/*
* @(#)file SnmpPeer.java
* @(#)author Sun Microsystems, Inc.
* @(#)version 3.42
* @(#)date 05/08/26
*
* Copyright 2004 Sun Microsystems, Inc. All rights reserved.
* SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
*
*/
// Copyright (c) 1995-96 by Cisco Systems, Inc.
package com.sun.jmx.snmp ;
// java imports
//
import java.net.InetAddress;
import java.net.UnknownHostException;
import java.io.Serializable;
// JMX imports
//
import com.sun.jmx.snmp.SnmpPduFactory ;
// SNMP Runtime imports
//
import com.sun.jmx.snmp.SnmpPduFactoryBER ;
/**
* Holds information about an SNMP agent. This information is used to communicate with the agent.
* These are the IP address, port number, SNMP parameters, and peer channel parameters
* (such as the maximum request packet size, maximum number of variable bindings in a packet, retries, and timeouts).
* Changing these would affect all active requests.
* <P>
* The class contains the following properties:
* <UL>
* <LI><B>destPort</B>: port number of the destination host.
* <BR>The default port is <B>161</B>.
*
* <LI><B>maxVarBindLimit</B>: maximum number of OIDs which can be encoded in a single request packet.
* This is set by the user.
* <BR>A request which contains more than this limit will be automatically split into multiple requests.
* Typically used when multiplexing requests.
* <BR>The default value is 25.
*
* <LI><B>maxSnmpPacketSize</B>: maximum packet size of the request PDU.
* This can be set by the user.
* <BR> If the request crosses this limit while encoding, the request is automatically split into
* multiple small requests. Each of these requests will again be within this limit.
* <BR>The default value is (2 * 1024).
*
* <LI><B>maxTries</B>: number of times to try before giving up.
* <BR>The default number is <B>3</B>.
*
* <LI><B>timeout</B>: amount of time to wait for a response from the
* peer. If this amount of time passes without a response, and if the
* <B>maxTries</B> value has not been exceeded, the request will be
* resent. <BR>The default amount of time is <B>3000
* milliseconds</B>.
*
* <LI><B>snmpParameters</B>: SNMP parameters to be used when communicating with the agent.
* The parameters contain the protocol version and security information (the parameters can be shared amongst several peers).
*
*</UL>
* JavaBean compliant getters and setters allow the properties listed above to be modified.
*
* <p><b>This API is a Sun Microsystems internal API and is subject
* to change without notice.</b></p>
* @see com.sun.jmx.snmp.SnmpParameters
*/
public class SnmpPeer implements Serializable {
// PUBLIC VARIABLES
//-----------------
/**
* The default SNMP packet size of an SNMP request (2 * 1024).
* <BR>The maximum size is initially set to Ethernet maximum transfer unit (MTU).
*/
public static int defaultSnmpRequestPktSize = 2 * 1024 ;
/**
* The default SNMP packet size of an SNMP response (8 * 1024).
* <BR>This will be the default size that the session socket uses when receiving a packet.
*/
public static int defaultSnmpResponsePktSize = 8 * 1024 ;
// PRIVATE VARIABLES
//------------------
/**
* The maximum number of variable bindings that can be packed into a request.
* The default value is 25.
*/
private int maxVarBindLimit = 25 ;
/**
* Port number of the destination host.
* The default port is 161.
*/
private int portNum = 161 ;
/**
* Number of times to try before giving up.
* The default number is 3.
*/
private int maxTries = 3 ;
/**
* The amount of time to wait for a response from the peer.
* The default amount of time is 3000 millisec.
*/
private int timeout = 3000;
/**
* The PDU factory. The default factory is an instance of <CODE>SnmpPduFactoryBER</CODE>.
*/
private SnmpPduFactory pduFactory = new SnmpPduFactoryBER() ;
/**
* The maximum round trip time for a packet with the peer.
*/
private long _maxrtt ;
/**
* The minimum round trip time for a packet with the peer.
*/
private long _minrtt ;
/**
* The average round trip time for a packet with the peer.
*/
private long _avgrtt ;
/**
* SNMP parameters for this peer are valid for all requests using this peer.
* @see com.sun.jmx.snmp.SnmpParameters
*/
private SnmpParams _snmpParameter = new SnmpParameters() ;
/**
* Internet address of the peer to be used when communicating with the peer.
*/
private InetAddress _devAddr = null ;
/**
* Maximum packet size of the request PDU. This can be set by the user.
* If the request crosses this limit while encoding, the request is automatically split
* into multiple small request. Each of these requests will again be within this limit.
