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Smack/source/org/jivesoftware/smack/XMPPConnection.java
Florian Schmaus c6248ec000 SMACK-389 Plugable compression framework
This commit adds the ability to plug-in different compression handlers
for different compression methods. It is also possible to add more
then one handler for the same method. The order how the handlers are
added determines which handler is tried first for usage. This is used
for the 'zlib' compression method, which now can be either provided by
Java7 or by JZlib (just like it was done before).

git-svn-id: http://svn.igniterealtime.org/svn/repos/smack/trunk@13522 b35dd754-fafc-0310-a699-88a17e54d16e
2013-02-26 09:26:41 +00:00

1028 lines
38 KiB
Java

/**
* $RCSfile$
* $Revision$
* $Date$
*
* Copyright 2003-2007 Jive Software.
*
* All rights reserved. Licensed 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.jivesoftware.smack;
import org.jivesoftware.smack.compression.XMPPInputOutputStream;
import org.jivesoftware.smack.filter.PacketFilter;
import org.jivesoftware.smack.packet.Packet;
import org.jivesoftware.smack.packet.Presence;
import org.jivesoftware.smack.packet.XMPPError;
import org.jivesoftware.smack.util.StringUtils;
import javax.net.ssl.KeyManager;
import javax.net.ssl.KeyManagerFactory;
import javax.net.ssl.SSLContext;
import javax.net.ssl.SSLSocket;
import javax.security.auth.callback.Callback;
import javax.security.auth.callback.CallbackHandler;
import javax.security.auth.callback.PasswordCallback;
import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.ByteArrayInputStream;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.lang.reflect.Constructor;
import java.net.Socket;
import java.net.UnknownHostException;
import java.security.KeyStore;
import java.security.Provider;
import java.security.Security;
import java.util.Collection;
/**
* Creates a socket connection to a XMPP server. This is the default connection
* to a Jabber server and is specified in the XMPP Core (RFC 3920).
*
* @see Connection
* @author Matt Tucker
*/
public class XMPPConnection extends Connection {
/**
* The socket which is used for this connection.
*/
Socket socket;
String connectionID = null;
private String user = null;
private boolean connected = false;
// socketClosed is used concurrent
// by XMPPConnection, PacketReader, PacketWriter
private volatile boolean socketClosed = false;
/**
* Flag that indicates if the user is currently authenticated with the server.
*/
private boolean authenticated = false;
/**
* Flag that indicates if the user was authenticated with the server when the connection
* to the server was closed (abruptly or not).
*/
private boolean wasAuthenticated = false;
private boolean anonymous = false;
private boolean usingTLS = false;
PacketWriter packetWriter;
PacketReader packetReader;
Roster roster = null;
/**
* Collection of available stream compression methods offered by the server.
*/
private Collection<String> compressionMethods;
/**
* Set to true by packet writer if the server acknowledged the compression
*/
private boolean serverAckdCompression = false;
/**
* Creates a new connection to the specified XMPP server. A DNS SRV lookup will be
* performed to determine the IP address and port corresponding to the
* service name; if that lookup fails, it's assumed that server resides at
* <tt>serviceName</tt> with the default port of 5222. Encrypted connections (TLS)
* will be used if available, stream compression is disabled, and standard SASL
* mechanisms will be used for authentication.<p>
* <p/>
* This is the simplest constructor for connecting to an XMPP server. Alternatively,
* you can get fine-grained control over connection settings using the
* {@link #XMPPConnection(ConnectionConfiguration)} constructor.<p>
* <p/>
* Note that XMPPConnection constructors do not establish a connection to the server
* and you must call {@link #connect()}.<p>
* <p/>
* The CallbackHandler will only be used if the connection requires the client provide
* an SSL certificate to the server. The CallbackHandler must handle the PasswordCallback
* to prompt for a password to unlock the keystore containing the SSL certificate.
*
* @param serviceName the name of the XMPP server to connect to; e.g. <tt>example.com</tt>.
* @param callbackHandler the CallbackHandler used to prompt for the password to the keystore.
