基于snmp4j的简单应用

基于snmp4j，已经有很多示例；

本例子是作者原创文章，创作不易，积极鼓励；

SNMP 是专门设计用于在 IP 网络管理网络节点（服务器、工作站、路由器、交换机及HUBS等）的一种标准协议，它是一种应用层协议。

JAVA如果想使用SNMP协议，则可以通过snmp4j-2.4.3.jar实现，下面通过代码简单介绍下这个jar包的简单使用；

package com.mysnmp;

import org.snmp4j.CommunityTarget;
import org.snmp4j.PDU;
import org.snmp4j.Snmp;
import org.snmp4j.TransportMapping;
import org.snmp4j.event.ResponseEvent;
import org.snmp4j.smi.*;
import org.snmp4j.transport.DefaultUdpTransportMapping;

import java.io.IOException;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;

public class Snmp4jTool {
    public String community = "public";
    public String communityPort = "161";
    public int communityVersion = 1;
    private Snmp snmp = null;
    private Address targetAddress = null;
    private String host = null;
    private CommunityTarget target = new CommunityTarget();
    private PDU pdu = new PDU();
    private static Integer GETBULK = -91;
    private static Integer GET = -96;
    private static Integer GETNEXT = -95;

    public Snmp4jTool() {
    }

    public Snmp4jTool(String oid, String host_temp, String port_temp, String community_temp, Integer getType) {
        this.init(host_temp, port_temp, community_temp);
        this.setTarget();
        this.setPDU(oid, getType);
    }

    public static SnmpResult getOid(String oid, String host_temp, String port_temp, String community_temp) {
        Snmp4jTool tool = new Snmp4jTool(oid, host_temp, port_temp, community_temp, GET);
        return tool.processResponseSingle(oid);
    }

    private SnmpResult processResponseSingle(String oid) {
        SnmpResult res = new SnmpResult();
        ResponseEvent event = null;

        try {
            event = this.snmp.send(this.pdu, this.target);
        } catch (IOException var8) {
            var8.printStackTrace();
        }

        PDU pdu_resp = event.getResponse();
        List<VariableBinding> list = pdu_resp.getBindingList(new OID(oid));
        if (!UtilValidator.isEmpty(list)) {
            VariableBinding vb = (VariableBinding)list.get(0);
            SnmpResult sr = new SnmpResult(vb.getOid().toString(), vb.toValueString());
            return sr;
        } else {
            return res;
        }
    }

    public static List<SnmpResult> getOidSubtree(String oid, String host_temp, String port_temp, String community_temp) {
        new ArrayList();
        Snmp4jTool tool = new Snmp4jTool(oid, host_temp, port_temp, community_temp, GETNEXT);
        List<SnmpResult> list = tool.processResponse(oid);
        filterList(list);
        return list;
    }

    private static void filterList(List<SnmpResult> list) {
        for(int i = 0; i < list.size(); ++i) {
            for(int j = list.size() - 1; j > i; --j) {
                SnmpResult jo = (SnmpResult)list.get(j);
                SnmpResult io = (SnmpResult)list.get(i);
                String oidjO = jo.getOid();
                String valjO = jo.getValue();
                String oidiO = io.getOid();
                String valiO = io.getValue();
                if (!UtilValidator.isEmpty(oidjO) && !UtilValidator.isEmpty(valjO) && !UtilValidator.isEmpty(oidiO) && !UtilValidator.isEmpty(valiO) && oidjO.equals(oidiO) && valiO.equals(valjO)) {
                    list.remove(j);
                }
            }
        }

    }

    private List<SnmpResult> processResponse(String oid) {
        ArrayList res = new ArrayList();

        while(true) {
            ResponseEvent event = null;

            try {
                event = this.snmp.send(this.pdu, this.target);
            } catch (IOException var8) {
                var8.printStackTrace();
            }

            PDU pdu_resp = event.getResponse();
            if (UtilValidator.isEmpty(pdu_resp)) {
                break;
            }

            List<VariableBinding> list = pdu_resp.getBindingList(new OID(oid));
            if (UtilValidator.isEmpty(list)) {
                break;
            }

            VariableBinding vb = (VariableBinding)list.get(0);
            SnmpResult sr = new SnmpResult(vb.getOid().toString(), vb.toValueString());
            res.add(sr);
            this.pdu.set(0, vb);
        }

        return res;
    }

    private void setPDU(String oid, Integer pdu_type) {
        this.pdu.add(new VariableBinding(new OID(oid)));
        this.pdu.setType(pdu_type);
    }

    private void setTarget() {
        this.target.setCommunity(new OctetString(this.community));
        this.target.setAddress(this.targetAddress);
        this.target.setRetries(2);
        this.target.setTimeout(1500L);
        this.target.setVersion(this.communityVersion);
    }

    private void init(String host_temp, String port_temp, String community_temp) {
        this.host = host_temp;
        this.communityPort = UtilValidator.isEmpty(port_temp) ? this.communityPort : port_temp;
        this.community = UtilValidator.isEmpty(community_temp) ? this.community : community_temp;
        String udp = FormatString.append(new Object[]{"udp:", this.host, "/", this.communityPort});
        this.targetAddress = GenericAddress.parse(udp);

        try {
            TransportMapping transport = new DefaultUdpTransportMapping();
            this.snmp = new Snmp(transport);
            transport.listen();
        } catch (IOException var6) {
            var6.printStackTrace();
        } catch (Exception var7) {
            var7.printStackTrace();
        }

    }

    public static void main(String[] args) {
        List<SnmpResult> list = getOidSubtree(".1.3.6.1.2.1.2.2.1.1", "127.0.0.1", "161", "public");
        Iterator var3 = list.iterator();

        while(var3.hasNext()) {
            SnmpResult sr = (SnmpResult)var3.next();

            System.out.println(sr.getOid() + "=" + sr.getValue());
        }

    }
}

该代码实现了

public static List<SnmpResult> getOidSubtree(String oid, String host_temp, String port_temp, String community_temp) {}

该方法的主要作用是什么呢？就是给出OID，获取树下的所有列表。