使用Java進行SNMP編程-SNMP4J-SNMPv1/v2-代碼實例

使用SNMP4J可以很方便的實現一個SNMP NMS的功能。
對於SNMPv1/SNMPv2，簡單的說，只需要以下幾個步驟
1) 創建Snmp對象snmp

2) 創建CommunityTarget對象target，並指定community, version, address, timeout, retry等參數。

3) 創建PDU對象pdu，並指定操作類型(GET/GETNEXT/GETBULK/SET)， 添加VariableBinding(也就是待操作的OID),
    如果是GETBULK操作，還可以指定MaxRepetitions和NonRepeaters。
 注意一定要指定MaxRepetitions，默認值是0，那樣不會返回任何結果。

4) 調用snmp.send(pdu, target)方法，發送請求請返回結果。

此外，SNMP4J提供了TableUtils類，可以很輕鬆的實現一個SNMP Walk的功能，比如一次返回一個表格下面的所有MIB值。
TableUtils類還支持指定ower bound index 和 upper bound index， 得到更小範圍的結果以提高性能。這一點對於從一個很多行的表中取一部分行的數據來說很重要。

Snmp還支持異步的send方法。

下面的代碼實例實現了GET, GETNEXT, GETBULK, Walk, SET操作，
以及一個利用異步send方法實現的agent discovery： 對一個廣播地址發送請求，等待agent返回的應答。
如果需要對一個範圍內的IP進行掃描，可以稍加改進，反覆調用異步send多次發送給不同IP。

import java.io.IOException;
import java.util.List;
import java.util.Vector;

import org.snmp4j.CommunityTarget;
import org.snmp4j.PDU;
import org.snmp4j.Snmp;
import org.snmp4j.event.ResponseEvent;
import org.snmp4j.event.ResponseListener;
import org.snmp4j.mp.SnmpConstants;
import org.snmp4j.smi.OID;
import org.snmp4j.smi.OctetString;
import org.snmp4j.smi.UdpAddress;
import org.snmp4j.smi.VariableBinding;
import org.snmp4j.transport.DefaultUdpTransportMapping;
import org.snmp4j.util.DefaultPDUFactory;
import org.snmp4j.util.TableEvent;
import org.snmp4j.util.TableUtils;

public class SNMPv2Test {
    public static void main(String[] args) throws IOException, InterruptedException {
        Snmp snmp = new Snmp(new DefaultUdpTransportMapping());
        snmp.listen();

        CommunityTarget target = new CommunityTarget();
        target.setCommunity(new OctetString("public"));
        target.setVersion(SnmpConstants.version2c);
        target.setAddress(new UdpAddress("192.168.0.100/161"));
        target.setTimeout(3000);    //3s
        target.setRetries(1);

        sendRequest(snmp, createGetPdu(), target);
        sendRequest(snmp, createGetNextPdu(), target);
        sendRequest(snmp, createGetBulkPdu(), target);
        snmpWalk(snmp, target);

        target.setCommunity(new OctetString("private"));
        sendRequest(snmp, createSetPdu(), target);

        CommunityTarget broadcastTarget = new CommunityTarget();
        broadcastTarget.setCommunity(new OctetString("public"));
        broadcastTarget.setVersion(SnmpConstants.version2c);
        broadcastTarget.setAddress(new UdpAddress("192.168.0.255/161"));
        broadcastTarget.setTimeout(5000);   //5s
        sendAsyncRequest(snmp, createGetNextPdu(), broadcastTarget);
        Thread.sleep(6000); //main thread wait 6s for the completion of asynchronous request
    }

    private static PDU createGetPdu() {
        PDU pdu = new PDU();
        pdu.setType(PDU.GET);
        pdu.add(new VariableBinding(new OID("1.3.6.1.2.1.1.3.0"))); //sysUpTime
        pdu.add(new VariableBinding(new OID("1.3.6.1.2.1.1.5.0"))); //sysName
        pdu.add(new VariableBinding(new OID("1.3.6.1.2.1.1.5")));   //expect an no_such_instance error
        return pdu;
    }

    private static PDU createGetNextPdu() {
        PDU pdu = new PDU();
        pdu.setType(PDU.GETNEXT);
        pdu.add(new VariableBinding(new OID("1.3.6.1.2.1.1.3")));   //sysUpTime
        pdu.add(new VariableBinding(new OID("1.3.6.1.2.1.1.5")));   //sysName

        return pdu;
    }

    private static PDU createGetBulkPdu() {
        PDU pdu = new PDU();
        pdu.setType(PDU.GETBULK);
        pdu.setMaxRepetitions(10);  //must set it, default is 0
        pdu.setNonRepeaters(0);
        pdu.add(new VariableBinding(new OID("1.3.6.1.2.1.1")));     //system
        return pdu;
    }

    private static PDU createSetPdu() {
        PDU pdu = new PDU();
        pdu.setType(PDU.SET);
        pdu.add(new VariableBinding(new OID("1.3.6.1.2.1.1.5.0"), new OctetString("sysname"))); //sysName
        return pdu;
    }

    private static void sendRequest(Snmp snmp, PDU pdu, CommunityTarget target)
    throws IOException {
        ResponseEvent responseEvent = snmp.send(pdu, target);
        PDU response = responseEvent.getResponse();

        if (response == null) {
            System.out.println("TimeOut...");
        } else {
            if (response.getErrorStatus() == PDU.noError) {
                Vector<? extends VariableBinding> vbs = response.getVariableBindings();
                for (VariableBinding vb : vbs) {
                    System.out.println(vb + " ," + vb.getVariable().getSyntaxString());
                }
            } else {
                System.out.println("Error:" + response.getErrorStatusText());
            }
        }
    }

    private static void sendAsyncRequest(Snmp snmp, PDU pdu, CommunityTarget target)
    throws IOException {
        snmp.send(pdu, target, null, new ResponseListener(){

            @Override
            public void onResponse(ResponseEvent event) {
                PDU response = event.getResponse();
                System.out.println("Got response from " + event.getPeerAddress());
                if (response == null) {
                    System.out.println("TimeOut...");
                } else {
                    if (response.getErrorStatus() == PDU.noError) {
                        Vector<? extends VariableBinding> vbs = response.getVariableBindings();
                        for (VariableBinding vb : vbs) {
                            System.out.println(vb + " ," + vb.getVariable().getSyntaxString());
                        }
                    } else {
                        System.out.println("Error:" + response.getErrorStatusText());
                    }
                }
            }});
    }

    private static void snmpWalk(Snmp snmp, CommunityTarget target) {
        TableUtils utils = new TableUtils(snmp, new DefaultPDUFactory(PDU.GETBULK));//GETNEXT or GETBULK
        utils.setMaxNumRowsPerPDU(5);   //only for GETBULK, set max-repetitions, default is 10
        OID[] columnOids = new OID[] {
                new OID("1.3.6.1.2.1.1.9.1.2"), //sysORID
                new OID("1.3.6.1.2.1.1.9.1.3"), //sysORDescr
                new OID("1.3.6.1.2.1.1.9.1.5")  //wrong OID, expect an null in in VariableBinding array
        };
        // If not null, all returned rows have an index in a range (lowerBoundIndex, upperBoundIndex]
        List<TableEvent> l = utils.getTable(target, columnOids, new OID("3"), new OID("10"));
        for (TableEvent e : l) {
            System.out.println(e);
        }
    }
}
引用：http://blog.csdn.net/fw0124/article/details/8559564