*/
public XMPPConnection(String serviceName, CallbackHandler callbackHandler) {
// Create the configuration for this new connection
super(new ConnectionConfiguration(serviceName));
config.setCompressionEnabled(false);
config.setSASLAuthenticationEnabled(true);
config.setDebuggerEnabled(DEBUG_ENABLED);
config.setCallbackHandler(callbackHandler);
}
/**
* Creates a new XMPP connection in the same way {@link #XMPPConnection(String,CallbackHandler)} does, but
* with no callback handler for password prompting of the keystore. This will work
* in most cases, provided the client is not required to provide a certificate to
* the server.
*
* @param serviceName the name of the XMPP server to connect to; e.g. <tt>example.com</tt>.
*/
public XMPPConnection(String serviceName) {
// Create the configuration for this new connection
super(new ConnectionConfiguration(serviceName));
config.setCompressionEnabled(false);
config.setSASLAuthenticationEnabled(true);
config.setDebuggerEnabled(DEBUG_ENABLED);
}
/**
* Creates a new XMPP connection in the same way {@link #XMPPConnection(ConnectionConfiguration,CallbackHandler)} does, but
* with no callback handler for password prompting of the keystore. This will work
* in most cases, provided the client is not required to provide a certificate to
* the server.
*
*
* @param config the connection configuration.
*/
public XMPPConnection(ConnectionConfiguration config) {
super(config);
}
/**
* Creates a new XMPP connection using the specified connection configuration.<p>
* <p/>
* Manually specifying connection configuration information is suitable for
* advanced users of the API. In many cases, using the
* {@link #XMPPConnection(String)} constructor is a better approach.<p>
* <p/>
* Note that XMPPConnection constructors do not establish a connection to the server
* and you must call {@link #connect()}.<p>
* <p/>
*
* The CallbackHandler will only be used if the connection requires the client provide
* an SSL certificate to the server. The CallbackHandler must handle the PasswordCallback
* to prompt for a password to unlock the keystore containing the SSL certificate.
*
* @param config the connection configuration.
* @param callbackHandler the CallbackHandler used to prompt for the password to the keystore.
*/
public XMPPConnection(ConnectionConfiguration config, CallbackHandler callbackHandler) {
super(config);
config.setCallbackHandler(callbackHandler);
}
public String getConnectionID() {
if (!isConnected()) {
return null;
}
return connectionID;
}
public String getUser() {
if (!isAuthenticated()) {
return null;
}
return user;
}
@Override
public synchronized void login(String username, String password, String resource) throws XMPPException {
if (!isConnected()) {
throw new IllegalStateException("Not connected to server.");
}
if (authenticated) {
throw new IllegalStateException("Already logged in to server.");
}
// Do partial version of nameprep on the username.
username = username.toLowerCase().trim();
String response;
if (config.isSASLAuthenticationEnabled() &&
saslAuthentication.hasNonAnonymousAuthentication()) {
// Authenticate using SASL
if (password != null) {
response = saslAuthentication.authenticate(username, password, resource);
}
else {
response = saslAuthentication
.authenticate(username, resource, config.getCallbackHandler());
}
}
else {
// Authenticate using Non-SASL
response = new NonSASLAuthentication(this).authenticate(username, password, resource);
}
// Set the user.
if (response != null) {
this.user = response;
// Update the serviceName with the one returned by the server
config.setServiceName(StringUtils.parseServer(response));
}
else {
this.user = username + "@" + getServiceName();
if (resource != null) {
this.user += "/" + resource;
}
}
// If compression is enabled then request the server to use stream compression
if (config.isCompressionEnabled()) {
useCompression();
}
// Indicate that we're now authenticated.
authenticated = true;
anonymous = false;
// Create the roster if it is not a reconnection or roster already created by getRoster()
if (this.roster == null) {
this.roster = new Roster(this);
}
if (config.isRosterLoadedAtLogin()) {
this.roster.reload();
}
// Set presence to online.
if (config.isSendPresence()) {
packetWriter.sendPacket(new Presence(Presence.Type.available));
}
// Stores the authentication for future reconnection
config.setLoginInfo(username, password, resource);
// If debugging is enabled, change the the debug window title to include the
// name we are now logged-in as.
