simplesnmp.java

监控大型网络的软件。能够自动发现拓扑结构

/*
 * $Id: SimpleSnmp.java 4069 2007-07-06 14:00:47Z mortenv $
 *
 * Copyright 2002-2004 Norwegian University of Science and Technology
 * Copyright 2007 UNINETT AS
 * 
 * This file is part of Network Administration Visualized (NAV)
 * 
 * NAV 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.
 * 
 * NAV 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 NAV; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

package no.ntnu.nav.SimpleSnmp;

import java.io.*;
import java.util.*;
import java.net.*;

//import uk.co.westhawk.snmp.stack.*;
//import uk.co.westhawk.snmp.pdu.*;

import snmp.*;

/**
 * <p> Class for quering devices via SNMP. The aim of this class is to
 * provide a very simple API for doing basic SNMP walking.  </p>
 *
 * <p> To use first call setBaseOid(), setCs_ro() and setHost()
 * methods (or use setParams() ), then call the getAll() (or getNext()
 * ) method to retrieve values.  </p>
 *
 * @version $LastChangedRevision: 4069 $ $LastChangedDate: 2007-07-06 16:00:47 +0200 (fre, 06 jul 2007) $
 * @author Kristian Eide &lt;[e-mail]&gt;
 */

public class SimpleSnmp
{
	public static final int IFINDEX_OID = 0;
	public static final int IFINDEX_VALUE = 1;
	public static final int IFINDEX_BOTH = 2;
	public static final int IFINDEX_NONE = 3;
	public static final int IFINDEX_DEFAULT = IFINDEX_OID;

	private static final int DEFAULT_RETRIES = 4;
	private int retries = DEFAULT_RETRIES;
	private int backoff = 2;

	private String host = "127.0.0.1";
	private String cs_ro = "community";
	private String baseOid = "1.3";
	private int timeoutCnt = 0;
	private boolean gotTimeout = false;
	private long getNextDelay = 0;
	private int socketTimeout = 1000; // milliseconds
	private int snmpVersion = 0;

	private SNMPv1CommunicationInterface comInterface = null;
	private boolean valid = false;
	//private SnmpContext context = null;


	private Map cache = new HashMap();

	protected Set ignoredModules = new HashSet();

	/**
	 * Construct an empty SimpleSnmp class.
	 */
	protected SimpleSnmp() {
	}
	
	/**
	 * Construct a SimpleSnmp class and set initial parameters.
	 */
	protected SimpleSnmp(String host, String cs_ro, String baseOid) {
		setParams(host, cs_ro, baseOid);
	}

	public static SimpleSnmp simpleSnmpFactory() {
		return simpleSnmpFactory(null, null);
	}

	public static SimpleSnmp simpleSnmpFactory(String host, String cs_ro, String baseOid) {
		return simpleSnmpFactory(null, null, host, cs_ro, baseOid);
	}

	public static SimpleSnmp simpleSnmpFactory(String vendor, String type) {
		if ("hp".equals(vendor)) return new SimpleSnmpHP();
		return new SimpleSnmp();
	}

	public static SimpleSnmp simpleSnmpFactory(String vendor, String type, String host, String cs_ro, String baseOid) {
		if ("hp".equals(vendor)) return new SimpleSnmpHP(host, cs_ro, baseOid);
		return new SimpleSnmp(host, cs_ro, baseOid);
	}

	public void setHost(String host) { if (!this.host.equals(host)) valid=false; this.host = host; }
	public void setCs_ro(String cs_ro) { if (!this.cs_ro.equals(cs_ro)) valid=false; this.cs_ro = cs_ro; }
	protected String getCs_ro() { return cs_ro; }
	public void setBaseOid(String baseOid) { this.baseOid = baseOid; }
	public void setParams(String host, String cs_ro, String baseOid)
	{
		setHost(host);
		setCs_ro(cs_ro);
		setBaseOid(baseOid);
	}

	/**
	 * Set the SNMP version to use.
	 * @param version 1 = SNMPv1, 2 = SNMPv2c.
	 */	
	public void setSnmpVersion(int version) {
		if (version < 1 || version > 2) throw new RuntimeException("Invalid SNMP version: " + version);
		version--;
		if (snmpVersion != version) {
			valid = false;
			snmpVersion = version;
		}
	}

	/**
	 * Return the SNMP version used for communication by this instance.
	 * @return 1 for SNMP v1 and 2 for SNMP v2c
	 */
	public int getSnmpVersion() {
		return snmpVersion+1;
	}

	/**
	 * Set the delay, in ms, between getNext requests.
	 */
	public void setGetNextDelay(long delay)
	{
		getNextDelay = delay;
	}

	/**
	 * Set how many times the device can time out before a TimeoutException is thrown.
	 * 
	 * @deprecated Use the more aptly named {@link #setRetries(int)} method.
	 */
	public void setTimeoutLimit(int limit)
	{
		setRetries(limit);
	}

	/**
	 * Set the timeout limit to the default value (currently 4).
	 * 
	 * @deprecated Use the more aptly named {@link #setDefaultRetries()} method.
	 */
	public void setDefaultTimeoutLimit()
	{
		setDefaultRetries();
	}

	/**
	 * Set the number of times the device may time out before a TimeoutException is thrown.
	 */
	public void setRetries(int limit)
	{
		retries = Math.max(1,limit);
	}

