networkservercontrolimpl.java

来自「derby database source code.good for you.」· Java 代码 · 共 2,300 行 · 第 1/5 页

			consolePropertyMessage("DRDA_Usage"+i+".I");
		} catch (Exception e) {}	// ignore exceptions - there shouldn't be any
	}

	/**
	 * Set connection pool parameters for a database
	 *
	 * @param database	database parameters applied to
	 * @param min		minimum number of connections, if 0, pooled connections not used
	 *						if -1, use default						
	 * @param max		maximum number of connections, if 0, pooled connections 
	 *						created when no free connection available, if -1, 
	 *						use default
	 * @param host		machine network server is running on, if null, localhost is used
	 * @param portNumber	port number server is to use, if <= 0, default port number
	 *			is used
	 *
	 * @exception Exception	throws an exception if an error occurs
	 */
	protected void setConnectionPoolParameters(String database, int min, int max,
		String host, int portNumber)
		throws Exception
	{
		consolePropertyMessage("DRDA_NotImplemented.S", "conpool");
	}

	/**
	 * Set default connection pool parameters 
	 *
	 * @param min		minimum number of connections, if 0, pooled connections not used
	 *						if -1, use default
	 * @param max		maximum number of connections, if 0, pooled connections 
	 *						created when no free connection available
	 *						if -1, use default
	 * @param host		machine network server is running on, if null, localhost is used
	 * @param portNumber	port number server is to use, if <= 0, default port number
	 *			is used
	 *
	 * @exception Exception	throws an exception if an error occurs
	 */
	protected void setConnectionPoolParameters(int min, int max, String host, 
			int portNumber) throws Exception
	{
		consolePropertyMessage("DRDA_NotImplemented.S", "conpool");
	}

	/**
	 * Connect to  network server and set connection maxthread parameter
	 *
	 * @param max		maximum number of connections, if 0, connections 
	 *						created when no free connection available
	 *						if -1, use default
	 *
	 * @exception Exception	throws an exception if an error occurs
	 */
	public void netSetMaxThreads(int max) throws Exception
	{
		setUpSocket();
		writeCommandHeader(COMMAND_MAXTHREADS);
		commandOs.writeInt(max);
		send();
		readResult();
		int newval = readInt();
		consolePropertyMessage("DRDA_MaxThreadsChange.I", 
 					new Integer(newval).toString());
	}

	/**
	 * Set network server connection timeslice parameter
	 *
	 * @param timeslice	amount of time given to each session before yielding to 
	 *						another session, if 0, never yield. if -1, use default.
	 *
	 * @exception Exception	throws an exception if an error occurs
	 */
	public void netSetTimeSlice(int timeslice)
		throws Exception
	{
		setUpSocket();
		writeCommandHeader(COMMAND_TIMESLICE);
		commandOs.writeInt(timeslice);
		send();
		readResult();
		int newval = readInt();
		consolePropertyMessage("DRDA_TimeSliceChange.I", 
									   new Integer(newval).toString());
	}

	/**
	 * Get current properties
	 *
	 * @return Properties object containing properties
	 * @exception Exception	throws an exception if an error occurs
	 */
	public Properties getCurrentProperties() 
		throws Exception
	{
		setUpSocket();
		writeCommandHeader(COMMAND_PROPERTIES);
		send();
		byte [] val = readBytesReply("DRDA_PropertyError.S");
		Properties p = new Properties();
		try {
			ByteArrayInputStream bs = new ByteArrayInputStream(val);
			p.load(bs);
		} catch (IOException io) {
			consolePropertyMessage("DRDA_IOException.S", 
						io.getMessage());
		}
		return p;
	}

	/**
	 * Set a thread name to be something that is both meaningful and unique (primarily
	 * for debugging purposes).
	 *
	 * @param thrd An instance of a Thread object that still has its default
	 *  thread name (as generated by the jvm Thread constructor).  This should
	 *  always be of the form "Thread-N", where N is a unique thread id
	 *  generated by the jvm.  Ex. "Thread-0", "Thread-1", etc.
	 *
	 * @return The received thread's name has been set to a new string of the form
	 *  [newName + "_n"], where 'n' is a unique thread id originally generated
	 *  by the jvm Thread constructor.  If the default name of the thread has
	 *  been changed before getting here, then nothing is done.
	 *
	 **/
	public static void setUniqueThreadName(Thread thrd, String newName) {

		// First, pull off the unique thread id already found in thrd's default name;
		// we do so by searching for the '-' character, and then counting everything
		// after it as a N.
		if (thrd.getName().indexOf("Thread-") == -1) {
		// default name has been changed; don't do anything.
			return;
		}
		else {
			String oldName = thrd.getName();
			thrd.setName(newName + "_" +
			  oldName.substring(oldName.indexOf("-")+1, oldName.length()));
		} // end else.

		return;

	}

	/*******************************************************************************/
	/*        Protected methods                                                    */
	/*******************************************************************************/
	/**
	 * Remove session from session table
	 *
	 * @param sessionid 	id of session to be removed
	 */
	protected void removeFromSessionTable(int sessionid)
	{
		sessionTable.remove(new Integer(sessionid));
	}

