Java tutorial
/* * DavMail POP/IMAP/SMTP/CalDav/LDAP Exchange Gateway * Copyright (C) 2009 Mickael Guessant * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version 2 * of the License, or (at your option) any later version. * * This program 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 General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */ package davmail; import davmail.exception.DavMailException; import davmail.exchange.ExchangeSession; import davmail.ui.tray.DavGatewayTray; import org.apache.commons.codec.binary.Base64; import java.io.*; import java.net.Socket; /** * Generic connection common to pop3 and smtp implementations */ public class AbstractConnection extends Thread { protected enum State { INITIAL, LOGIN, USER, PASSWORD, AUTHENTICATED, STARTMAIL, RECIPIENT, MAILDATA } protected static class LineReaderInputStream extends PushbackInputStream { final String encoding; /** * @inheritDoc */ protected LineReaderInputStream(InputStream in, String encoding) { super(in); if (encoding == null) { this.encoding = "ASCII"; } else { this.encoding = encoding; } } public String readLine() throws IOException { ByteArrayOutputStream baos = null; int b; while ((b = read()) > -1) { if (b == '\r') { int next = read(); if (next != '\n') { unread(next); } break; } else if (b == '\n') { break; } if (baos == null) { baos = new ByteArrayOutputStream(); } baos.write(b); } if (baos != null) { return new String(baos.toByteArray(), encoding); } else { return null; } } /** * Read byteSize bytes from inputStream, return content as String. * * @param byteSize content size * @return content * @throws IOException on error */ public String readContentAsString(int byteSize) throws IOException { return new String(readContent(byteSize), encoding); } /** * Read byteSize bytes from inputStream, return content as byte array. * * @param byteSize content size * @return content * @throws IOException on error */ public byte[] readContent(int byteSize) throws IOException { byte[] buffer = new byte[byteSize]; int startIndex = 0; int count = 0; while (count >= 0 && startIndex < byteSize) { count = in.read(buffer, startIndex, byteSize - startIndex); startIndex += count; } if (startIndex < byteSize) { throw new DavMailException("EXCEPTION_END_OF_STREAM"); } return buffer; } } protected final Socket client; protected LineReaderInputStream in; protected OutputStream os; // user name and password initialized through connection protected String userName; protected String password; // connection state protected State state = State.INITIAL; // Exchange session proxy protected ExchangeSession session; /** * Only set the thread name and socket * * @param name thread type name * @param clientSocket client socket */ public AbstractConnection(String name, Socket clientSocket) { super(name + '-' + clientSocket.getPort()); this.client = clientSocket; setDaemon(true); } /** * Initialize the streams and set thread name. * * @param name thread type name * @param clientSocket client socket * @param encoding socket stream encoding */ public AbstractConnection(String name, Socket clientSocket, String encoding) { super(name + '-' + clientSocket.getPort()); this.client = clientSocket; try { in = new LineReaderInputStream(client.getInputStream(), encoding); os = new BufferedOutputStream(client.getOutputStream()); } catch (IOException e) { close(); DavGatewayTray.error(new BundleMessage("LOG_EXCEPTION_GETTING_SOCKET_STREAMS"), e); } } /** * Send message to client followed by CRLF. * * @param message message * @throws IOException on error */ public void sendClient(String message) throws IOException { sendClient(null, message); } /** * Send prefix and message to client followed by CRLF. * * @param prefix prefix * @param message message * @throws IOException on error */ public void sendClient(String prefix, String message) throws IOException { if (prefix != null) { os.write(prefix.getBytes()); DavGatewayTray.debug(new BundleMessage("LOG_SEND_CLIENT_PREFIX_MESSAGE", prefix, message)); } else { DavGatewayTray.debug(new BundleMessage("LOG_SEND_CLIENT_MESSAGE", message)); } os.write(message.getBytes()); os.write((char) 13); os.write((char) 10); os.flush(); } /** * Send only bytes to client. * * @param messageBytes content * @throws IOException on error */ public void sendClient(byte[] messageBytes) throws IOException { sendClient(messageBytes, 0, messageBytes.length); } /** * Send only bytes to client. * * @param messageBytes content * @param offset the start offset in the data. * @param length the number of bytes to write. * @throws IOException on error */ public void sendClient(byte[] messageBytes, int offset, int length) throws IOException { //StringBuffer logBuffer = new StringBuffer("> "); //logBuffer.append(new String(messageBytes, offset, length)); //DavGatewayTray.debug(logBuffer.toString()); os.write(messageBytes, offset, length); os.flush(); } /** * Read a line from the client connection. * Log message to logger * * @return command line or null * @throws IOException when unable to read line */ public String readClient() throws IOException { String line = in.readLine(); if (line != null) { if (line.startsWith("PASS")) { DavGatewayTray.debug(new BundleMessage("LOG_READ_CLIENT_PASS")); // SMTP LOGIN } else if (line.startsWith("AUTH LOGIN ")) { DavGatewayTray.debug(new BundleMessage("LOG_READ_CLIENT_AUTH_LOGIN")); // IMAP LOGIN } else if (state == State.INITIAL && line.indexOf(' ') >= 0 && line.substring(line.indexOf(' ') + 1).toUpperCase().startsWith("LOGIN")) { DavGatewayTray.debug(new BundleMessage("LOG_READ_CLIENT_LOGIN")); } else if (state == State.PASSWORD) { DavGatewayTray.debug(new BundleMessage("LOG_READ_CLIENT_PASSWORD")); // HTTP Basic Authentication } else if (line.startsWith("Authorization:")) { DavGatewayTray.debug(new BundleMessage("LOG_READ_CLIENT_AUTHORIZATION")); } else if (line.startsWith("AUTH PLAIN")) { DavGatewayTray.debug(new BundleMessage("LOG_READ_CLIENT_AUTH_PLAIN")); } else { DavGatewayTray.debug(new BundleMessage("LOG_READ_CLIENT_LINE", line)); } } DavGatewayTray.switchIcon(); return line; } /** * Close client connection, streams and Exchange session . */ public void close() { if (in != null) { try { in.close(); } catch (IOException e2) { DavGatewayTray.warn(new BundleMessage("LOG_EXCEPTION_CLOSING_CLIENT_INPUT_STREAM"), e2); } } if (os != null) { try { os.close(); } catch (IOException e2) { DavGatewayTray.warn(new BundleMessage("LOG_EXCEPTION_CLOSING_CLIENT_OUTPUT_STREAM"), e2); } } try { client.close(); } catch (IOException e2) { DavGatewayTray.warn(new BundleMessage("LOG_EXCEPTION_CLOSING_CLIENT_SOCKET"), e2); } } protected String base64Encode(String value) { return new String(new Base64().encode(value.getBytes())); } protected String base64Decode(String value) { return new String(new Base64().decode(value.getBytes())); } }