Java tutorial
// // GCALDaemon is an OS-independent Java program that offers two-way // synchronization between Google Calendar and various iCalalendar (RFC 2445) // compatible calendar applications (Sunbird, Rainlendar, iCal, Lightning, etc). // // Apache License // Version 2.0, January 2004 // http://www.apache.org/licenses/ // // Project home: // http://gcaldaemon.sourceforge.net // package org.gcaldaemon.core.mailterm; import java.io.File; import java.nio.charset.Charset; import java.util.LinkedList; import java.util.Set; import java.util.SortedMap; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.gcaldaemon.core.Configurator; import org.gcaldaemon.core.FilterMask; import org.gcaldaemon.core.GmailEntry; import org.gcaldaemon.core.GmailMessage; import org.gcaldaemon.core.GmailPool; import org.gcaldaemon.core.StringUtils; import org.gcaldaemon.logger.QuickWriter; import com.google.gdata.data.HtmlTextConstruct; /** * Gmail-based command line interface. * * Created: Jan 03, 2007 12:50:56 PM * * @author Andras Berkes */ public final class MailTerminal extends Thread { // --- CONSTANTS --- private static final String QUIT_COMMAND = "quit"; private static final byte COMMAND_NOT_FOUND = 0; private static final byte COMMAND_EXECUTED = 1; private static final byte QUIT_REQUESTED = 2; private static final long FAST_POLLING_TIMEOUT = 60000L; private static final long SCRIPT_TIMEOUT = 30000L; // --- LOGGER --- private static final Log log = LogFactory.getLog(MailTerminal.class); // --- VARIABLES --- private final Configurator configurator; private final long pollingTimeout; private final String username; private final String password; private final String subject; private final String encoding; private final File scriptDir; private final FilterMask[] addresses; // --- CONSTRUCTOR --- public MailTerminal(ThreadGroup mainGroup, Configurator configurator) throws Exception { super(mainGroup, "Mail terminal"); this.configurator = configurator; // Get inbox polling time long timeout = configurator.getConfigProperty(Configurator.MAILTERM_POLLING_GOOGLE, 10000L); if (timeout < 60000L) { log.warn("The fastest Gmail inbox polling period is '1 min'!"); timeout = 60000L; } pollingTimeout = timeout; // Get Gmail user username = configurator.getConfigProperty(Configurator.MAILTERM_GOOGLE_USERNAME, null); if (username == null) { throw new NullPointerException("Missing username (" + Configurator.MAILTERM_GOOGLE_USERNAME + ")!"); } // Get Gmail password password = configurator.getPasswordProperty(Configurator.MAILTERM_GOOGLE_PASSWORD); // Get subject of the command mails subject = configurator.getPasswordProperty(Configurator.MAILTERM_MAIL_SUBJECT); // Get script directory String path = configurator.getConfigProperty(Configurator.MAILTERM_DIR_PATH, "/scripts"); scriptDir = new File(path); if (!scriptDir.isDirectory()) { scriptDir.mkdirs(); if (!scriptDir.isDirectory()) { throw new Exception("Unable to read script directory (" + path + ")! Permission denied!"); } } // Get native console encoding String consoleEncoding = configurator.getConfigProperty(Configurator.MAILTERM_CONSOLE_ENCODING, StringUtils.US_ASCII); try { StringUtils.US_ASCII.getBytes(consoleEncoding); } catch (Exception unsupportedEncoding) { // Dump supported encodings SortedMap map = Charset.availableCharsets(); if (map != null) { Set set = map.keySet(); if (set != null) { String[] array = new String[set.size()]; set.toArray(array); QuickWriter writer = new QuickWriter(); writer.write("Invalid charset ("); writer.write(consoleEncoding); writer.write(")! Supported console encodings:\r\n"); for (int i = 0; i < array.length; i++) { writer.write(array[i]); if (i < array.length - 1) { writer.write(", "); } if (i % 6 == 5) { writer.write("\r\n"); } } log.warn(writer.toString().trim()); } } consoleEncoding = StringUtils.US_ASCII; } encoding = consoleEncoding; // Get acceptable e-mail addresses addresses = configurator.getFilterProperty(Configurator.MAILTERM_ALLOWED_ADDRESSES, true); // Start listener log.info("Mailterm service started successfully."); start(); } // --- DIRECTORY LISTENER LOOP --- public final void run() { try { sleep(5000L); } catch (InterruptedException interrupt) { log.info("Mailterm service stopped."); return; } for (;;) { try { // Borrow pooled Gmail connection GmailPool pool = configurator.getGmailPool(); byte responseType = COMMAND_NOT_FOUND; GmailEntry entry = null; try { entry = pool.borrow(username, password); // Receive mails responseType = receiveMails(entry); } finally { // Recycle pooled connection pool.recycle(entry); } // Shutdown mailterm if (responseType == QUIT_REQUESTED) { throw new InterruptedException(); } // Wait if (responseType == COMMAND_NOT_FOUND) { sleep(pollingTimeout); } else { sleep(FAST_POLLING_TIMEOUT); } } catch (InterruptedException interrupt) { log.info("Mailterm service stopped."); return; } catch (Exception poolException) { log.warn("Unexpected mailterm error!", poolException); log.debug("Please verify your username/password and IMAP settings!"); try { sleep(pollingTimeout); } catch (InterruptedException interrupt) { log.info("Mailterm service stopped."); return; } } } } // --- MAIL RECEIVER --- private final byte receiveMails(GmailEntry client) throws Exception { // Find new mails log.debug("Searching commands in mailbox..."); GmailMessage[] unreadMails = client.receive(subject); if (unreadMails == null || unreadMails.length == 0) { log.debug("Mailbox is empty or subject not found."); return COMMAND_NOT_FOUND; } // Read mails byte responseType = COMMAND_NOT_FOUND; GmailMessage message; for (int i = 0; i < unreadMails.length; i++) { message = unreadMails[i]; // Get reply address String replyAddress = message.from; // Check access by reply address if (addresses != null) { if (!isAddressMatch(replyAddress)) { log.warn("Request refused, forbidden e-mail address (" + replyAddress + ")!"); continue; } } // Get command String command = message.memo; if (command == null) { log.debug("Missing command body!"); continue; } HtmlTextConstruct html = new HtmlTextConstruct(command); command = html.getPlainText(); command = command.replace('\r', ' ').replace('\n', ' ').trim(); if (command.length() == 0) { log.debug("Missing command!"); continue; } log.debug("Executing command from " + replyAddress + " (" + command + ")..."); String reply; if (command.equals(QUIT_COMMAND)) { // Shutdown requested reply = "Mailterm service terminated. Bye!"; responseType = QUIT_REQUESTED; } else { // Parse command String[] args = parseLine(command); // Execute script ScriptRunner runner = new ScriptRunner(scriptDir, encoding, args); runner.join(SCRIPT_TIMEOUT); reply = runner.getScriptOutput(); if (responseType != QUIT_REQUESTED) { responseType = COMMAND_EXECUTED; } } // Send reply log.debug("Command output:\r\n" + reply); client.send(replyAddress, null, null, "Re:" + subject, "<pre>" + reply.trim() + "</pre>", true); // Wait Thread.sleep(500); } return responseType; } private final boolean isAddressMatch(String string) { for (int i = 0; i < addresses.length; i++) { if (addresses[i].match(string)) { return true; } } return false; } // --- COMMAND LINE PARSER --- /** * Splitting a string into a command-array. * * <BR> * <BR> * word1 word2 word3 -> "word1", "word2", "word3" <BR> * word1 word2="word3 'abc' def" -> "word1", "word2", "word3 'abc' def" <BR> * 'wo"rd1'="word2" word3 -> "wo\"rd1", "word2", "word3" <BR> * etc. * * @param cmdLine * @return String[] */ private static final String[] parseLine(String cmdLine) { char delimiter = ' '; boolean inToken = false; QuickWriter writer = new QuickWriter(100); LinkedList tokens = new LinkedList(); for (int i = 0; i < cmdLine.length(); i++) { char c = cmdLine.charAt(i); if (inToken) { if (c == delimiter || (delimiter == ' ' && c == '=')) { tokens.add(writer.toString()); writer.flush(); if (c == '-') { writer.write(c); } inToken = false; continue; } writer.write(c); } else { if (c == '\'') { delimiter = '\''; inToken = true; } else { if (c == '"') { delimiter = '"'; inToken = true; } else if (c == ' ') { // Skip } else { delimiter = ' '; writer.write(c); inToken = true; } } } if (i == cmdLine.length() - 1 && writer.length() != 0) { tokens.add(writer.toString()); } } String[] array = new String[tokens.size()]; tokens.toArray(array); return array; } }