Object Type Casting in Java
1. Overview The Java type system is made up of two kinds of types: primitives and references. We covered primitive conversions in this article, and we’ll […]
Month: July 2021
Quick Guide to java.lang.System
1. Overview In this tutorial, we’ll take a quick look at the java.lang.System class and its features and core functionality. 2. IO System is a part of java.lang, and […]
Wrapper Classes in Java
1. Overview As the name suggests, wrapper classes are objects encapsulating primitive Java types. Each Java primitive has a corresponding wrapper: boolean, byte, short, char, int, […]
Guide to the Volatile Keyword in Java
1. Overview In the absence of necessary synchronizations, the compiler, runtime, or processors may apply all sorts of optimizations. Even though these optimizations are beneficial […]
Inheritance and Composition (Is-a vs Has-a relationship) in Java
1. Overview Inheritance and composition — along with abstraction, encapsulation, and polymorphism — are cornerstones of object-oriented programming (OOP). In this tutorial, we’ll cover the basics of inheritance […]
Using Java Assertions
1. Introduction The Java assert keyword allows developers to quickly verify certain assumptions or state of a program. In this article, we’ll take a look at how to […]
Class Loaders in Java
1. Introduction to Class Loaders Class loaders are responsible for loading Java classes during runtime dynamically to the JVM (Java Virtual Machine). Also, they are part of […]
A Guide to Java 9 Modularity
1. Overview Java 9 introduces a new level of abstraction above packages, formally known as the Java Platform Module System (JPMS), or “Modules” for short. […]
Guide to the Synchronized Keyword in Java
1. Overview This quick article will be an intro to using the synchronized block in Java. Simply put, in a multi-threaded environment, a race condition occurs when two or […]
Java – Try with Resources
1. Overview Support for try-with-resources — introduced in Java 7 — allows us to declare resources to be used in a try block with the assurance that the resources […]
Spring NoSuchBeanDefinitionException
1. Overview In this article, we are discussing the Spring org.springframework.beans.factory.NoSuchBeanDefinitionException – this is a common exception thrown by the BeanFactory when trying to resolve a bean that simply isn’t defined in […]
Circular Dependencies in Spring
1. What Is a Circular Dependency? It happens when a bean A depends on another bean B, and the bean B depends on the bean […]
Unsatisfied Dependency in Spring
1. Overview In this quick tutorial, we’ll explain Spring’s UnsatisfiedDependencyException, what causes it, and how to avoid it. 2. Cause of UnsatisfiedDependencyException UnsatisfiedDependencyException gets thrown when, as the […]
Injecting Prototype Beans into a Singleton Instance in Spring
1. Overview In this quick article, we’re going to show different approaches of injecting prototype beans into a singleton instance. We’ll discuss the use cases and […]
@Lookup Annotation in Spring
1. Introduction In this quick tutorial, we’ll take a look at Spring’s method-level dependency injection support, via the @Lookup annotation. 2. Why @Lookup? A method annotated with @Lookup tells Spring […]
How to use the Spring FactoryBean?
1. Overview There are two kinds of beans in the Spring bean container: ordinary beans and factory beans. Spring uses the former directly, whereas latter […]
Constructor Injection in Spring with Lombok
1. Introduction Lombok is an extremely useful library overcoming boilerplate code. If you are not familiar with it yet, I highly recommend taking a look […]
Spring Autowiring of Generic Types
1. Overview In this tutorial, we’ll see how to inject Spring beans by generic parameters. 2. Autowiring Generics in Spring 3.2. Spring supports injection of generic […]
Spring – Injecting Collections
1. Introduction In this tutorial, we’re going to show how to inject Java collections using the Spring framework. Simply put, we’ll demonstrate examples with the List, Map, Set collection interfaces. 2. List With @Autowired […]
Quick Guide to Spring Bean Scopes
1. Overview In this quick tutorial, we’ll learn about the different types of bean scopes in the Spring framework. The scope of a bean defines […]
