordGenerator; /* * manages database sessions */ private SessionManager sessionManager; /* * Used for adding and retrieving users */ private UserWorkflow userWorkflow; /* * Used to execute database actions in a transaction */ private DatabaseActionExecutor actionExecutor; /* * The length in bytes of the generated client secret */ private int clientSecretLength = 16; /* * Skip if the client secret was already set */ private boolean skipIfClientSecretSet = true; /* * The mailet initialization parameters used by this mailet. */ private enum Parameter { CLIENT_SECRET_LENGTH("clientSecretLength"), SKIP_IF_SECRET_SET("skipIfClientSecretSet"); private String name; private Parameter(String name) { this.name = name; } }; @Override protected Logger getLogger() { return logger; } @Override public void initMailet() throws MessagingException { super.initMailet(); clientSecretLength = getIntegerInitParameter(Parameter.CLIENT_SECRET_LENGTH.name, clientSecretLength); skipIfClientSecretSet = getBooleanInitParameter(Parameter.SKIP_IF_SECRET_SET.name, skipIfClientSecretSet); passwordGenerator = SystemServices.getPasswordGenerator(); sessionManager = SystemServices.getSessionManager(); userWorkflow = SystemServices.getUserWorkflow(); actionExecutor = DatabaseActionExecutorBuilder.createDatabaseActionExecutor(sessionManager); assert (actionExecutor != null); StrBuilder sb = new StrBuilder(); sb.append("clientSecretLength: "); sb.append(clientSecretLength); getLogger().info(sb.toString()); } protected void onHandleUserEvent(User user) throws MessagingException { UserProperties userProperties = user.getUserPreferences().getProperties(); try { /* * Check if the user does not yet have a client secret. This is required to prevent * a possible race condition. The check if the user has a secret is done with a matcher. * After the check, it can happen that a client secret was already created within a different * thread (hence the race condition). */ if (StringUtils.isEmpty(userProperties.getClientSecret()) || !skipIfClientSecretSet) { userProperties.setClientSecret(passwordGenerator.generatePassword(clientSecretLength)); /* * Since we have created a client secret, we need to make the user persistent */ userWorkflow.makePersistent(user); } } catch (HierarchicalPropertiesException e) { throw new MessagingException("Error creating client secret for user " + user.getEmail(), e); } } @Override public void serviceMail(Mail mail) { try { MailAddressHandler.HandleUserEventHandler eventHandler = new MailAddressHandler.HandleUserEventHandler() { @Override public void handleUser(User user) throws MessagingException { onHandleUserEvent(user); } }; MailAddressHandler mailAddressHandler = new MailAddressHandler(sessionManager, userWorkflow, actionExecutor, eventHandler, ACTION_RETRIES); mailAddressHandler.handleMailAddresses(MailAddressUtils.getRecipients(mail)); } catch (MessagingException e) { getLogger().error("Error generating client secrets.", e); } } }