* The default value is (2 * 1024).
*/
private int maxSnmpPacketSize = defaultSnmpRequestPktSize ;
/**
* List of alternate addresses.
*/
InetAddress _devAddrList[] = null ;
/**
* The index of address currently being used.
*/
int _addrIndex = 0 ;
private boolean customPduFactory = false;
// CONSTRUCTORS
//-------------
/**
* Creates an SNMP peer object for a device. The default port is 161.
* @param host The peer name.
* @exception UnknownHostException If the host name cannot be resolved.
*/
public SnmpPeer(String host) throws UnknownHostException {
this(host, (int)161) ;
}
/**
* Creates an SNMP peer object for a device. The default port is 161.
* @param netaddr The peer <CODE>InetAddress</CODE>.
* @param port The port number.
*/
public SnmpPeer(InetAddress netaddr, int port) {
_devAddr = netaddr ;
portNum = port;
}
/**
* Creates an SNMP peer object for a device. The default port is 161.
* @param netaddr The peer <CODE>InetAddress</CODE>.
*/
public SnmpPeer(InetAddress netaddr) {
_devAddr = netaddr ;
}
/**
* Creates an SNMP peer object for a device with the specified port.
* @param host The peer name.
* @param port The port number.
* @exception UnknownHostException If the host name cannot be resolved.
*/
public SnmpPeer(String host, int port) throws UnknownHostException {
useIPAddress(host) ;
portNum = port;
}
// PUBLIC METHODS
//---------------
/**
* Sets a specific IP address to which the peer will communicate.
* Typically used to set an alternate IP address or a specific address which is known to respond to requests.
* The IP address <CODE>String</CODE> can either be a machine name, such as <CODE>ibiza</CODE>,
* or a <CODE>String</CODE> representing its IP address, such as "206.26.48.100".
* @param ipaddr Dot formatted IP address or logical host name.
* @exception UnknownHostException If the host name cannot be resolved.
*/
final public synchronized void useIPAddress(String ipaddr) throws UnknownHostException {
_devAddr = InetAddress.getByName(ipaddr) ;
}
/**
* Returns the dot-formatted IP address string (for example 171.69.220.224).
* Useful when you want to know which IP address is used
* when the address was resolved using a DNS name.
* @return The dot-formatted IP address being used.
*/
final public synchronized String ipAddressInUse() {
byte [] adr = _devAddr.getAddress() ;
return
(adr[0]&0xFF) + "." + (adr[1]&0xFF) + "." +
(adr[2]&0xFF) + "." + (adr[3]&0xFF);
}
/**
* Specifies the list of addresses to be used. When a host is not responding
* the user can switch to the next address by calling <CODE>useNextAddress</CODE>.
* @param adrList The list of <CODE>InetAddresses</CODE>.
*/
final public synchronized void useAddressList(InetAddress adrList[]) {
_devAddrList = adrList ;
_addrIndex = 0 ;
useNextAddress() ;
}
/**
* Causes all subsequent requests to go to the new address
* obtained from the specified list of alternate addresses.
* If it reaches the end of list, it starts again at the first address.
*/
final public synchronized void useNextAddress() {
if (_devAddrList == null)
return ;
/* NPCTE fix for bug 4486059, esc 0 MR 03-August-2001 */
/* if (_addrIndex > _devAddrList.length) */
if (_addrIndex > _devAddrList.length-1)
/* end of NPCTE fix for bugid 4486059 */
_addrIndex = 0 ;
_devAddr = _devAddrList[_addrIndex++] ;
}
/**
* Determines whether an SNMP <CODE>set</CODE> operation is allowed with this
* peer object. For now it just makes sure a parameter is configured for a write operation.
* @return <CODE>true</CODE> if SNMP <CODE>set</CODE> is allowed and the parameter is configured,
* <CODE>false</CODE> otherwise.
*/
public boolean allowSnmpSets() {
return _snmpParameter.allowSnmpSets() ;
}
/**
* Compares the two peer objects to determine whether they are the same. This is used
* to determine whether requests can be multiplexed.
* @param obj The object to compare <CODE>this</CODE> with.
* @return <CODE>true</CODE> if they are referring to same peer and using same address;
* <CODE>false</CODE> otherwise.
*/
public boolean equals(Object obj) {
if (this == obj)
return true ;
/*
if (obj instanceof SnmpPeer) {
SnmpPeer peer = (SnmpPeer) obj ;
if (_devAddr.equals(peer.getDestAddr()) &&
portNum == peer.getDestPort())
return true ;
}
*/
return false ;
}
/**
* Gets the list of alternate <CODE>InetAddress</CODE> configured for this peer.
