sesameserver.java

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/*  Sesame - Storage and Querying architecture for RDF and RDF Schema
 *  Copyright (C) 2001-2005 Aduna
 *
 *  Contact:
 *  	Aduna
 *  	Prinses Julianaplein 14 b
 *  	3817 CS Amersfoort
 *  	The Netherlands
 *  	tel. [phone]
 *  	fax. [phone]
 *
 *  	http://aduna.biz/
 *  	http://www.openrdf.org/
 *
 *  This library is free software; you can redistribute it and/or
 *  modify it under the terms of the GNU Lesser General Public
 *  License as published by the Free Software Foundation; either
 *  version 2.1 of the License, or (at your option) any later version.
 *
 *  This library 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
 *  Lesser General Public License for more details.
 *
 *  You should have received a copy of the GNU Lesser General Public
 *  License along with this library; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

package org.openrdf.sesame.server;

import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Properties;

import org.openrdf.util.io.IOUtil;
import org.openrdf.util.log.ThreadLog;

import org.openrdf.sesame.config.SystemConfig;
import org.openrdf.sesame.config.SystemConfigCenterListener;
import org.openrdf.sesame.repository.RepositoryList;
import org.openrdf.sesame.repository.local.LocalService;

/**
 * Static object that represents a locally running Sesame server.
 *
 * @author Jeen Broekstra
 * @version $Revision: 1.20 $
 */
public class SesameServer {

/*-------------+
| Variables    |
+-------------*/

	private static LocalService _localService;

	// Default: no users, no repositories
	private static SystemConfig _sysConfig = new SystemConfig();

	/** The base dir to resolve any relative paths against. **/
	private static File _baseDir = null;

	/** The version of this code base. **/
	private static String _version = null;

	/**
	 * Sails that have already been instantiated and initialized,
	 * mapped using the repository ID.
	 **/
	private static Map _sharedSails = new HashMap();

	private static List _listeners = new ArrayList();

/*-------------+
| Methods      |
+-------------*/

	/**
	 * Creates a LocalService object with the supplied SystemConfig. This
	 * LocalService can subsequently be shared across the JVM, to allow
	 * different services and protocol handlers to access the local
	 * repositories.
	 */
	public static void createLocalService() {
		_localService = new LocalService(_sysConfig);
	}

	/**
	 * Retrieves a LocalService object that can be used to access local
	 * repositories automatically
	 */
	public static LocalService getLocalService() {
		return _localService;
	}

	/**
	 * Gets the current system configuration of the system.
	 **/
	public static SystemConfig getSystemConfig() {
		return _sysConfig;
	}

	/**
	 * Sets a new system configuration for the system.
	 * Loads a new configuration and refreshes Sesame.
	 * @param newConfig the new SystemConfig
	 */
	public static void setSystemConfig(SystemConfig newConfig) {
		// Check if something changed in the RMI-related parameters
		boolean oldEnabled = false;
		String oldFac = null;
		int oldPort = -1;

		if (_sysConfig != null) {
			oldEnabled = _sysConfig.isRMIEnabled();
			oldFac = _sysConfig.getRMIFactoryClass();
			oldPort = _sysConfig.getRMIPort();
		}

		boolean newEnabled = newConfig.isRMIEnabled();
		String newFac = newConfig.getRMIFactoryClass();
		int newPort = newConfig.getRMIPort();

		if (oldEnabled != newEnabled ||
			(oldFac == null) != (newFac == null) || // one is null, the other isn't
			oldFac != null && !oldFac.equals(newFac) ||
			oldPort != newPort)
		{
			// something changed in the RMI settings

			// unbind any old RMI server
			if (oldEnabled) {
				_unbindRMIServer(oldFac, oldPort);
			}

			// bind the new RMI server
			if (newEnabled) {
				_bindRMIServer(newFac, newPort);
			}
		}

		// Unset all old system properties
		Properties oldSystemProps = _sysConfig.getSystemProps();
		Iterator keys = oldSystemProps.keySet().iterator();
		while (keys.hasNext()) {
			String key = (String)keys.next();
			System.setProperty(key, "");
		}

		// Set all new system properties
		Properties newSystemProps = newConfig.getSystemProps();
		keys = newSystemProps.keySet().iterator();
		while (keys.hasNext()) {
			String key = (String)keys.next();
			String value = newSystemProps.getProperty(key);
			System.setProperty(key, value);
		}

		_sysConfig = newConfig;

		if (_localService == null) {
			createLocalService();
		}
		else {
			_localService.setSystemConfig(newConfig);
		}

		_notifyListeners();
	}

	/**
	 * Sets the base dir against which to resolve relative paths.
	 **/
	public static void setBaseDir(File baseDir) {
		_baseDir = baseDir;
	}

	/**
	 * Gets the base dir against which to resolve relative paths (null if not set).
	 **/
	public static File getBaseDir() {
		return _baseDir;
	}

	/**
	 * Sets the default log file for all threads that have not registered
	 * themselves with ThreadLog.
	 **/
	public static void setDefaultLogFile(String fileName) {
		if (_sysConfig.getLogDir() == null || fileName == null) {
			// logDir not yet initialized or no filename, log to System.err
			ThreadLog.setDefaultLog(null, ThreadLog.WARNING);
		}
		else {
			File logDir = new File(_baseDir, _sysConfig.getLogDir());
			String logFile = new File(logDir, fileName).getPath();
			int logLevel = _sysConfig.getLogLevel();
			ThreadLog.setDefaultLog(logFile, logLevel);
		}
	}

	/**
	 * Unsets the default log file.
	 **/
	public static void unsetDefaultLogFile() {
		ThreadLog.unsetDefaultLog();
	}

	/**
	 * Sets the log file for the thread calling this method. All
	 * logging calls to ThreadLog will be logged in this file.
	 **/
	public static void setThreadLogFile(String fileName) {
		if (_sysConfig.getLogDir() == null || fileName == null) {
			// logDir not yet initialized or no filename, log to System.err
			ThreadLog.registerThread(null, ThreadLog.ALL);
		}
		else {
			File logDir = new File(_baseDir, _sysConfig.getLogDir());
			String logFile = new File(logDir, fileName).getPath();
			int logLevel = _sysConfig.getLogLevel();
			ThreadLog.registerThread(logFile, logLevel);
		}
	}

	/**
	 * Sets the log file for the thread calling this method. All
	 * logging calls to ThreadLog will be logged in this file. The
	 * calling thread is supposed to do stuff with the indicated
	 * <tt>repositoryID</tt>.
	 **/
	public static void setThreadLogFileForRepository(String repositoryID) {
		
		RepositoryList list = _localService.getRepositoryList();
		
		if (list.getRepository(repositoryID) != null) {
			// only set if the specified repository is known. if not, the thread will still log
			// in the default log file.
			setThreadLogFile("repositories/" + repositoryID + ".log");
		}
	}

	/**
	 * Unsets the log file for the thread calling this method.
	 **/
	public static void unsetThreadLogFile() {
		ThreadLog.deregisterThread();
	}

	/**
	 * Gets the version of this code base.
	 *
	 * @return A version String, e.g. "1.0".
	 **/
	public static String getVersion() {
		if (_version == null) {
			InputStream in = SesameServer.class.getClassLoader().getResourceAsStream("VERSION");

			if (in == null) {
				_version = "[VERSION FILE MISSING]";
			}
			else {
				try {
					_version = new String(IOUtil.readFully(in)).trim();
					in.close();
				}
				catch (IOException e) {
					ThreadLog.error("Unable to read version from file", e);