Classes that have many optional parameters can use builder pattern to create instances of these classes.

Service provider interface (SPI) enables developers to extend applications functionalities by adding services implementation, e.g. Jar files, to classpath without modifying the application code base.

While using constructors is the default way of creating new objects, using static methods might bring more advantages according to Joshua Block's Effective Java Item-1.

Spring provides a global exception handling mechanism that can be implemented across the whole application using @ControllerAdvice annotation

JasperReports library is an open source reporting library written in Java. The library can export documents in different formats e.g. PDF, HTML, CSV...etc. This post shows a simple example of how to export PDF document using JasperReports.

Intent is a messaging object that can be used to start app components such activity within an app or to interact with other apps. Explicit intent is used to launch a specific app component while implicit intent specifies an action that can invoke other apps able to perform the action. Here we will see how to use intent to send and receive simple data between apps.

Functions in Kotlin can be stored in variables, passed as arguments to other functions and returned from other functions. However, since Kotlin is statically typed language, functions should have a type. In this post we will see how to declare the type of a function, how to use lambda to define a function and how to define a higher order function.