* @return The <CODE>InetAddress</CODE> of the peer.
*/
final public InetAddress[] getDestAddrList() {
return _devAddrList;
}
/**
* Gets the <CODE>InetAddress</CODE> object for this peer.
* @return The <CODE>InetAddress</CODE> of the peer.
*/
final public InetAddress getDestAddr() {
return _devAddr ;
}
/**
* Gets the destination port number of the peer to which SNMP requests are to be sent.
* @return The destination port number.
*/
final public int getDestPort() {
return portNum ;
}
/**
* Changes the port address of the destination for the request.
* @param newPort The destination port.
*/
final public synchronized void setDestPort(int newPort) {
portNum = newPort ;
}
/**
* Gets the timeout to wait for a response from the peer.
* @return The value of the timeout property.
*/
final public int getTimeout() {
return timeout;
}
/**
* Changes the timeout to wait for a response from the peer.
* @param newTimeout The timeout (in milliseconds).
*/
final public synchronized void setTimeout(int newTimeout) {
if (newTimeout < 0)
throw new IllegalArgumentException();
timeout= newTimeout;
}
/**
* Gets the number of times to try before giving up.
* @return The maximun number of tries.
*/
final public int getMaxTries() {
return maxTries;
}
/**
* Changes the maximun number of times to try before giving up.
* @param newMaxTries The maximun number of tries.
*/
final public synchronized void setMaxTries(int newMaxTries) {
if (newMaxTries < 0)
throw new IllegalArgumentException();
maxTries= newMaxTries;
}
/**
* Gets the name specified in the constructor while creating this object.
* @return The name of the host as specified while creating this object.
*/
final public String getDevName() {
return getDestAddr().getHostName() ;
}
/**
* Returns the <CODE>String</CODE> representation for this <CODE>SnmpPeer</CODE>.
* @return The <CODE>String</CODE> representation.
*/
public String toString() {
return "Peer/Port : " + getDevName() + "/" + getDestPort() ;
}
/**
* Gets the maximum number of variable bindings that can be sent to a peer.
* @return The maximum variable bindings that can be encoded into a request packet.
*/
final public synchronized int getVarBindLimit() {
return maxVarBindLimit ;
}
/**
* Configures the maximum number of variable bindings that can be sent to a peer.
* @param limit The desired limit.
*/
final public synchronized void setVarBindLimit(int limit) {
maxVarBindLimit = limit ;
}
/**
* Sets the <CODE>SnmpParams</CODE> object associated with the peer.
* @param params The desired parameters.
*/
public void setParams(SnmpParams params) {
_snmpParameter = params;
}
/**
* Gets the <CODE>SnmpParams</CODE> object associated with the peer.
* @return The associated parameters.
*/
public SnmpParams getParams() {
return _snmpParameter;
}
/**
* Gets the maximum request packet size that is currently used.
* @return The maximum request packet size.
*/
final public int getMaxSnmpPktSize() {
return maxSnmpPacketSize ;
}
/**
* Configures the maximum packet size that can be used when generating an SNMP request.
* @param newsize The desired packet size.
*/
final public synchronized void setMaxSnmpPktSize(int newsize) {
maxSnmpPacketSize = newsize ;
}
boolean isCustomPduFactory() {
return customPduFactory;
}
/**
* Finalizer of the <CODE>SnmpPeer</CODE> objects.
* This method is called by the garbage collector on an object
* when garbage collection determines that there are no more references to the object.
* <P>Sets all the references to this SNMP peer object to <CODE>null</CODE>.
*/
public void finalize() {
_devAddr = null ;
_devAddrList = null ;
_snmpParameter = null ;
}
/**
* Gets the minimum round trip time for a packet with the peer.
* @return The minimum round trip time for a packet with the peer.
*/
public long getMinRtt() {
return _minrtt ;
}
/**
* Gets the maximum round trip time for a packet with the peer.
* @return The maximum round trip time for a packet with the peer.
*/
public long getMaxRtt() {
return _maxrtt ;
}
/**
* Gets the average round trip time for a packet with the peer.
* @return The average round trip time for a packet with the peer.
*/
public long getAvgRtt() {
return _avgrtt ;
}
// PRIVATE METHODS
//----------------
private void updateRttStats(long tm) {
if (_minrtt > tm)
_minrtt = tm ;
else if (_maxrtt < tm)
_maxrtt = tm ;
else
_avgrtt = tm ; // to do later.
}
}
|
