Running docker containers with zeromqHow to run Dokcer with Zeromq and Java

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Running docker containers with zeromq

Hi, I am new to docker and have been trying to setup a simulation of a client server arrangement with docker and jzmq (the java port of zeromq). My code is here:

The client

import java.io.PrintWriter;
import java.io.StringWriter;
import org.zeromq.ZMQ;
import java.util.*;

public class EchoClient{
    public static void main(String[] args){
        ZMQ.Context context = ZMQ.Context(1);

        Scanner scanner = new Scanner(System.in);
        boolean close = false;
        ZMQ.Socket requester = context.socket(ZMQ.REQ);
        String serverAddr = System.getenv("SERVER_CONNECT_ADDR");
        requester.connect(serverAddr);

        try{
            while(true){
                System.out.println("Please input a line");
                String line = scanner.nextLine();
                if (line.isEmpty() || "NO".equalsIgnoreCase(line)){
                    close = true;
                }
                requeste.send(line.getBytes, 0);
                byte [] reply = requester.recv(0);
                System.out.println("Received(server response): " 
                         + new String(reply));
                if (close == true){
                    return;
                }
                System.out.println("Please input a line: ");
                line = scanner.nextLine();
                System.out.println("User input was: %s%n", line);
            }    
        } catch (IlegalStateException | NoSuchElementException e){
           System.out.println("System.in was closed; exiting");
        }

        requester.close();
        context.term();
    }
}

The server

import java.io.PrintWriter;
import java.io.StringWriter;
import org.zeromq.ZMQ;

public class EchoServer{
    public static void main(String[] args){
        ZMQ.Context context = ZMQ.Context(1);

        ZMQ.Socket responder = context.socket(ZMQ.REP);
        String ipaddress = System.getenv("SERVER_LISTEN_ADDR");
        responder.bind(ipaddress);

        try{
            while(!Thread.currentThread().isInterrupted()){
                byte[] request = responder.recv(0);
                if (request.length != 0 && 
                       "NO".equalsIgnoreCase(new String(request)){
                    System.out.println("Received (client request): " 
                        + new String(request));
                    Thread.sleep(1000);
                    String reply="Previous command: " + new String(request)
                            + "\n Next command: \n";
                } else {
                    String reply = "Server is closing";
                    responder.send(reply.getBytes(), 0);
                    Thread.currentThread().interrupt();
                }
            }
        } catch( Exception e){
            StringWriter sw = new StringWriter();
            PrintWriter pw = new PrintWriter();
            e.printStackTrace();
            System.out.println(sw.toString());
        }

        responder.close();
        context.term();
    }
}

entrypoint.sh(for Server)

#!/bin/bash
COMPLIE_ARGS=".:/usr/local/share/java/zmq.jar"
RUN_ARGS="-Djava.library.path=/usr/local/lib"
APP="EchoServer"

javac -cp ${COMPLIE_ARGS} ${APP}.java
java -cp ${COMPLIE_ARGS} ${RUN_ARGS} ${APP}

entrypoint.sh(for Client)

#!/bin/bash
COMPLIE_ARGS=".:/usr/local/share/java/zmq.jar"
RUN_ARGS="-Djava.library.path=/usr/local/lib"
APP="EchoClient"

javac -cp ${COMPLIE_ARGS} ${APP}.java
java -cp ${COMPLIE_ARGS} ${RUN_ARGS} ${APP}

docker-compose.yml

version: "2"

services: 
    serverd:
        build: serverd
        environment:
            SERVER_LISTEN_ADDR: tcp://0.0.0.0:5555

    clientd:
        build: clientd
        environment:
            SERVER_CONNECT_ADDR: tcp://serverd:5555

My OS build is Ubuntu 16.04 LTS.