	/**
	 * 	processCommands reads and processes NetworkServerControlImpl commands sent
	 * 	to the network server over the socket.  The protocol used is
	 * 		4 bytes 	- String CMD:
	 * 		2 bytes		- Protocol version
	 *		1 byte		- length of locale (0 for default)
	 *			n bytes - locale
	 *		1 byte		- length of codeset (0 for default)
	 *			n bytes - codeset
	 * 		1 byte		- command
	 * 		n bytes		- parameters for the command
	 * 	The server returns
	 *		4 bytes		- String RPY:
	 *	for most commands
	 *		1 byte		- command result, 0 - OK, 1 - warning, 2 - error
	 *	 if warning or error
	 *		1 bytes		- length of message key
	 *		n bytes		- message key
	 *		1 byte		- number of parameters to message
	 *		{2 bytes		- length of parameter
	 *		n bytes		- parameter} for each parameter
	 *  for sysinfo
	 *		1 byte		- command result, 0 - OK, 1 - warning, 2 - error
	 *   if OK 
	 *		2 bytes		- length of sysinfo
	 *		n bytes		- sysinfo
	 *		
	 * 		
	 * 	Note, the 3rd byte of the command must not be 'D0' to distinquish it 
	 *	from DSS structures.
	 * 	The protocol for the parameters for each command follows:
	 *
	 * 	Command: trace <connection id> {on | off}
	 * 	Protocol:
	 * 		4 bytes		- connection id - connection id of 0 means all sessions
	 * 		1 byte		- 0 off, 1 on
	 * 
	 * 	Command: logConnections {on | off}
	 * 	Protocol:
	 * 		1 byte		- 0 off, 1 on
	 * 
	 * 	Command: shutdown
	 * 	No parameters
	 * 
	 * 	Command: sysinfo
	 * 	No parameters
	 * 
	 * 	Command: dbstart
	 * 	Protocol:
	 * 		2 bytes		- length of database name
	 * 		n bytes		- database name
	 * 		2 bytes		- length of boot password
	 * 		n bytes		- boot password 
	 * 		2 bytes		- length of encryption algorithm
	 * 		n bytes		- encryption algorithm
	 * 		2 bytes		- length of encryption provider
	 * 		n bytes		- encryption provider
	 * 		2 bytes		- length of user name
	 * 		n bytes		- user name
	 * 		2 bytes		- length of password
	 * 		n bytes		- password
	 *
	 * 	Command: dbshutdown
	 * 	Protocol:
	 * 		2 bytes		- length of database name
	 * 		n bytes		- database name
	 * 		2 bytes		- length of user name
	 * 		n bytes		- user name
	 * 		2 bytes		- length of password
	 * 		n bytes		- password
	 *
	 * 	Command: connpool
	 * 	Protocol:
	 * 		2 bytes		- length of database name, if 0, default for all databases
	 *						is set
	 * 		n bytes		- database name
	 *		2 bytes		- minimum number of connections, if 0, connection pool not used
	 *						if value is -1 use default
	 *		2 bytes		- maximum number of connections, if 0, connections are created
	 *						as needed, if value is -1 use default
	 *
	 * 	Command: maxthreads
	 * 	Protocol:
	 *		2 bytes		- maximum number of threads
	 *
	 * 	Command: timeslice 
	 * 	Protocol:
	 *		4 bytes		- timeslice value
	 *
	 * 	Command: tracedirectory
	 * 	Protocol:
	 * 		2 bytes		- length of directory name
	 * 		n bytes		- directory name
	 *
	 *	Command: test connection
	 * 	Protocol:
	 * 		2 bytes		- length of database name if 0, just the connection
	 *						to the network server is tested and user name and 
	 *						password aren't sent
	 * 		n bytes		- database name
	 * 		2 bytes		- length of user name (optional)
	 * 		n bytes		- user name
	 * 		2 bytes		- length of password  (optional)
	 * 		n bytes		- password
	 *
	 *	The calling routine is synchronized so that multiple threads don't clobber each
	 * 	other. This means that configuration commands will be serialized.
	 * 	This shouldn't be a problem since they should be fairly rare.
	 * 		
	 * @param reader	input reader for command
	 * @param writer output writer for command
	 * @param session	session information
	 *
	 * @exception Throwable	throws an exception if an error occurs
	 */
	protected synchronized void processCommands(DDMReader reader, DDMWriter writer, 
		Session session) throws Throwable
	{
		try {
			String protocolStr = reader.readCmdString(4);
			String locale = DEFAULT_LOCALE;
			String codeset = null;
			// get the version
			int version = reader.readNetworkShort();
			if (version <= 0 || version > PROTOCOL_VERSION)
				throw new Throwable(langUtil.getTextMessage("DRDA_UnknownProtocol.S",  new Integer(version).toString()));
			int localeLen = reader.readByte();
			if (localeLen > 0)
			{
				currentSession = session;
				locale = reader.readCmdString(localeLen);
				session.langUtil = new LocalizedResource(codeset,locale,DRDA_PROP_MESSAGES);
			}
			String notLocalMessage = null;
			// for now codesetLen is always 0
			int codesetLen = reader.readByte();
			int command = reader.readByte();
			if (command !=  COMMAND_TESTCONNECTION)
			{
				try {
					checkAddressIsLocal(session.clientSocket.getInetAddress());
				}catch (Exception e)
				{
					notLocalMessage = e.getMessage();
				}
			}
			if (notLocalMessage != null)
			{
				sendMessage(writer, ERROR,notLocalMessage);
				session.langUtil = null;
				currentSession = null;
				return;
			}

