interfaceindexesbean.java

snmp zip 包开发snmp协议

// NAME
//      $RCSfile: InterfaceIndexesBean.java,v $
// DESCRIPTION
//      [given below in javadoc format]
// DELTA
//      $Revision: 1.13 $
// CREATED
//      $Date: 2006/01/25 18:08:55 $
// COPYRIGHT
//      Westhawk Ltd
// TO DO
//

/*
 * Copyright (C) 1998 - 2006 by Westhawk Ltd
 *
 * Permission to use, copy, modify, and distribute this software
 * for any purpose and without fee is hereby granted, provided
 * that the above copyright notices appear in all copies and that
 * both the copyright notice and this permission notice appear in
 * supporting documentation.
 * This software is provided "as is" without express or implied
 * warranty.
 * author <a href="mailto:[e-mail]">Tim Panton</a>
 */

package uk.co.westhawk.snmp.beans;

import uk.co.westhawk.snmp.stack.*;
import uk.co.westhawk.snmp.pdu.*;
import java.awt.*;
import java.util.*;
import java.text.*;
import java.lang.*;
import java.io.*;
import java.beans.*;

/**
 * <p>
 * This bean collects information about the number of interfaces on a
 * system and their index.
 * </p>
 *
 * <p>
 * The number is the number of network interfaces (regardless of
 * their current state) present on this system. The number 
 * will remain the same untill the next time the SNMP server is
 * restarted. The interfaces may go up and down while running.
 * </p>
 *
 * <p>
 * The properties in the parent classes should be set, before calling
 * the action() method. Via a PropertyChangeEvent the application/applet
 * will be notified.
 * </p>
 *
 * @see SNMPBean#setHost
 * @see SNMPBean#setPort
 * @see SNMPBean#setCommunityName
 * @see SNMPRunBean#setUpdateInterval
 * @see SNMPBean#addPropertyChangeListener
 * @see SNMPBean#action
 * @see InterfaceGetNextPdu
 * 
 * @author <a href="mailto:[e-mail]">Birgit Arkesteijn</a>
 * @version $Revision: 1.13 $ $Date: 2006/01/25 18:08:55 $
 *
 */
public class InterfaceIndexesBean extends SNMPRunBean implements Observer
{
    private static final String     version_id =
        "@(#)$Id: InterfaceIndexesBean.java,v 1.13 2006/01/25 18:08:55 birgit Exp $ Copyright Westhawk Ltd";

    private InterfaceGetNextPdu pdu;
    private Hashtable interfaceHash;

    private boolean isGetNextInFlight;
    private Date lastUpdateDate = null;


/**
 * The default constructor.
 */
public InterfaceIndexesBean() 
{
    interfaceHash = new Hashtable();
}

/**
 * The constructor that will set the host and the port no.
 *
 * @param h the hostname
 * @param p the port no
 * @see SNMPBean#setHost
 * @see SNMPBean#setPort
 */
public InterfaceIndexesBean(String h, int p) 
{
    this(h, p, null);
}

/**
 * The constructor that will set the host, the port no and the local
 * bind address.
 *
 * @param h the hostname
 * @param p the port no
 * @param b the local bind address
 * @see SNMPBean#setHost
 * @see SNMPBean#setPort
 * @see SNMPBean#setBindAddress
 *
 * @since 4_14
 */
public InterfaceIndexesBean(String h, int p, String b) 
{
    this();
    setHost(h);
    setPort(p);
    setBindAddress(b);
}

/**
 * Returns the date of the moment when this bean was last updated.
 * This might be null when the first time the update was not finished.
 *
 * @return the last update date
 */
public Date getLastUpdateDate()
{
    return lastUpdateDate;
}

/**
 * Returns the indexes (as Strings) of the current interfaces (the list
 * of ifIndex).
 */
public Enumeration getInterfaceIndexes()
{
    return interfaceHash.keys();
}

/**
 * Returns the indexes (as Strings) of the current interfaces (the list
 * of ifIndex).
 *
 * @since 4_14
 */
public Set getInterfaceIndexSet()
{
    return interfaceHash.keySet();
}

/**
 * Returns the number of current interfaces.
 */
public synchronized int getInterfaceCount()
{
    return interfaceHash.size();
}

/**
 * This method starts the action of the bean. It will initialises 
 * all variables before starting.
 */
public void action()
{
    if (isHostPortReachable())
    {
        interfaceHash.clear();
        lastUpdateDate = new Date();
        isGetNextInFlight = false;
        setRunning(true);
    }
}

/**
 * Implements the running of the bean.
 *
 * It will send the Pdu, if the previous one is not still in flight.
 * @see SNMPRunBean#isRunning()
 */
public void run()
{
    while (context != null && isRunning())
    {
        if (isGetNextInFlight == false)
        {
            // start the GetNext loop again
            isGetNextInFlight = true;
            pdu = new InterfaceGetNextPdu(context);
            pdu.addObserver(this);
            pdu.addOids(null);
            try
            {
                pdu.send();
            }
            catch (PduException exc)
            {
                System.out.println("PduException " + exc.getMessage());
            }
            catch (IOException exc)
            {
                System.out.println("IOException " + exc.getMessage());
            }
        }

        try
        {
            Thread.sleep(interval);
        } 
        catch (InterruptedException ix)
        {
            ;
        }
    }
}

/**
 * This method is called when the Pdu response is received. When all
 * answers are received it will fire the property change event.
 *
 * The answers are stored in a hashtable, this is done because the speed
 * can only be calculated with the previous answer.
 *
 * @see SNMPBean#addPropertyChangeListener
 */
public void update(Observable obs, Object ov)
{
    InterfaceGetNextPdu prev;
    String hashKey;

    pdu = (InterfaceGetNextPdu) obs;
    if (pdu.getErrorStatus() == AsnObject.SNMP_ERR_NOERROR)
    {
        hashKey = String.valueOf(pdu.getIfIndex());
        if ((prev = (InterfaceGetNextPdu)interfaceHash.get(hashKey)) != null)
        {
            pdu.getSpeed(prev);
        }

        // update the hashtable with the new answer
        interfaceHash.put(hashKey, pdu);

        // perform the GetNext on the just received answer
        prev = pdu;
        pdu = new InterfaceGetNextPdu(context);
        pdu.addObserver(this);
        pdu.addOids(prev);
        try
        {
            pdu.send();
        }
        catch (PduException exc)
        {
            System.out.println("PduException " + exc.getMessage());
        }
        catch (IOException exc)
        {
            System.out.println("IOException " + exc.getMessage());
        }
    }
    else
    {
        // the GetNext loop has ended
        lastUpdateDate = new Date();
        isGetNextInFlight = false;
        firePropertyChange("InterfaceIndexes", null, null);
    }
}


}