SyslogdIPMgr.java

//
// This file is part of the OpenNMS(R) Application.
//
// OpenNMS(R) is Copyright (C) 2002-2003 The OpenNMS Group, Inc. All rights
// reserved.
// OpenNMS(R) is a derivative work, containing both original code, included
// code and modified
// code that was published under the GNU General Public License. Copyrights
// for modified
// and included code are below.
//
// OpenNMS(R) is a registered trademark of The OpenNMS Group, Inc.
//
// Modifications:
//
// 2003 Jan 31: Cleaned up some unused imports.
//
// Original code base Copyright (C) 1999-2001 Oculan Corp. All rights
// reserved.
//
// 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
//       
// For more information contact:
// OpenNMS Licensing <license@opennms.org>
// http://www.opennms.org/
// http://www.opennms.com/
//
// Tab Size = 8
//

package org.infosec.ismp.syslogd;

import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.HashMap;
import java.util.Map;

import javax.sql.DataSource;

final class SyslogdIPMgr {
	/**
	 * The SQL statement used to extract the list of currently known IP
	 * addresses and their node IDs from the IP Interface table.
	 */
	private final static String IP_LOAD_SQL = "SELECT ipAddr, nodeid FROM ipInterface";

	/**
	 * A Map of IP addresses and node IDs
	 */
	private static Map<String, Long> m_knownips = new HashMap<String, Long>();

	private static DataSource m_dataSource;

	/**
	 * Default construct for the instance. This constructor always throws an
	 * exception to the caller.
	 *
	 * @throws java.lang.UnsupportedOperationException
	 *                               Always thrown.
	 *                               <p/>
	 *                               Clears and synchronizes the internal known IP address cache with the
	 *                               current information contained in the database. To synchronize the cache
	 *                               the method opens a new connection to the database, loads the address,
	 *                               and then closes it's connection.
	 * @throws java.sql.SQLException Thrown if the connection cannot be created or a database
	 *                               error occurs.
	 *                               <p/>
	 *                               Clears and synchronizes the internal known IP address cache with the
	 *                               current information contained in the database. To synchronize the cache
	 *                               the method opens a new connection to the database, loads the address,
	 *                               and then closes it's connection.
	 * @throws java.sql.SQLException Thrown if the connection cannot be created or a database
	 *                               error occurs.
	 */

	public static void setDataSource(DataSource dataSource) {
		m_dataSource = dataSource;
	}

	// WTF, This is a straight Cut'n paste from TRAPD
	// private SyslodIPMgr() {
	// throw new UnsupportedOperationException("Construction is not
	// supported");
	// }
	/**
	 * Clears and synchronizes the internal known IP address cache with the
	 * current information contained in the database. To synchronize the cache
	 * the method opens a new connection to the database, loads the address,
	 * and then closes it's connection.
	 *
	 * @throws java.sql.SQLException
	 *             Thrown if the connection cannot be created or a database
	 *             error occurs.
	 */
	static synchronized void dataSourceSync() throws SQLException {
		java.sql.Connection c = null;
		try {
			// Get database connection
			c = m_dataSource.getConnection();

			// Run with it
			//
			// c.setReadOnly(true);

			Statement s = c.createStatement();
			ResultSet rs = s.executeQuery(IP_LOAD_SQL);

			if (rs != null) {
				m_knownips.clear();
				while (rs.next()) {
					String ipstr = rs.getString(1);
					long ipnodeid = rs.getLong(2);
					m_knownips.put(ipstr, ipnodeid);
				}
				rs.close();
			}

			s.close();
		} finally {
			try {
				if (c != null)
					c.close();
			} catch (SQLException sqlE) {
			}
		}
	}

	/**
	 * Returns the nodeid for the IP Address
	 *
	 * @param addr The IP Address to query.
	 * @return The node ID of the IP Address if known.
	 */
	static synchronized long getNodeId(String addr) {
		if (addr == null)
			return -1;
		return longValue(m_knownips.get(addr));
	}

	/**
	 * Sets the IP Address and Node ID in the Map.
	 *
	 * @param addr   The IP Address to add.
	 * @param nodeid The Node ID to add.
	 * @return The nodeid if it existed in the map.
	 */
	static synchronized long setNodeId(String addr, long nodeid) {
		if (addr == null || nodeid == -1)
			return -1;

		return longValue(m_knownips.put(addr, nodeid));
	}

	/**
	 * Removes an address from the node ID map.
	 *
	 * @param addr The address to remove from the node ID map.
	 * @return The nodeid that was in the map.
	 */
	static long removeNodeId(String addr) {
		if (addr == null)
			return -1;
		return longValue(m_knownips.remove(addr));
	}

	private static long longValue(Long result) {
		return (result == null ? -1 : result);
	}

} // end SyslodIPMgr