Skip to main content

Drools - An overview

For Java based applications the most challenging part has always been the business logic maintenance, and pick any applications which you find complex and if we ask ourself how complex it would be moving forward, the answer will always be nX times.

What do we do ? Drools comes for Rescue as a Rule Engine.

Drools provides mechanism:

a. To write business logic in simple english language
b. Easy to maintain and very simple to extend
c. Reusability of logic by defining keywords in a DSL file and using them in DSLR file.

But be careful nothing comes free, everything takes cost in terms of memory and time space.

Use Drools if you really have :

a. Business logic which you think is getting cluttered with multiple if conditions because of variety of scenarios
b. You will have growing demand of increase in the complexity
c. The business logic changes would be frequent (1 - 2 times a year would also be frequent)
d. Your server's have enough of memory as it is a memory hungary tool, it provides performance at cost of memory

Choosing a technology stack is a big decision for the lifecycle of an application, so evaluate both pros and cons and if they fits in your application requirements go for it because it is one of the easiest to use and plug in Java based Rule Engine.

Some programmers might find it cumbersome as we are used to looking at the code which is being executed and loves to debug it and understand it and see what is actually happening, latest version of Drools 5.0 address this by providing JMX support and functionality to see the generated Java Code.

Good Luck with your Rule Engine !!

Comments

Popular posts from this blog

MQTT : Android step by step guide using Eclipse Paho

For MQTT integration, recently explored Paho Android project, very simple to use, here are the steps: Intialize a client, set required options and connect.     MqttAndroidClient mqttClient = new MqttAndroidClient(BaseApplication.getAppContext(), broker, MQTT_CLIENT_ID);     //Set call back class     mqttClient.setCallback(new MqttCallbackHandler(BaseApplication.getAppContext()));     MqttConnectOptions connOpts = new MqttConnectOptions();     IMqttToken token = mqttClient.connect(connOpts); Subscribe to a topic.     token.setActionCallback(new IMqttActionListener() {       @Override       public void onSuccess(IMqttToken arg0) {            mqttClient.subscribe("TOPIC_NAME" + userId, 2, null, new IMqttActionListener() {                 @Override                 public void onSuccess(IMqttToken asyncActionToken) {                     Log.d(LOG_TAG, "Successfully subscribed to topic.");                 }                 @Override                

Listen Hindi Internet Radio Channels on PS3

PS3 is the best gadget i have ever used and its true "It only do everything". Having used it to play games, watch netflix, youtube and see my collection of pictures and listen to songs. I was searching for a way to play radio on PS3 and specifically "Hindi Internet Radio Channels" After spending couple of days, finally I have it working in few easy steps: 1. Download PS3 Media server on you laptop or PC: http://ps3mediaserver.blogspot.com/ 2. Open WEB.conf file of PS3 and add following lines: audiostream.Web,Radio=Desi Radio - www.desi-radio.com,http://76.73.90.27:80/ audiostream.Web,Radio=Desi-Radio - www.desi-radio.com,http://76.73.126.218:80/ 3. Restart PS3 Media Server 4. In your PS3, you should see PS3 Media server, open following path: Web -> Radio You should see "Desi Radio" in list. 5. Click on Desi Radio and you have live hindi songs streaming on your Ps3. I am searching more hindi internet radio channels, will update this blog when i find more