// If DEBUG_ENABLED was set to true AFTER the connection was created the debugger
// will be null
if (config.isDebuggerEnabled() && debugger != null) {
debugger.userHasLogged(user);
}
}
@Override
public synchronized void loginAnonymously() throws XMPPException {
if (!isConnected()) {
throw new IllegalStateException("Not connected to server.");
}
if (authenticated) {
throw new IllegalStateException("Already logged in to server.");
}
String response;
if (config.isSASLAuthenticationEnabled() &&
saslAuthentication.hasAnonymousAuthentication()) {
response = saslAuthentication.authenticateAnonymously();
}
else {
// Authenticate using Non-SASL
response = new NonSASLAuthentication(this).authenticateAnonymously();
}
// Set the user value.
this.user = response;
// Update the serviceName with the one returned by the server
config.setServiceName(StringUtils.parseServer(response));
// If compression is enabled then request the server to use stream compression
if (config.isCompressionEnabled()) {
useCompression();
}
// Set presence to online.
packetWriter.sendPacket(new Presence(Presence.Type.available));
// Indicate that we're now authenticated.
authenticated = true;
anonymous = true;
// If debugging is enabled, change the the debug window title to include the
// name we are now logged-in as.
// If DEBUG_ENABLED was set to true AFTER the connection was created the debugger
// will be null
if (config.isDebuggerEnabled() && debugger != null) {
debugger.userHasLogged(user);
}
}
public Roster getRoster() {
// synchronize against login()
synchronized(this) {
// if connection is authenticated the roster is already set by login()
// or a previous call to getRoster()
if (!isAuthenticated() || isAnonymous()) {
if (roster == null) {
roster = new Roster(this);
}
return roster;
}
}
if (!config.isRosterLoadedAtLogin()) {
roster.reload();
}
// If this is the first time the user has asked for the roster after calling
// login, we want to wait for the server to send back the user's roster. This
// behavior shields API users from having to worry about the fact that roster
// operations are asynchronous, although they'll still have to listen for
// changes to the roster. Note: because of this waiting logic, internal
// Smack code should be wary about calling the getRoster method, and may need to
// access the roster object directly.
if (!roster.rosterInitialized) {
try {
synchronized (roster) {
long waitTime = SmackConfiguration.getPacketReplyTimeout();
long start = System.currentTimeMillis();
while (!roster.rosterInitialized) {
if (waitTime <= 0) {
break;
}
roster.wait(waitTime);
long now = System.currentTimeMillis();
waitTime -= now - start;
start = now;
}
}
}
catch (InterruptedException ie) {
// Ignore.
}
}
return roster;
}
public boolean isConnected() {
return connected;
}
public boolean isSecureConnection() {
return isUsingTLS();
}
public boolean isSocketClosed() {
return socketClosed;
}
public boolean isAuthenticated() {
return authenticated;
}
public boolean isAnonymous() {
return anonymous;
}
/**
* Closes the connection by setting presence to unavailable then closing the stream to
* the XMPP server. The shutdown logic will be used during a planned disconnection or when
* dealing with an unexpected disconnection. Unlike {@link #disconnect()} the connection's
* packet reader, packet writer, and {@link Roster} will not be removed; thus
* connection's state is kept.
*
* @param unavailablePresence the presence packet to send during shutdown.
*/
protected void shutdown(Presence unavailablePresence) {
// Set presence to offline.
if (packetWriter != null) {
packetWriter.sendPacket(unavailablePresence);
}
this.setWasAuthenticated(authenticated);
authenticated = false;
if (packetReader != null) {
packetReader.shutdown();
}
if (packetWriter != null) {
packetWriter.shutdown();
}
// Wait 150 ms for processes to clean-up, then shutdown.
try {
Thread.sleep(150);
}
catch (Exception e) {
// Ignore.
}
// Set socketClosed to true. This will cause the PacketReader
// and PacketWriter to ingore any Exceptions that are thrown
// because of a read/write from/to a closed stream.
