Showing posts with label activemq. Show all posts
Showing posts with label activemq. Show all posts

Tuesday, July 22, 2008

JMS JRuby Producer and Consumer

So , after scouring the internet trying to find 1 consolidated location that demonstrated an easy way to use JMS inside of JRuby , I finally used some internet examples and some research on the SUN JMS API website to get this working.  The biggest thing I had to figure out was how to properly structure the message from the message producer.  This is a basic setup using activemq 5.1 , jruby 1.1.2 and some basic ruby skills.  Here is what I did.

 1 - fire up out of the box activemq installation.  Literally that easy, just run bin/activemq & 
 2 - copy activemq-all-5.1.0.jar from activemq installation directory to the same directory as your JRuby scripts
 3 - create the 2 scripts below , consumer.rb and producer.rb and you are off and running.  For the Rails enthusiasts , I can imagine a very nice replacement for ActiveMessaging where you create a simple JMS library that will do an async post of messages to the queue, very nice indeed.
4 - Run each script in a separate window (jruby consumer.rb  AND jruby producer.rb).  Producer.rb will simply give you a ">" prompt to type some text to demonstrate the concept


Here is the code I ended up with:


consumer.rb
------------------------
require "java"
require "activemq-all-5.1.0.jar"

include_class "org.apache.activemq.ActiveMQConnectionFactory"
include_class "org.apache.activemq.util.ByteSequence"
include_class "org.apache.activemq.command.ActiveMQBytesMessage"
include_class "javax.jms.MessageListener"
include_class "javax.jms.Session"

class MessageHandler
include javax.jms.Session
include javax.jms.MessageListener

def onMessage(serialized_message)
message_body = serialized_message.get_content.get_data.inject("") { |body, byte| body << byte }
puts message_body
end

def run
factory = ActiveMQConnectionFactory.new("tcp://localhost:61616")
connection = factory.create_connection();
session = connection.create_session(false, Session::AUTO_ACKNOWLEDGE);
queue = session.create_queue("test1-queue");

consumer = session.create_consumer(queue);
consumer.set_message_listener(self);

connection.start();
puts "Listening..."
end
end

handler = MessageHandler.new
handler.run

producer.rb
--------------
require "java"
require "activemq-all-5.1.0.jar"
require 'readline'

include_class "org.apache.activemq.ActiveMQConnectionFactory"
include_class "org.apache.activemq.util.ByteSequence"
include_class "org.apache.activemq.command.ActiveMQBytesMessage"
include_class "javax.jms.MessageListener"
include_class "javax.jms.Session"

class MessageHandler
include javax.jms.Session
include javax.jms.MessageListener

def initialize
factory = ActiveMQConnectionFactory.new("tcp://localhost:61616")
connection = factory.create_connection();
@session = connection.create_session(false, Session::AUTO_ACKNOWLEDGE);
queue = @session.create_queue("test1-queue");

@producer = @session.create_producer(queue);
end

def send_message(line)
puts "received input of #{line}"
m = @session.createTextMessage() ;
m.set_text(line)
@producer.send(m)
end

end

handler = MessageHandler.new
loop do
line = Readline::readline('> ', true)
handler.send_message(line)
end