	/**
	 * Set the number of retries to the default value, as defined by the static value DEFAULT_RETRIES
	 */
	public void setDefaultRetries()
	{
		retries = DEFAULT_RETRIES;
	}

	/**
	 * Set the UDP socket timeout for the following requests.
	 * @param socketTimeout A value in milliseconds.
	 */
	public void setSocketTimeout(int socketTimeout)
	{
		this.socketTimeout = socketTimeout;
	}

	/**
	 * Use this method to specify that only the module with the given
	 * module number should be asked for data. Note that this
	 * information is only respected if this class is subclassed; the
	 * default is to do nothing.
	 *
	 * @param module The number of the module to ask; use null to again ask all modules
	 */
	public void onlyAskModule(String module) {

	}

	/**
	 * Use this method to specify that the given module should be
	 * ignored and not collected data for. This is useful if the
	 * module is down and would only give timeout exceptions. Note
	 * that this information is only respected if this class is
	 * subclassed; the default is to do nothing.
	 *
	 * @param module The number of the module to ignore.
	 */
	public void ignoreModule(String module) {
		ignoredModules.add(module);
	}

	/**
	 * Specify if the ifindex is contained in the OID, the value,
	 * both, or there is no ifindex. This is important for certain
	 * types, e.g. HP, which need to treat the ifindex special due to
	 * unit stacking.
	 */
	public void setIfindexIs(int ifindexIs) {
		
	}

	/*
	public boolean resetGotTimeout() {
		boolean b = gotTimeout;
		gotTimeout = false;
		return b;
	}
	*/

	/**
	 * <p> Snmpwalk the given OID and return a maximum of cnt entries
	 * from the subtree.  </p>
	 *
	 * <p> Note: the baseOid prefix will be removed from any returned
	 * OIDs.  </p>
	 *
	 * @param getCnt The maximum number of OIDs to get; 0 or less means get as much as possible
	 * @param decodeHex try to decode returned hex to ASCII
	 * @return an ArrayList containing String arrays of two elements; OID and value
	 * @throws TimeoutException if the hosts times out
	 */
	public ArrayList getNext(int getCnt, boolean decodeHex) throws TimeoutException
	{
		return getAll(baseOid, getCnt, decodeHex, true, 0);
	}

	/**
	 * <p> Snmpwalk the given OID and return a maximum of cnt entries
	 * from the subtree.  </p>
	 *
	 * <p> Note: the baseOid prefix will be removed from any returned
	 * OIDs.  </p>
	 *
	 * @param getCnt The maximum number of OIDs to get; 0 or less means get as much as possible
	 * @param decodeHex try to decode returned hex to ASCII
	 * @param getNext Send GETNEXT in first packet, this will not work if you specify an exact OID
	 * @return an ArrayList containing String arrays of two elements; OID and value
	 * @throws TimeoutException if the hosts times out
	 */
	public ArrayList getNext(int getCnt, boolean decodeHex, boolean getNext) throws TimeoutException
	{
		return getAll(baseOid, getCnt, decodeHex, getNext, 0);
	}

	/**
	 * <p> Snmpwalk the given OID and return a maximum of cnt entries
	 * from the subtree.  </p>
	 *
	 * @param getCnt The maximum number of OIDs to get; 0 or less means get as much as possible
	 * @param decodeHex try to decode returned hex to ASCII
	 * @param getNext Send GETNEXT in first packet, this will not work if you specify an exact OID
	 * @param stripPrefix Strip baseOid prefix from response OIDs if true
	 * @return an ArrayList containing String arrays of two elements; OID and value
	 * @throws TimeoutException if the hosts times out
	 */
	public ArrayList getNext(int getCnt, boolean decodeHex, boolean getNext, boolean stripPrefix) throws TimeoutException
	{
		return getAll(baseOid, getCnt, decodeHex, getNext, stripPrefix, 0);
	}

	/**
	 * <p> Snmpwalk the given OID and return a maximum of cnt entries
	 * from the subtree.  </p>
	 *
	 * <p> Note: the baseOid prefix will be removed from any returned
	 * OIDs.  </p>
	 *
	 * @param baseOid Override the baseOid; if null a null value is returned
	 * @param getCnt The maximum number of OIDs to get; 0 or less means get as much as possible
	 * @param decodeHex try to decode returned hex to ASCII
	 * @param getNext Send GETNEXT in first packet, this will not work if you specify an exact OID
	 * @return an ArrayList containing String arrays of two elements; OID and value
	 * @throws TimeoutException if the hosts times out
	 */
	public ArrayList getNext(String baseOid, int getCnt, boolean decodeHex, boolean getNext) throws TimeoutException
	{
		return getAll(baseOid, getCnt, decodeHex, getNext, 0);
	}

	/**
	 * <p> Snmpwalk the given OID and return the entire subtree as a
	 * Map.  </p>
	 *
	 * <p> Note: the baseOid prefix will be removed from any returned
	 * OIDs.  </p>
	 *
	 * @param baseOid Override the baseOid; if null a null value is returned
	 * @return a Map which maps the OIDs to their corresponding values
	 * @throws TimeoutException if the hosts times out
	 */
	public Map getAllMap(String baseOid) throws TimeoutException
	{
		return getAllMap(baseOid, false, 0);
	}

	/**
	 * <p> Snmpwalk the given OID and return the entire subtree as a
	 * Map.  </p>
	 *
	 * <p> Note: the baseOid prefix will be removed from any returned
	 * OIDs.  </p>
	 *