jonathan alfred

i used the command java -cp . MYclass instead of java Myclass and it worked! and for the second error i got all i had to do was close the port that was opened as you told me to, and i also changed the complier to 1.8 since it kept saying i'm using a newer version of java to execute

thank you guys so much! the problem is solved now, and i'll make sure to use the code button next time! i'm just still understanding how this site works ^^

the code i'm trying to execute is:

import java.io.BufferedReader; import java.io.IOException; import java.io.InputStream; import java.io.InputStreamReader; import java.io.OutputStream; import java.io.PrintWriter; import java.net.ServerSocket; import java.net.Socket; public class ServerMT  extends Thread{ private int nclt; public static void main(String[] args){ new ServerMT().start(); } public void run() { try { ServerSocket srs=new ServerSocket(10004); System.out.println("starting server" "); while(true) { Socket s=srs.accept(); nclt++; String ip=s.getRemoteSocketAddress().toString(); new Conversation(s,ip).start(); } }catch (IOException e) { e.printStackTrace(); } } public class Conversation extends Thread { public Socket sc; public String IP; public Conversation(Socket sc,String ip) { this.sc=sc; IP=ip; } public void run() { try { System.out.println("client is connected "+IP); InputStream inps=sc.getInputStream(); InputStreamReader inpsr=new InputStreamReader(inps); BufferedReader bfr=new BufferedReader(inpsr); OutputStream outp=sc.getOutputStream(); PrintWriter pw =new PrintWriter(outp,true); pw.println("you are the client number :"+nclt); System.out.println("conversation started"); while(true) { String msg=bfr.readLine(); System.out.println(msg); int n=msg.length(); pw.println(n); }} catch(IOException e) { e.printStackTrace(); } } } }

so it does have main class and it executes and all,however i've tried using "java -cp . MYCLASS" and it seems to work now for other projects,not this one,i still get error for this one when i run 'java -cp . ServerMT" ,what i get is; java.net.BindException: Address already in use: JVM_Bind
       at java.net.DualStackPlainSocketImpl.bind0(Native Method)
       at java.net.DualStackPlainSocketImpl.socketBind(Unknown Source)
       at java.net.AbstractPlainSocketImpl.bind(Unknown Source)
       at java.net.PlainSocketImpl.bind(Unknown Source)
       at java.net.ServerSocket.bind(Unknown Source)
       at java.net.ServerSocket.<init>(Unknown Source)
       at java.net.ServerSocket.<init>(Unknown Source)
       at ServerMT.run(ServerMT.java:18)

i've deleted the classpath and it still doesn"t work , and when i run that command what i get is java version "1.8.0_271" but im not sure if thats jdk13 or 15

hello everyone, when I try to use the command "java classname" it gives me that error, but when i compile it just in Eclipse i don't get that error, the problem is with my cmd,when i go inside the source directory where my project is which is C:\Users\hp\eclipse-workspace\ServerMT\bin>, and type "dir" they list that my class is in there,but when i run the command it just doesn't work,now i somehow have two versions of java which is jdk-13.0.2 and jdk-15, both inside the programs java folder, i really don't know which one of them to use or each one of them works or if that's the source of the problem, i kept updating the environment variables  switching between ones for jdk-15 and one for jdk-13,nothing works, i really don't know how to solve this, been trying to for a week, any help will be appreciated. and when i run the command "echo %CLASSPATH%' i get C:\Program Files\Java\jdk-15\lib*.jar, but  when i type this in search on my pc i can't find the folder, i only find C:\Program Files\Java\jdk-15