Creating Observables and Subscribers in RxJava

RxJava is a very useful library for asynchronous and event-based programming, also called reactive programming. There are two main actors in RxJava: Observables — An object that emits a stream of data or events Observers/Subscribers — An object that acts upon the emitted data.   An observer is an object which know how to act upon 3 sort of … More Creating Observables and Subscribers in RxJava

Precision and Recall calculation for Search Engines

Search engines retrieves a number of documents as a result for a query. However, the relevance of the result can also be checked by consulting the users. For the details, see Cranfield Evaluation Methodology. Depending on the user group, different users might find different result sets more relevant. Depending on the context, sometimes, a user … More Precision and Recall calculation for Search Engines

Javascript Functions

 Are first-class objects. As a result, can be assigned to variables, can be given as arguments. Can be declared by name of by using function expression. () operator executes the function. All functions have a default property named “parameters”. It is an “array-like” object where all given parameters can be reached. Parameters are passed by … More Javascript Functions

Javascript Objects and Classes

In Javascript, there are no class declarations in JavaScript. Javascript objects are dynamic. At runtime, new properties and methods van be add and removed using “delete” operator. All Javascript properties are public. Accessing non-existing properties does not throws an exception but returns “undefined”. Properties can be used in array form, like myObject[myProperty]. Property notation is … More Javascript Objects and Classes

Reactive processing methods

Reactive programming can be achieved on several ways. Below a short list of technologies and frameworks in Java landscape. Executor service in combination of Futures. For fire and forget implementations, use Runnable threads. For implementations whereby a response is required (Fork-Join), use a Callable implementation. ExecutorCompletionService (Producer-Consumer approach). Asynchronous service calls. This can be achieved … More Reactive processing methods