// It is *important* that this is done before socket.close()!
socketClosed = true;
try {
socket.close();
} catch (Exception e) {
e.printStackTrace();
}
// In most cases the close() should be successful, so set
// connected to false here.
connected = false;
// Close down the readers and writers.
if (reader != null) {
try {
// Should already be closed by the previous
// socket.close(). But just in case do it explicitly.
reader.close();
}
catch (Throwable ignore) { /* ignore */ }
reader = null;
}
if (writer != null) {
try {
// Should already be closed by the previous
// socket.close(). But just in case do it explicitly.
writer.close();
}
catch (Throwable ignore) { /* ignore */ }
writer = null;
}
// Make sure that the socket is really closed
try {
// Does nothing if the socket is already closed
socket.close();
}
catch (Exception e) {
// Ignore.
}
saslAuthentication.init();
}
public synchronized void disconnect(Presence unavailablePresence) {
// If not connected, ignore this request.
if (packetReader == null || packetWriter == null) {
return;
}
shutdown(unavailablePresence);
if (roster != null) {
roster.cleanup();
roster = null;
}
wasAuthenticated = false;
packetWriter.cleanup();
packetWriter = null;
packetReader.cleanup();
packetReader = null;
}
public void sendPacket(Packet packet) {
if (!isConnected()) {
throw new IllegalStateException("Not connected to server.");
}
if (packet == null) {
throw new NullPointerException("Packet is null.");
}
packetWriter.sendPacket(packet);
}
/**
* Registers a packet interceptor with this connection. The interceptor will be
* invoked every time a packet is about to be sent by this connection. Interceptors
* may modify the packet to be sent. A packet filter determines which packets
* will be delivered to the interceptor.
*
* @param packetInterceptor the packet interceptor to notify of packets about to be sent.
* @param packetFilter the packet filter to use.
* @deprecated replaced by {@link Connection#addPacketInterceptor(PacketInterceptor, PacketFilter)}.
*/
public void addPacketWriterInterceptor(PacketInterceptor packetInterceptor,
PacketFilter packetFilter) {
addPacketInterceptor(packetInterceptor, packetFilter);
}
/**
* Removes a packet interceptor.
*
* @param packetInterceptor the packet interceptor to remove.
* @deprecated replaced by {@link Connection#removePacketInterceptor(PacketInterceptor)}.
*/
public void removePacketWriterInterceptor(PacketInterceptor packetInterceptor) {
removePacketInterceptor(packetInterceptor);
}
/**
* Registers a packet listener with this connection. The listener will be
* notified of every packet that this connection sends. A packet filter determines
* which packets will be delivered to the listener. Note that the thread
* that writes packets will be used to invoke the listeners. Therefore, each
* packet listener should complete all operations quickly or use a different
* thread for processing.
*
* @param packetListener the packet listener to notify of sent packets.
* @param packetFilter the packet filter to use.
* @deprecated replaced by {@link #addPacketSendingListener(PacketListener, PacketFilter)}.
*/
public void addPacketWriterListener(PacketListener packetListener, PacketFilter packetFilter) {
addPacketSendingListener(packetListener, packetFilter);
}
/**
* Removes a packet listener for sending packets from this connection.
*
* @param packetListener the packet listener to remove.
* @deprecated replaced by {@link #removePacketSendingListener(PacketListener)}.
*/
public void removePacketWriterListener(PacketListener packetListener) {
removePacketSendingListener(packetListener);
}
private void connectUsingConfiguration(ConnectionConfiguration config) throws XMPPException {
String host = config.getHost();
int port = config.getPort();
try {
if (config.getSocketFactory() == null) {
this.socket = new Socket(host, port);
}
else {
this.socket = config.getSocketFactory().createSocket(host, port);
}
}
catch (UnknownHostException uhe) {
String errorMessage = "Could not connect to " + host + ":" + port + ".";
throw new XMPPException(errorMessage, new XMPPError(
XMPPError.Condition.remote_server_timeout, errorMessage),
uhe);
}
catch (IOException ioe) {
String errorMessage = "XMPPError connecting to " + host + ":"
+ port + ".";
throw new XMPPException(errorMessage, new XMPPError(
XMPPError.Condition.remote_server_error, errorMessage), ioe);
}
socketClosed = false;
initConnection();
}
/**
* Initializes the connection by creating a packet reader and writer and opening a
* XMPP stream to the server.
*
* @throws XMPPException if establishing a connection to the server fails.
