Java | Sigar: Getting network traffic

Question

I'm trying to get the network traffic using the below code in Java with the help of Sigar library

import java.util.*;
import java.util.Map.Entry;

import org.hyperic.sigar.NetFlags;
import org.hyperic.sigar.NetInterfaceConfig;
import org.hyperic.sigar.NetInterfaceStat;
import org.hyperic.sigar.Sigar;
import org.hyperic.sigar.SigarException;

public class NetworkBandwidth {

    private Map<String, Long> rxCurrentMap = new HashMap<String, Long>();
    private Map<String, List<Long>> rxChangeMap = new HashMap<String, List<Long>>();
    private Map<String, Long> txCurrentMap = new HashMap<String, Long>();
    private Map<String, List<Long>> txChangeMap = new HashMap<String, List<Long>>();
    private List<String> msg;
    private Sigar sigar;
    private String TAG = "LOG: ", serverCode;
    private volatile boolean stopGettingNetworkBandwidth = false;
    private ChannelHandlerContext ctx;

    public NetworkBandwidth(String serverCode, ChannelHandlerContext ctx){
        this.sigar = new Sigar();
        this.serverCode = serverCode;
        this.ctx = ctx;
        this.msg = new ArrayList<>();
        try {
            getMetric();
            System.out.println(TAG + "NETWORK INFO: " + networkInfo());
        } catch (SigarException e) {
            System.out.println(e.toString());
        } 

    private Long[] getMetric() throws SigarException {
        for (String ni : sigar.getNetInterfaceList()) {
            // System.out.println(ni);
            NetInterfaceStat netStat = sigar.getNetInterfaceStat(ni);
            NetInterfaceConfig ifConfig = sigar.getNetInterfaceConfig(ni);
            String hwaddr = null;
            if (!NetFlags.NULL_HWADDR.equals(ifConfig.getHwaddr())) {
                hwaddr = ifConfig.getHwaddr();
            }
            if (hwaddr != null) {
                long rxCurrenttmp = netStat.getRxBytes();
                saveChange(rxCurrentMap, rxChangeMap, hwaddr, rxCurrenttmp, ni);
                long txCurrenttmp = netStat.getTxBytes();
                saveChange(txCurrentMap, txChangeMap, hwaddr, txCurrenttmp, ni);
            }
        }
        long totalrx = getMetricData(rxChangeMap);
        long totaltx = getMetricData(txChangeMap);
        for (List<Long> l : rxChangeMap.values())
            l.clear();
        for (List<Long> l : txChangeMap.values())
            l.clear();
        return new Long[] { totalrx, totaltx };
    }

    private static long getMetricData(Map<String, List<Long>> rxChangeMap) {
        long total = 0;
        for (Entry<String, List<Long>> entry : rxChangeMap.entrySet()) {
            int average = 0;
            for (Long l : entry.getValue()) {
                average += l;
            }
            total += average / entry.getValue().size();
        }
        return total;
    }

    private static void saveChange(Map<String, Long> currentMap,
                                   Map<String, List<Long>> changeMap, String hwaddr, long current,
                                   String ni) {
        Long oldCurrent = currentMap.get(ni);
        if (oldCurrent != null) {
            List<Long> list = changeMap.get(hwaddr);
            if (list == null) {
                list = new LinkedList<Long>();
                changeMap.put(hwaddr, list);
            }
            list.add((current - oldCurrent));
        }
        currentMap.put(ni, current);
    }

    private String networkInfo() throws SigarException {
        String info = sigar.getNetInfo().toString();
        info += "\n"+ sigar.getNetInterfaceConfig().toString();
        return info;
    }

    public void stopGettingNetworkBandwidth(boolean stop){
        stopGettingNetworkBandwidth = stop;
    }

    public void getBandwidth() throws SigarException, InterruptedException {
        new Thread(new Runnable() {
            @Override
            public void run() {
                while (true){
                    try{
                        Long[] m = getMetric();
                        long totalrx = m[0];
                        long totaltx = m[1];
                        System.out.print("totalrx(download): ");
                        System.out.println("\t" + Sigar.formatSize(totalrx));
                        System.out.print("totaltx(upload): ");
                        System.out.println("\t" + Sigar.formatSize(totaltx));
                        System.out.println("-----------------------------------");
                        Thread.sleep(1000);
                    }catch (SigarException e){
                        System.out.println(TAG + "Failed to get Network Bandwidth, SigarException >> " + e.toString());
                    }catch (InterruptedException e){
                        System.out.println(TAG + "Failed to get Network Bandwidth, InterruptedException >> " + e.toString());
                    }
                    if (stopGettingNetworkBandwidth)break;if (stopGettingNetworkBandwidth)break;
                }
            }
        }).start();
    }

}

I though I'm getting the network traffic when I browse into internet until I realize I'm getting unexpected result.

I'm developing Server and Client app that communicates inside the LAN, I was expecting 0 as the result of the above code when I didn't use or browse into internet but since the application was communicating inside the LAN, I'm always getting a result.

any idea on how can I get the internet usage except when the Server and Client is sending or receiving message inside the LAN ?

Answer 1

Thanks to Ron Maupin for the idea of having a condition.

Here's how I solved it

I changed the method getBandWidth() to getTraffic() ,

public void getTraffic() throws SigarException, InterruptedException {
        new Thread(new Runnable() {
            @Override
            public void run() {

                long oldReceived = 0, oldSend = 0, newReceived, newSend;

                while (true){
                    try{

                        Long[] m = getMetric();

                        newReceived = m[0];
                        newSend = m[1];

                        if(oldReceived != newReceived || oldSend != newSend){ //if the result is different from the previous

                            oldReceived = newReceived; //put the new result to old result
                            oldSend = newSend; //put the new result to old result

                            if(oldReceived > 999 || oldSend > 999 && oldReceived == 0 || oldSend == 0){
                                System.out.print("totalrx(download): ");
                                System.out.println("\t" + Sigar.formatSize(newReceived));
                                System.out.print("totaltx(upload): ");
                                System.out.println("\t" + Sigar.formatSize(newSend));
                                System.out.println("-----------------------------------");
                            }

                        }
                        Thread.sleep(1000);
                    }catch (SigarException e){
                        System.out.println(TAG + "Failed to get Network Traffic, SigarException >> " + e.toString());
                    }catch (InterruptedException e){
                        System.out.println(TAG + "Failed to get Network Traffic, InterruptedException >> " + e.toString());
                    }
                    if (stopGettingNetworkBandwidth)break;if (stopGettingNetworkBandwidth)break;
                }
            }
        }).start();
    }

I realized that I wasn't looking for the bandWidth but the network traffic, and after observing the result, I found out that when my Server and Client send and received data inside the local network, the result is less than a thousand, and when I'm browsing or downloading the result is equal to a thousand or higher.

I'm not sure if this is reliable solution but for the meantime I'm gonna used this solution until I found a second option.