Solved How do I get how many people are on another server?

Hi, Im working on a bukkit plugin for my network and I need to see if another server is online or offline and if it is online then how many people are on it, so how would I go about doing this?

 

Send a ping request to that server just like Minecraft does

 

Example of code?

 

Here is it

Code:java

import java.io.ByteArrayOutputStream;
import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.net.InetSocketAddress;
import java.net.Socket;
import java.util.List;
 
import net.minecraft.util.com.google.gson.Gson;
 
public class ServerInfo
{
    private static Gson gson = new Gson();
 
    public static int readVarInt(DataInputStream in) throws IOException
    {
        int i = 0;
        int j = 0;
        while (true)
        {
            int k = in.readByte();
            i |= (k & 0x7F) << j++ * 7;
            if (j > 5) throw new RuntimeException("VarInt too big");
            if ((k & 0x80) != 128) break;
        }
        return i;
    }
 
    public static void writeVarInt(DataOutputStream out, int paramInt) throws IOException
    {
        while (true)
        {
            if ((paramInt & 0xFFFFFF80) == 0)
            {
                out.writeByte(paramInt);
                return;
            }
 
            out.writeByte(paramInt & 0x7F | 0x80);
            paramInt >>>= 7;
        }
    }
 
    public static StatusResponse getPing(String ip, int port)
    {
        try
        {
            Socket socket = new Socket();
            OutputStream outputStream;
            DataOutputStream dataOutputStream;
            InputStream inputStream;
            InputStreamReader inputStreamReader;
 
            socket.setSoTimeout(7000);
            socket.connect(new InetSocketAddress(ip, port), 7000);
 
 
            outputStream = socket.getOutputStream();
            dataOutputStream = new DataOutputStream(outputStream);
 
            inputStream = socket.getInputStream();
            inputStreamReader = new InputStreamReader(inputStream);
 
            ByteArrayOutputStream b = new ByteArrayOutputStream();
            DataOutputStream handshake = new DataOutputStream(b);
            handshake.writeByte(0x00); //packet id for handshake
            writeVarInt(handshake, 4); //protocol version
            writeVarInt(handshake, ip.length()); //host length
            handshake.writeBytes(ip); //host string
            handshake.writeShort(port); //port
            writeVarInt(handshake, 1); //state (1 for handshake)
 
            writeVarInt(dataOutputStream, b.size()); //prepend size
            dataOutputStream.write(b.toByteArray()); //write handshake packet
 
 
            dataOutputStream.writeByte(0x01); //size is only 1
            dataOutputStream.writeByte(0x00); //packet id for ping
            DataInputStream dataInputStream = new DataInputStream(inputStream);
            int size = readVarInt(dataInputStream); //size of packet
            int id = readVarInt(dataInputStream); //packet id
 
            if (id == -1) {
                dataOutputStream.close();
                outputStream.close();
                inputStreamReader.close();
                inputStream.close();
                socket.close();
                return null;
            }
 
            if (id != 0x00) { //we want a status response
                dataOutputStream.close();
                outputStream.close();
                inputStreamReader.close();
                inputStream.close();
                socket.close();
                return null;
            }
            int length = readVarInt(dataInputStream); //length of json string
 
            if (length == -1) {
                dataOutputStream.close();
                outputStream.close();
                inputStreamReader.close();
                inputStream.close();
                socket.close();
                return null;
            }
 
            if (length == 0) {
                dataOutputStream.close();
                outputStream.close();
                inputStreamReader.close();
                inputStream.close();
                socket.close();
                return null;
            }
 
            byte[] in = new byte[length];
            dataInputStream.readFully(in);  //read json string
            String json = new String(in);
 
 
            long now = System.currentTimeMillis();
            dataOutputStream.writeByte(0x09); //size of packet
            dataOutputStream.writeByte(0x01); //0x01 for ping
            dataOutputStream.writeLong(now); //time!?
 
            readVarInt(dataInputStream);
            id = readVarInt(dataInputStream);
            if (id == -1) {
                dataOutputStream.close();
                outputStream.close();
                inputStreamReader.close();
                inputStream.close();
                socket.close();
                return null;
            }
 
            if (id != 0x01) {
                dataOutputStream.close();
                outputStream.close();
                inputStreamReader.close();
                inputStream.close();
                socket.close();
                return null;
            }
            long pingtime = dataInputStream.readLong(); //read response
 
            StatusResponse response = gson.fromJson(json, StatusResponse.class);
            response.setTime((int) (now - pingtime));
 
            dataOutputStream.close();
            outputStream.close();
            inputStreamReader.close();
            inputStream.close();
            socket.close();
 
            return response;
        }
        catch(IOException e)
        {
            return null;
        }
    }
 
    public class StatusResponse {
        private String description;
        private Players players;
        private Version version;
        private String favicon;
        private int time;
 
        public String getDescription() {
            return description;
        }
 
        public Players getPlayers() {
            return players;
        }
 
        public Version getVersion() {
            return version;
        }
 
        public String getFavicon() {
            return favicon;
        }
 
        public int getTime() {
            return time;
        }     
 
        public void setTime(int time) {
            this.time = time;
        }
 
    }
 
    public class Players {
        private int max;
        private int online;
        private List<Player> sample;
 
        public int getMax() {
            return max;
        }
 
        public int getOnline() {
            return online;
        }
 
        public List<Player> getSample() {
            return sample;
        }       
    }
 
    public class Player {
        private String name;
        private String id;
 
        public String getName() {
            return name;
        }
 
        public String getId() {
            return id;
        }
 
    }
 
    public class Version {
        private String name;
        private String protocol;
 
        public String getName() {
            return name;
        }
 
        public String getProtocol() {
            return protocol;
        }
    }
}

So you just need to to

Code:java

ServerInfo.StatusResponse sp = ServerInfo.getPing("serverip", port);

 

Thanks!!!!!!

 

xJeremyCx
Lol you basically feeded him code xD

Also ledship
Mark it as solved so that people in the future find it easily

 

xJeremyCx
This code looks good tk query a server. Mind if I use it in a plugin or 2 of mine?

 

Sorry for late reply, of course you can