*/
private void initConnection() throws XMPPException {
boolean isFirstInitialization = packetReader == null || packetWriter == null;
if (!isFirstInitialization) {
compressionHandler = null;
serverAckdCompression = false;
}
// Set the reader and writer instance variables
initReaderAndWriter();
try {
if (isFirstInitialization) {
packetWriter = new PacketWriter(this);
packetReader = new PacketReader(this);
// If debugging is enabled, we should start the thread that will listen for
// all packets and then log them.
if (config.isDebuggerEnabled()) {
addPacketListener(debugger.getReaderListener(), null);
if (debugger.getWriterListener() != null) {
addPacketSendingListener(debugger.getWriterListener(), null);
}
}
}
else {
packetWriter.init();
packetReader.init();
}
// Start the packet writer. This will open a XMPP stream to the server
packetWriter.startup();
// Start the packet reader. The startup() method will block until we
// get an opening stream packet back from server.
packetReader.startup();
// Make note of the fact that we're now connected.
connected = true;
// Start keep alive process (after TLS was negotiated - if available)
packetWriter.startKeepAliveProcess();
if (isFirstInitialization) {
// Notify listeners that a new connection has been established
for (ConnectionCreationListener listener : getConnectionCreationListeners()) {
listener.connectionCreated(this);
}
}
else if (!wasAuthenticated) {
packetReader.notifyReconnection();
}
}
catch (XMPPException ex) {
// An exception occurred in setting up the connection. Make sure we shut down the
// readers and writers and close the socket.
if (packetWriter != null) {
try {
packetWriter.shutdown();
}
catch (Throwable ignore) { /* ignore */ }
packetWriter = null;
}
if (packetReader != null) {
try {
packetReader.shutdown();
}
catch (Throwable ignore) { /* ignore */ }
packetReader = null;
}
if (reader != null) {
try {
reader.close();
}
catch (Throwable ignore) { /* ignore */ }
reader = null;
}
if (writer != null) {
try {
writer.close();
}
catch (Throwable ignore) { /* ignore */}
writer = null;
}
if (socket != null) {
try {
socket.close();
}
catch (Exception e) { /* ignore */ }
socket = null;
}
this.setWasAuthenticated(authenticated);
authenticated = false;
connected = false;
throw ex; // Everything stoppped. Now throw the exception.
}
}
private void initReaderAndWriter() throws XMPPException {
try {
if (compressionHandler == null) {
reader =
new BufferedReader(new InputStreamReader(socket.getInputStream(), "UTF-8"));
writer = new BufferedWriter(
new OutputStreamWriter(socket.getOutputStream(), "UTF-8"));
}
else {
try {
OutputStream os = compressionHandler.getOutputStream(socket.getOutputStream());
writer = new BufferedWriter(new OutputStreamWriter(os, "UTF-8"));
InputStream is = compressionHandler.getInputStream(socket.getInputStream());
reader = new BufferedReader(new InputStreamReader(is, "UTF-8"));
}
catch (Exception e) {
e.printStackTrace();
compressionHandler = null;
reader = new BufferedReader(
new InputStreamReader(socket.getInputStream(), "UTF-8"));
writer = new BufferedWriter(
new OutputStreamWriter(socket.getOutputStream(), "UTF-8"));
}
}
}
catch (IOException ioe) {
throw new XMPPException(
"XMPPError establishing connection with server.",
new XMPPError(XMPPError.Condition.remote_server_error,
"XMPPError establishing connection with server."),
ioe);
}
// If debugging is enabled, we open a window and write out all network traffic.
initDebugger();
}
/***********************************************
* TLS code below
**********************************************/
/**
* Returns true if the connection to the server has successfully negotiated TLS. Once TLS
* has been negotiatied the connection has been secured.
*
* @return true if the connection to the server has successfully negotiated TLS.
*/
public boolean isUsingTLS() {
return usingTLS;
}
/**
* Notification message saying that the server supports TLS so confirm the server that we
* want to secure the connection.
*
* @param required true when the server indicates that TLS is required.
