Article Categories
- All Categories
-
Data Structure
-
Networking
-
RDBMS
-
Operating System
-
Java
-
MS Excel
-
iOS
-
HTML
-
CSS
-
Android
-
Python
-
C Programming
-
C++
-
C#
-
MongoDB
-
MySQL
-
Javascript
-
PHP
-
Economics & Finance
Programming Articles
Page 1825 of 2547
Variance in Java
Java, with its robust object-oriented programming features, offers a multitude of mechanisms for programmers to develop flexible and efficient code. One such concept, often overlooked but critically important, is variance. Understanding variance is crucial for mastering Java, especially when working with generics and collections. This article provides an in-depth exploration of variance in Java, covering its types - covariance, contravariance, and invariance - and their practical applications. Understanding Variance Variance refers to how subtyping between more complex types relates to subtyping between their components. In simpler terms, it determines how the type hierarchy of classes is preserved when these classes ...
Read MoreVariables in Java Do Not Follow Polymorphism and Overriding
In the world of Object-Oriented Programming (OOP), polymorphism and overriding are key concepts that lend flexibility and dynamism to programming languages. Java, being a robust OOP language, fully supports these features. However, it's crucial to understand that these characteristics apply to methods in Java and not to variables. In this article, we will explore why variables in Java do not follow polymorphism and overriding, providing a deeper understanding of Java's variable behavior. Polymorphism in Java Polymorphism, a Greek word meaning "many forms, " is a fundamental concept of OOP. It allows objects of different types to be treated as objects ...
Read Morevar keyword in Java
Java is a statically-typed language known for its verbosity and strict type checking. However, with the release of Java 10, a new feature called Local-Variable Type Inference was introduced, bringing the var keyword to the language and changing the way Java developers code. This article will explore the var keyword, illustrating its use cases and discussing its implications for Java coding practices. Understanding 'var' in Java In Java, traditionally, we needed to explicitly declare the type of every variable we created. With the introduction of var in Java 10, this has changed. The var keyword allows you to declare ...
Read MoreValidation in Spring Boot
Data validation is a critical component of any application development. It ensures that only high-quality data that adheres to predefined standards gets processed. Spring Boot, a renowned framework in the Java ecosystem, offers robust and straightforward validation methods that developers can leverage. This article provides a comprehensive look at how validation is conducted in Spring Boot applications, enabling you to implement these essential techniques effectively. Importance of Data Validation in Spring Boot In Spring Boot, as with any application, data validation is paramount. It involves ensuring that the data received aligns with certain criteria before it's processed. Examples of validation ...
Read MoreHow to find duplicate elements in a Stream in Java
Finding duplicate elements in a stream of data is one of the common questions that is asked in Java interviews and even in the exams of many students. Java provides several ways to find duplicate elements, we will focus mainly on two ways: the first one is by using Set of Java Collection Framework and the other one is by using the built-in method of stream named Collections.frequency(). Java Program to find duplicate elements in a Stream Before discussing the different ways to get duplicate items from a collection of data, it is necessary to ...
Read MoreValid variants of main() in Java
In Java, the main() method is the entry point from where the JVM begins program execution. If you've written a Java program, you're likely familiar with the traditional main() signature: public static void main(String[] args). However, did you know that there are several valid variants of the main() method in Java? This article delves into the versatility of main() in Java, showcasing its multiple valid formats and explaining their intricacies. The Canonical Main() Method Before delving into its public static void main(String[] args) In this format, public denotes that the method can be accessed from anywhere; static ...
Read MoreUsing throw, catch and instanceof to handle Exceptions in Java
Exception handling is a fundamental aspect of Java programming that enhances the robustness of applications and promotes a seamless user experience. Key to this is understanding how to effectively use the throw, catch, and instanceof keywords to manipulate exceptions in Java. In this article, we will delve into the usage of these three mechanisms and illustrate how they collaboratively handle exceptions in Java. Understanding Exceptions in Java In Java, an exception is an event that disrupts the normal flow of a program. It's an object which is thrown by a method and caught by another method. The Java system itself ...
Read MoreHow to Find the Number of Arguments Provided at Runtime in Java?
In Java, one way of passing arguments at runtime is by using the command line or terminal. While retrieving those values of command line arguments, we may need to find the number of arguments provided by the user at runtime which is possible with the help of length property. This article aims to explain the process of passing and getting the number of arguments provided by user with the help of example programs. Getting the Number of Arguments provided by User at Runtime Before finding the number of command line arguments, our first step is ...
Read MoreUsing the super Keyword to Call a Base Class Constructor in Java
In Java's object-oriented paradigm, inheritance plays a significant role, allowing developers to create classes that reuse, extend, and modify the behavior defined in other classes. To facilitate seamless interaction between a superclass and its subclass, Java provides the super keyword. This article will focus on understanding and effectively using the super keyword in Java to call a base class constructor Exploring the Super Keyword The super keyword in Java is a reference variable that is used to refer to the immediate parent class object. Whenever you create an instance of a subclass, an instance of the parent class is also ...
Read MoreUsing Guava\'s Collectors for Collecting Streams to Immutable Collections in Java
In the world of Java programming, Google's open-source Guava library introduces powerful utilities that bolster the Java developer's toolkit. Among these, Guava's Collectors bring a unique enhancement, enabling a seamless transition of data from streams to immutable collections. This article provides a detailed guide on leveraging Guava's Collectors for collecting streams into immutable collections in Java. The Power of Immutable Collections Immutable objects have a fixed state after their creation, which means they cannot be modified. This property brings a host of benefits, including simplicity, thread-safety, and the guarantee that they will always remain in a consistent state. Java's core ...
Read More