ThreadWorkers.java Source code

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Here is the source code for ThreadWorkers.java

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/*
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/**
 *
 * @author dauren
 */
import com.rabbitmq.client.ConnectionFactory;
import com.rabbitmq.client.Connection;
import com.rabbitmq.client.Channel;
import com.rabbitmq.client.ConsumerCancelledException;
import com.rabbitmq.client.MessageProperties;
import com.rabbitmq.client.QueueingConsumer;
import com.rabbitmq.client.ShutdownSignalException;
import java.io.IOException;
import java.math.BigInteger;
import java.util.StringTokenizer;
import java.util.logging.Level;
import java.util.logging.Logger;

public class ThreadWorkers extends Thread {

    private static final String TASK_QUEUE_NAME = "task_queue";
    private static final String TASK_QUEUE_REPLY_NAME = "task_queue_reply";

    public void run() {
        System.out.println("MyThread running");

        ConnectionFactory factory = new ConnectionFactory();
        factory.setHost("localhost");
        Connection connection = null;
        try {
            connection = factory.newConnection();
        } catch (IOException ex) {
            Logger.getLogger(ThreadWorkers.class.getName()).log(Level.SEVERE, null, ex);
        }
        Channel channel = null;
        try {
            channel = connection.createChannel();
        } catch (IOException ex) {
            Logger.getLogger(ThreadWorkers.class.getName()).log(Level.SEVERE, null, ex);
        }

        try {
            channel.queueDeclare(TASK_QUEUE_NAME, true, false, false, null);
        } catch (IOException ex) {
            Logger.getLogger(ThreadWorkers.class.getName()).log(Level.SEVERE, null, ex);
        }
        System.out.println(" [*] Waiting for messages. To exit press CTRL+C");

        try {
            channel.basicQos(1);
        } catch (IOException ex) {
            Logger.getLogger(ThreadWorkers.class.getName()).log(Level.SEVERE, null, ex);
        }

        QueueingConsumer consumer = new QueueingConsumer(channel);
        try {
            channel.basicConsume(TASK_QUEUE_NAME, false, consumer);
        } catch (IOException ex) {
            Logger.getLogger(ThreadWorkers.class.getName()).log(Level.SEVERE, null, ex);
        }

        while (true) {
            QueueingConsumer.Delivery delivery = null;
            try {
                delivery = consumer.nextDelivery();
            } catch (InterruptedException ex) {
                Logger.getLogger(ThreadWorkers.class.getName()).log(Level.SEVERE, null, ex);
            } catch (ShutdownSignalException ex) {
                Logger.getLogger(ThreadWorkers.class.getName()).log(Level.SEVERE, null, ex);
            } catch (ConsumerCancelledException ex) {
                Logger.getLogger(ThreadWorkers.class.getName()).log(Level.SEVERE, null, ex);
            }
            String message = new String(delivery.getBody());

            System.out.println(" [x] Received '" + message + "'");
            try {

                doWork(message);
            } catch (InterruptedException ex) {
                Logger.getLogger(ThreadWorkers.class.getName()).log(Level.SEVERE, null, ex);
            } catch (IOException ex) {
                Logger.getLogger(ThreadWorkers.class.getName()).log(Level.SEVERE, null, ex);
            }
            System.out.println(" [x] Done");

            try {
                channel.basicAck(delivery.getEnvelope().getDeliveryTag(), false);
            } catch (IOException ex) {
                Logger.getLogger(ThreadWorkers.class.getName()).log(Level.SEVERE, null, ex);
            }
        }
    }

    private static String doWork(String task) throws InterruptedException, IOException {
        //for (char ch: task.toCharArray()) {
        //  if (ch == '.') Thread.sleep(1000);
        //}
        String result = "empty result";
        long threadId = Thread.currentThread().getId();
        System.out.println("in thread>>>>" + threadId);

        if (task.equalsIgnoreCase(""))
            return result;
        if (task == null)
            return result;
        //if(task.charAt(0)=='f' || task.charAt(0)=='1') return result;

        if (task.charAt(0) == 'f')
            result = "factorial of " + task.substring(1) + ">>" + factor(task.substring(1)).toString();
        else if (task.charAt(0) == 'p') {

            if (isPrime(task.substring(1).toString()))
                result = task.substring(1).toString() + " is prime";
            else
                result = task.substring(1).toString() + " is not prime";
        } else {
            result = "exponent " + task.substring(1) + ">>" + exp(task.substring(1)).toString();
        }
        // sending result
        ConnectionFactory factory = new ConnectionFactory();
        factory.setHost("localhost");
        Connection connection = factory.newConnection();
        Channel channel = connection.createChannel();
        channel.queueDeclare(TASK_QUEUE_REPLY_NAME, true, false, false, null);
        //String[] msg= {"10","second",".........."};
        //String[] msg= {"1","second","."};
        //String message ="rvr";// getMessage(msg);

        channel.basicPublish("", TASK_QUEUE_REPLY_NAME, MessageProperties.PERSISTENT_TEXT_PLAIN, result.getBytes());
        System.out.println(" [x] Sent reply to client:: '" + result + "'");

        channel.close();
        connection.close();

        return result;
    }

    private static BigInteger exp(String n) {
        StringTokenizer st = new StringTokenizer(n, "^");
        BigInteger number = new BigInteger(st.nextToken());
        BigInteger pow = new BigInteger(st.nextToken());
        BigInteger ans = BigInteger.ONE;
        BigInteger cnt = BigInteger.ONE;

        pow = pow.add(BigInteger.ONE);

        while (true) {
            ans = ans.multiply(number);
            cnt = cnt.add(BigInteger.ONE);
            if (cnt.equals(pow))
                break;
        }
        return ans;
    }

    private static boolean isPrime(String n) {
        boolean ans;
        BigInteger number = new BigInteger(n);
        if (number.isProbablePrime(100) == true) {
            ans = true;
        } else
            ans = false;
        return ans;
    }

    private static BigInteger factor(String n) {
        BigInteger ans = BigInteger.ONE;
        BigInteger cnt = BigInteger.ONE;
        BigInteger number = new BigInteger(n);
        number = number.add(BigInteger.ONE);
        while (true) {
            ans = ans.multiply(cnt);
            cnt = cnt.add(BigInteger.ONE);
            if (cnt.equals(number))
                break;
        }
        return ans;
    }

}