Client

RandomUserGenerator.java

package playtech.client;
import java.util.Random;

public class RandomUserGenerator {

    private static final String[] userNames = {"john","jane"};
    private static final Random generator = new Random();
    private static final int RANGE = 100;

    public String getUserName()
    {
        return userNames[generator.nextInt(userNames.length)];
    }

    public String getBalanceChange()
    {
        return String.valueOf(generator.nextInt(RANGE) - generator.nextInt(RANGE));
    }
}

Start.java

package playtech.client;

import com.sun.jersey.api.client.Client;
import com.sun.jersey.api.client.ClientResponse;
import com.sun.jersey.api.client.WebResource;
import com.sun.jersey.api.client.config.ClientConfig;
import com.sun.jersey.api.client.config.DefaultClientConfig;
import playtech.service.WalletStatus;

import javax.ws.rs.core.MediaType;
import javax.ws.rs.core.UriBuilder;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.net.URI;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;


public class Start {
    private static final String BASE_URL = "http://localhost:8080/wallet/service";
    private static final String METHOD_NAME = "balance";

    public static void main(String[] args) throws IOException {
        System.out.println("Press Enter for finish");
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        while(!br.ready())
        {
        int threadsCount = 10;
        if(args.length > 1)
        {
           threadsCount = Integer.parseInt(args[0]);
        }

        List<Thread> threads = new ArrayList<Thread>();

        for (int i = 0; i < threadsCount; i++) {
            Runnable task = new WebClient(BASE_URL, METHOD_NAME);
            Thread worker = new Thread(task);
            worker.setName(String.valueOf(i));
            worker.start();
            threads.add(worker);
        }
        boolean perform= false;
        do{
            for (Thread thread : threads) {
                 perform = thread.isAlive();
            }
        } while(perform);
        System.out.println("Done. Press Enter for finish");
            try {
                Thread.sleep(5000);

            } catch (InterruptedException ie) {
                System.out.println(ie.getMessage());
            }

        }
    }


}

WebClient.java

package playtech.client;

import com.sun.jersey.api.client.ClientResponse;
import com.sun.jersey.api.client.WebResource;
import com.sun.jersey.api.client.config.ClientConfig;
import com.sun.jersey.api.client.config.DefaultClientConfig;
import playtech.service.WalletStatus;

import javax.ws.rs.core.MediaType;
import javax.ws.rs.core.UriBuilder;
import java.net.URI;

public class WebClient implements Runnable {
    private static int transaction = 0;
    private  String baseURL = "";
    private  String methodName = "";
    public WebClient(String baseURL, String method)
    {
        this.baseURL = baseURL;
        this.methodName = method;
    }
    @Override
    public  void run() {
        ClientConfig clientConfig = new DefaultClientConfig();
        //clientConfig.getClasses().add(com.sun.jersey.impl.provider.entity.JSONRootElementProvider.class);
        com.sun.jersey.api.client.Client client = com.sun.jersey.api.client.Client.create(clientConfig);
        try {
            Thread.sleep((int)Math.random() * 1000);

        } catch (InterruptedException ie) {
            System.out.println(ie.getMessage());
        }

        WebResource resource = client.resource(getBaseURI());
        RandomUserGenerator user = new RandomUserGenerator();

        ClientResponse response = resource.path(methodName).
                path(user.getUserName()).
                path(getTransactionId()).
                path(user.getBalanceChange()).
                accept(MediaType.APPLICATION_JSON)
                .post(ClientResponse.class);

        if (response.getStatus() != 200) {
            throw new RuntimeException("Failed : HTTP error code : "
                    + response.getStatus());
        }

        WalletStatus output = response.getEntity(WalletStatus.class);

        System.out.println("Output from Server .... \n");
        if (output.errorCode == 0) {
            System.out.println("Transaction: " + output.transactionId);
            System.out.println("Balance: " + output.balanceAfterChange);
        } else {
            System.out.println("Error " + output.errorCode);
        }
    }

    private  URI getBaseURI() {
        return UriBuilder.fromUri(baseURL).build();
    }

    private  String getTransactionId() {
        return String.valueOf(transaction++);
    }
}