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 - Eclipse Paho integration for Android

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
                public void onFailure…

Mobile Testing

Mobile application testing falls into broadly two types:

Hardware Testing This includes testing internal hardware, screen size, resolution, space, camera, Bluetooth, WIFI etc.
Software or Application Testing This includes testing the application that are running on device. Because of types of apps this can be divided into following categories: Native appsMobile web appsHybrid apps There are some key things to be considered when testing mobile apps: Native apps have single platformNative apps are written in platforms like SDKs while Mobile web are written in html, cssNative/Hybrid apps may or may not require internet connectionMobile web apps require internet connectionNative/Hybrid apps are downloaded from playstoreMobile web apps are accessible from internet Mobile Testing complexity in comparison web applications Different range of mobile devices, screen sizes etc.Various manufactures customizationsOS types iOS, Android, Windows etc.Different versions of OS e.g. Android 4.x, 5.x, 6.x, 7.x…