			switch(command)
			{
				case COMMAND_SHUTDOWN:
					sendOK(writer);
					directShutdown();
					break;
				case COMMAND_TRACE:
					sessionArg = reader.readNetworkInt();
					boolean on = (reader.readByte() == 1);
					if (setTrace(on))
					{
						sendOK(writer);
					}
					else
					{
						sendMessage(writer, ERROR,  
							localizeMessage("DRDA_SessionNotFound.U", 
							(session.langUtil == null) ? langUtil : session.langUtil,
							new String [] {new Integer(sessionArg).toString()}));
					}
					break;
				case COMMAND_TRACEDIRECTORY:
					setTraceDirectory(reader.readCmdString());
					sendOK(writer);
					consolePropertyMessage("DRDA_TraceDirectoryChange.I", traceDirectory);
					break;
				case COMMAND_TESTCONNECTION:
					databaseArg = reader.readCmdString();
					userArg = reader.readCmdString();
					passwordArg = reader.readCmdString();
					if (databaseArg != null)
						connectToDatabase(writer, databaseArg, userArg, passwordArg);
					else
						sendOK(writer);
					break;
				case COMMAND_LOGCONNECTIONS:
					boolean log = (reader.readByte() == 1);
					setLogConnections(log);
					sendOK(writer);
					consolePropertyMessage("DRDA_LogConnectionsChange.I",
						(log ? "DRDA_ON.I" : "DRDA_OFF.I"));
					break;
				case COMMAND_SYSINFO:
					sendSysInfo(writer);
					break;
				case COMMAND_PROPERTIES:
					sendPropInfo(writer);
					break;
				case COMMAND_RUNTIME_INFO:
					sendRuntimeInfo(writer);
					break;
				case COMMAND_MAXTHREADS:
					int max = reader.readNetworkInt();
					try {
						setMaxThreads(max);
					}catch (Exception e) {
						sendMessage(writer, ERROR, e.getMessage());
						return;
					}
					int newval = getMaxThreads();
					sendOKInt(writer, newval);
					consolePropertyMessage("DRDA_MaxThreadsChange.I", 
						new Integer(newval).toString());
					break;
				case COMMAND_TIMESLICE:
					int timeslice = reader.readNetworkInt();
					try {
						setTimeSlice(timeslice);
					}catch (Exception e) {
						sendMessage(writer, ERROR, e.getMessage());
						return;
					}
					newval = getTimeSlice();
					sendOKInt(writer, newval);
					consolePropertyMessage("DRDA_TimeSliceChange.I", 
						new Integer(newval).toString());
					break;
			}
		} catch (DRDAProtocolException e) {
			//we need to handle this since we aren't in DRDA land here
			consoleExceptionPrintTrace(e);

		} catch (Exception e) {
			consoleExceptionPrintTrace(e);
		}
		finally {
			session.langUtil = null;
			currentSession = null;
		}
	}
	/**
	 * Get the next session for the thread to work on
	 * Called from DRDAConnThread after session completes or timeslice
	 * exceeded.   
	 *
	 * If there is a waiting session, pick it up and put currentSession 
	 * at the back of the queue if there is one.
	 * @param currentSession	session thread is currently working on
	 *
	 * @return  next session to work on, could be same as current session
	 */
	protected Session getNextSession(Session currentSession)
	{
		Session retval = null;
		if (shutdown == true)
			return retval;
		synchronized (runQueue)
		{
			try {
				// nobody waiting - go on with current session
				if (runQueue.size() == 0)
				{
					// no current session - wait for some work
					if (currentSession == null)
					{
						while (runQueue.size() == 0)
						{
							// This thread has nothing to do now so 
							// we will add it to freeThreads
							freeThreads++;
							runQueue.wait();
							if (shutdown == true)
								return null;
							freeThreads--;
						}
					}
					else
						return currentSession;
				}
				retval = (Session) runQueue.elementAt(0);
				runQueue.removeElementAt(0);
				if (currentSession != null)
					runQueueAdd(currentSession);
			} catch (InterruptedException e) {
			// If for whatever reason (ex. database shutdown) a waiting thread is
			// interrupted while in this method, that thread is going to be
			// closed down, so we need to decrement the number of threads
			// that will be available for use.
				freeThreads--;
			}
		}
		return retval;
	}
	/**
	 * Get the stored application requester or store if we haven't seen it yet
	 *
	 * @param appRequester Application Requester to look for