A Simple SNMP4J usage

For some network administrator, querying an SNMP agent is as simple as executing:

snmpwalk -v2c -c public localhost system

Similarly, Java application developer could do that as well using SNMP4J quite easily. Oh, BTW, don't complain about the length of the code because I don't know how to attach the code to this post..:( Here is the import code snippet

 org.jbs.snmputils.*
 import java.util.List;
 import org.snmp4j.mp.SnmpConstants;
 importorg.snmp4j.smi.*;

and here is how to use it somewhere in your code

    
 Address targetAddress = GenericAddress.parse("udp:localhost/161");
 String comm = "public";
 OID oid = new OID(".1.3.6.1.2.1.1");
 List result = SnmpUtils.walk(SnmpConstants.version2c,targetAddress,comm,oid);
 for (VariableBinding vb: result)
 {
          out.println(vb.getOid()+" : "+vb.getVariable().toString()+"
");
 }

Hopefully this might be useful. By the way, the code for SnmpUtils is:

package org.jbs.snmputils;

import java.util.List;
import org.snmp4j.mp.SnmpConstants;
import org.snmp4j.smi.Address;
import org.snmp4j.smi.OID;
import org.snmp4j.smi.VariableBinding;

/**
 *
 * @author masjoko
 */
public class SnmpUtils {
    public static String get(int version, Address targetaddress, String comm, OID oid)
    {
        if (version==SnmpConstants.version1)
        {
            return SnmpV1Utils.get(targetaddress, comm, oid);
        } else if (version==SnmpConstants.version2c) {
            return SnmpV2cUtils.get(targetaddress, comm, oid);
        } else {
            return null;
        }
    }
    
    public static VariableBinding getNext(int version, Address targetaddress, String comm, OID oid)
    {
        if (version==SnmpConstants.version1)
        {
            return SnmpV1Utils.getNext(targetaddress, comm, oid);
        } else if (version==SnmpConstants.version2c) {
            return SnmpV2cUtils.getNext(targetaddress, comm, oid);
        } else {
            return null;
        }
        
    }
    
    public static List walk(int version, Address address, String comm, OID rootOID)      
    {
        if (version==SnmpConstants.version1)
        {
            return SnmpV1Utils.walk(address, comm, rootOID);
        } else if (version==SnmpConstants.version2c) {
            return SnmpV2cUtils.walk(address, comm, rootOID);
        } else {
            return null;
        }        
    }
}

Which is just a wrapper that calls Snmpv2Utils.

package org.jbs.snmputils;

import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import java.util.Vector;
import java.util.logging.Level;
import java.util.logging.Logger;
import org.snmp4j.CommunityTarget;
import org.snmp4j.PDU;
import org.snmp4j.Snmp;
import org.snmp4j.TransportMapping;
import org.snmp4j.event.ResponseEvent;
import org.snmp4j.mp.SnmpConstants;
import org.snmp4j.smi.Address;
import org.snmp4j.smi.Integer32;
import org.snmp4j.smi.Null;
import org.snmp4j.smi.OID;
import org.snmp4j.smi.OctetString;
import org.snmp4j.smi.VariableBinding;
import org.snmp4j.transport.DefaultUdpTransportMapping;

public class SnmpV2cUtils {
    public static String get(Address targetaddress, String comm, OID oid)
    {
        String ret = null;        
        TransportMapping transport;
        try {
            //create transport
            transport = new DefaultUdpTransportMapping();
            CommunityTarget target = new CommunityTarget(); 
            target.setCommunity(new OctetString("public")); 
            target.setAddress(targetaddress); 
            target.setRetries(3); 
            target.setTimeout(2000); 
            target.setVersion(SnmpConstants.version2c); 

            // create the PDU 
            PDU pdu = new PDU(); 
            pdu.setType(PDU.GET);
            //put the oid you want to get
            pdu.add(new VariableBinding(oid)); 
            pdu.setNonRepeaters(0);

            //pdu string
            System.out.println("pdu " + pdu.toString()); 			 
            Snmp snmp = new Snmp(transport);
            snmp.listen();

            // send the PDU 
            ResponseEvent responseEvent = snmp.send(pdu, target); 
            Logger.getLogger(SnmpV2cUtils.class.getName()).log(Level.INFO,responseEvent.toString());            
            // extract the response PDU (could be null if timed out) 
            PDU responsePDU = responseEvent.getResponse(); 
            Logger.getLogger(SnmpV2cUtils.class.getName()).log(Level.INFO,responsePDU.toString());
            Vector vbs = responsePDU.getVariableBindings();
            if (vbs.size()>0)
            {
                VariableBinding vb = (VariableBinding) vbs.get(0);
                ret = vb.getVariable().toString();
            }

        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        return ret;
    }
    
    public static VariableBinding getNext(Address targetaddress, String comm, OID oid)
    {        
        VariableBinding ret = null;
        TransportMapping transport;
        try {
            //create transport
            transport = new DefaultUdpTransportMapping();
            CommunityTarget target = new CommunityTarget(); 
            target.setCommunity(new OctetString("public")); 
            target.setAddress(targetaddress); 
            target.setRetries(3); 
            target.setTimeout(2000); 
            target.setVersion(SnmpConstants.version2c); 

            // create the PDU 
            PDU pdu = new PDU(); 
            pdu.setType(PDU.GETNEXT);
            //put the oid you want to get
            pdu.add(new VariableBinding(oid)); 
            pdu.setNonRepeaters(0);

            //pdu string
            System.out.println("pdu " + pdu.toString()); 			 
            Snmp snmp = new Snmp(transport);
            snmp.listen();

            // send the PDU 
            ResponseEvent responseEvent = snmp.send(pdu, target); 
            Logger.getLogger(SnmpV2cUtils.class.getName()).log(Level.INFO,responseEvent.toString());            
            // extract the response PDU (could be null if timed out) 
            PDU responsePDU = responseEvent.getResponse(); 
            Logger.getLogger(SnmpV2cUtils.class.getName()).log(Level.INFO,responsePDU.toString());
            Vector vbs = responsePDU.getVariableBindings();
            if (vbs.size()>0)
            {
                ret = (VariableBinding) vbs.get(0);                
            }

        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        return ret;
    }

    public static List walk(Address address, String comm, OID rootOID)      
    {
        List ret = new ArrayList();            

        PDU requestPDU = new PDU();
        requestPDU.add(new VariableBinding(rootOID));
        requestPDU.setType(PDU.GETBULK);
        // maximum oid per pdu request
        requestPDU.setMaxRepetitions(5);

        CommunityTarget target = new CommunityTarget();
        target.setCommunity(new OctetString(comm));
        target.setAddress(address);
        target.setVersion(SnmpConstants.version2c);        

        try
        {
            TransportMapping transport = new DefaultUdpTransportMapping();
            Snmp snmp = new Snmp(transport);
            transport.listen();

            boolean finished = false;
            int iter = 0;

            while (!finished)
            {
                VariableBinding vb = null;

                ResponseEvent respEvt = snmp.send(requestPDU, target);
                Logger.getLogger(SnmpV2cUtils.class.getName()).log(Level.INFO,"GETBULK iteration number "+iter++);
                PDU responsePDU = respEvt.getResponse();
                
                if (responsePDU != null)
                {                    
                    Vector vbs = responsePDU.getVariableBindings();
                    if (vbs!=null && vbs.size()>0)
                    {
                        for (int i=0; i