*/
void startTLSReceived(boolean required) {
if (required && config.getSecurityMode() ==
ConnectionConfiguration.SecurityMode.disabled) {
packetReader.notifyConnectionError(new IllegalStateException(
"TLS required by server but not allowed by connection configuration"));
return;
}
if (config.getSecurityMode() == ConnectionConfiguration.SecurityMode.disabled) {
// Do not secure the connection using TLS since TLS was disabled
return;
}
try {
writer.write("<starttls xmlns=\"urn:ietf:params:xml:ns:xmpp-tls\"/>");
writer.flush();
}
catch (IOException e) {
packetReader.notifyConnectionError(e);
}
}
/**
* The server has indicated that TLS negotiation can start. We now need to secure the
* existing plain connection and perform a handshake. This method won't return until the
* connection has finished the handshake or an error occured while securing the connection.
*
* @throws Exception if an exception occurs.
*/
void proceedTLSReceived() throws Exception {
SSLContext context = this.config.getCustomSSLContext();
KeyStore ks = null;
KeyManager[] kms = null;
PasswordCallback pcb = null;
if(config.getCallbackHandler() == null) {
ks = null;
} else if (context == null) {
//System.out.println("Keystore type: "+configuration.getKeystoreType());
if(config.getKeystoreType().equals("NONE")) {
ks = null;
pcb = null;
}
else if(config.getKeystoreType().equals("PKCS11")) {
try {
Constructor<?> c = Class.forName("sun.security.pkcs11.SunPKCS11").getConstructor(InputStream.class);
String pkcs11Config = "name = SmartCard\nlibrary = "+config.getPKCS11Library();
ByteArrayInputStream config = new ByteArrayInputStream(pkcs11Config.getBytes());
Provider p = (Provider)c.newInstance(config);
Security.addProvider(p);
ks = KeyStore.getInstance("PKCS11",p);
pcb = new PasswordCallback("PKCS11 Password: ",false);
this.config.getCallbackHandler().handle(new Callback[]{pcb});
ks.load(null,pcb.getPassword());
}
catch (Exception e) {
ks = null;
pcb = null;
}
}
else if(config.getKeystoreType().equals("Apple")) {
ks = KeyStore.getInstance("KeychainStore","Apple");
ks.load(null,null);
//pcb = new PasswordCallback("Apple Keychain",false);
//pcb.setPassword(null);
}
else {
ks = KeyStore.getInstance(config.getKeystoreType());
try {
pcb = new PasswordCallback("Keystore Password: ",false);
config.getCallbackHandler().handle(new Callback[]{pcb});
ks.load(new FileInputStream(config.getKeystorePath()), pcb.getPassword());
}
catch(Exception e) {
ks = null;
pcb = null;
}
}
KeyManagerFactory kmf = KeyManagerFactory.getInstance("SunX509");
try {
if(pcb == null) {
kmf.init(ks,null);
} else {
kmf.init(ks,pcb.getPassword());
pcb.clearPassword();
}
kms = kmf.getKeyManagers();
} catch (NullPointerException npe) {
kms = null;
}
}
// Verify certificate presented by the server
if (context == null) {
context = SSLContext.getInstance("TLS");
context.init(kms, new javax.net.ssl.TrustManager[] { new ServerTrustManager(getServiceName(), config) },
new java.security.SecureRandom());
}
Socket plain = socket;
// Secure the plain connection
socket = context.getSocketFactory().createSocket(plain,
plain.getInetAddress().getHostAddress(), plain.getPort(), true);
socket.setSoTimeout(0);
socket.setKeepAlive(true);
// Initialize the reader and writer with the new secured version
initReaderAndWriter();
// Proceed to do the handshake
((SSLSocket) socket).startHandshake();
//if (((SSLSocket) socket).getWantClientAuth()) {
// System.err.println("Connection wants client auth");
//}
//else if (((SSLSocket) socket).getNeedClientAuth()) {
// System.err.println("Connection needs client auth");
//}
//else {
// System.err.println("Connection does not require client auth");
// }
// Set that TLS was successful
usingTLS = true;
// Set the new writer to use
packetWriter.setWriter(writer);
// Send a new opening stream to the server
packetWriter.openStream();
}
/**
* Sets the available stream compression methods offered by the server.
*
* @param methods compression methods offered by the server.
*/
void setAvailableCompressionMethods(Collection<String> methods) {
compressionMethods = methods;
}
/**
* Returns the compression handler that can be used for one compression methods offered by the server.
*
* @return a instance of XMPPInputOutputStream or null if no suitable instance was found
*
*/
private XMPPInputOutputStream maybeGetCompressionHandler() {
if (compressionMethods != null) {
for (XMPPInputOutputStream handler : compressionHandlers) {
if (!handler.isSupported())
continue;
String method = handler.getCompressionMethod();
if (compressionMethods.contains(method))
return handler;
}
}
return null;
}
public boolean isUsingCompression() {
return compressionHandler != null && serverAckdCompression;
}
/**
* Starts using stream compression that will compress network traffic. Traffic can be
* reduced up to 90%. Therefore, stream compression is ideal when using a slow speed network
* connection. However, the server and the client will need to use more CPU time in order to
* un/compress network data so under high load the server performance might be affected.<p>
* <p/>
* Stream compression has to have been previously offered by the server. Currently only the
* zlib method is supported by the client. Stream compression negotiation has to be done
* before authentication took place.<p>
* <p/>
* Note: to use stream compression the smackx.jar file has to be present in the classpath.
*
* @return true if stream compression negotiation was successful.
*/
private boolean useCompression() {
// If stream compression was offered by the server and we want to use
// compression then send compression request to the server
if (authenticated) {
throw new IllegalStateException("Compression should be negotiated before authentication.");
}
if ((compressionHandler = maybeGetCompressionHandler()) != null) {
requestStreamCompression(compressionHandler.getCompressionMethod());
// Wait until compression is being used or a timeout happened
synchronized (this) {
try {
this.wait(SmackConfiguration.getPacketReplyTimeout() * 5);
}
catch (InterruptedException e) {
// Ignore.
}
}
return isUsingCompression();
}
return false;
}
/**
* Request the server that we want to start using stream compression. When using TLS
* then negotiation of stream compression can only happen after TLS was negotiated. If TLS
* compression is being used the stream compression should not be used.
*/
private void requestStreamCompression(String method) {
try {
writer.write("<compress xmlns='http://jabber.org/protocol/compress'>");
writer.write("<method>" + method + "</method></compress>");
writer.flush();
}
catch (IOException e) {
packetReader.notifyConnectionError(e);
}
}
/**
* Start using stream compression since the server has acknowledged stream compression.
*
* @throws Exception if there is an exception starting stream compression.
*/
void startStreamCompression() throws Exception {
serverAckdCompression = true;
// Initialize the reader and writer with the new secured version
initReaderAndWriter();
// Set the new writer to use
packetWriter.setWriter(writer);
// Send a new opening stream to the server
packetWriter.openStream();
// Notify that compression is being used
synchronized (this) {
this.notify();
}
}
/**
* Notifies the XMPP connection that stream compression was denied so that
* the connection process can proceed.
*/
void streamCompressionDenied() {
synchronized (this) {
this.notify();
}
}
/**
* Establishes a connection to the XMPP server and performs an automatic login
* only if the previous connection state was logged (authenticated). It basically
* creates and maintains a socket connection to the server.<p>
* <p/>
* Listeners will be preserved from a previous connection if the reconnection
* occurs after an abrupt termination.
*
* @throws XMPPException if an error occurs while trying to establish the connection.
* Two possible errors can occur which will be wrapped by an XMPPException --
* UnknownHostException (XMPP error code 504), and IOException (XMPP error code
* 502). The error codes and wrapped exceptions can be used to present more
* appropiate error messages to end-users.
*/
public void connect() throws XMPPException {
// Establishes the connection, readers and writers
connectUsingConfiguration(config);
// Automatically makes the login if the user was previouslly connected successfully
// to the server and the connection was terminated abruptly
if (connected && wasAuthenticated) {
// Make the login
try {
if (isAnonymous()) {
// Make the anonymous login
loginAnonymously();
}
else {
login(config.getUsername(), config.getPassword(),
config.getResource());
}
packetReader.notifyReconnection();
}
catch (XMPPException e) {
e.printStackTrace();
}
}
}
/**
* Sets whether the connection has already logged in the server.
*
* @param wasAuthenticated true if the connection has already been authenticated.
*/
private void setWasAuthenticated(boolean wasAuthenticated) {
if (!this.wasAuthenticated) {
this.wasAuthenticated = wasAuthenticated;
}
}
}