Below you'll find a list of all posts that have been tagged as “Java”
1. Introduction In this article, we’ll discuss a number of approaches that can be helpful for improving the performance of a Java application. We’ll start with how to define measurable performance goals and then look at different tools to measure, monitor application performance and identify bottlenecks. We’ll also look at some of the common Java code level optimizations as well …
The word polymorphism is used in various contexts and describes situations in which something occurs in several different forms. In computer science, it describes the concept that objects of different types can be accessed through the same interface. Each type can provide its own, independent implementation of this interface. It is one of the core concepts of object-oriented programming (OOP). …
Inheritance is one of the core concepts of object-oriented programming (OOP) languages. It is a mechanism where you can to derive a class from another class for a hierarchy of classes that share a set of attributes and methods. You can use it to declare different kinds of exceptions, add custom logic to existing frameworks, and even map your domain …
Introduction to Debugging Troubleshooting a problem on a remote server, especially in production, is not an easy task. Sometimes it involves debugging the application code directly on the server. But the production servers are usually run in a strict environment, where not all convenient developer tools are available. In this article, you’ll discover how to configure a running web server …
Despite being over 20 years old, Java is still one of the most widely-used programming languages. Just look at the stats: according to the 2017 Stack Overflow Developer Survey, Java is the third most popular technology in the world. The TIOBE index, which is a ranking based on the number of skilled engineers worldwide, courses, and third-party vendors, shows an …
Encapsulation is one of the fundamental concepts in object-oriented programming (OOP). It describes the idea of bundling data and methods that work on that data within one unit, e.g., a class in Java. This concept is also often used to hide the internal representation, or state, of an object from the outside. This is called information hiding. The general idea …
Abstraction is one of the key concepts of object-oriented programming (OOP) languages. Its main goal is to handle complexity by hiding unnecessary details from the user. That enables the user to implement more complex logic on top of the provided abstraction without understanding or even thinking about all the hidden complexity. That’s a very generic concept that’s not limited to …
Introduction to Spring Security In this article, you’ll learn how to quickly and easily configure and set up a Spring Security based web application using the Java configuration. Security is, not surprisingly, an evergrowing concern and certainly a core focus of any developer working on applications today. Project Setup The fastest way to get on track with Spring Security is …
We already talked a lot about exception handling on this blog and described the differences between checked and unchecked exceptions, best practices and common mistakes. If you’ve read these posts, you probably recognized a pattern. You should provide detailed information about the situation that caused the exception, and you should not remove anything that might be useful to the caller. …
Introduction This is an in-depth look at the powerful features and internal workings of Spring Web MVC, which is a part of the Spring Framework. The source code for this article is available over on GitHub. Project Setup Throughout this article, we’ll use the latest and greatest Spring Framework 5. We’re focusing here on the Spring’s classic web stack, which …
Most developers expect that performance optimization is a complicated topic that requires a lot of experience and knowledge. Okay, that’s not entirely wrong. Optimizing an application to get the best performance possible isn’t an easy task. But that doesn’t mean that you can’t do anything if you haven’t acquired that knowledge. There are several easy to follow recommendations and best …
Overview of Java application metrics Monitoring a running application is crucial for visibility and making sure the system is functioning as expected, as well as to identify any potential issues, tweak and optimize the running conditions, and resolve any errors that may occur. This is where Application Performance Monitoring (APM) tools can make your life a whole lot easier by …
Overview of JVM Metrics In this article, we’ll cover how you can monitor an application that runs on the Java Virtual Machine by going over some of the critical metrics you need to track. And, as a monitoring tool, we’ll use Stackify Retrace, a full APM solution. The application we’ll monitor to exemplify these metrics is a real-world Java web …
Today we’ll be talking about microservices in Java. While it’s true that Java EE has a robust platform for writing, deploying, and managing enterprise-level microservices, in this article I will create a RESTful microservice that is as slim as possible. Don’t worry – we won’t be reinventing the wheel by marshaling our own data or anything. We’ll be using JBoss’ …
1. Introduction In this article, we’ll have a look at a core Java technology – Java Management Extension (JMX). We’ll start with a quick intro to exactly what JMX is, and we’ll quickly move to some interesting things you can do with the technology. 2. What Is Java Management Extension Technology Introduced all the way back in Java 2, JMX …
The world of information technology is an ever-changing landscape. Simply thinking back to the infrastructure and functions of a webpage 5, 10, 15 years ago can make any programmer cringe. Staying current on industry strategies and best practices is essential for developers of all levels. Blogs can provide great insight and perspective from industry peers and colleagues. All over the …
In the real world, a lot of mission-critical business logic lives in background services. Buying something from an e-commerce website, like Amazon, kicks off a wide array of tasks that must be completed after you click to confirm your order. Monitoring the performance of your web applications is only part of the puzzle if you want to proactively ensure your …
Overview Monitoring the metrics and runtime characteristics of an application server is essential to ensure the adequate functioning of the applications running on that server, as well as to prevent or resolve potential issues in a timely manner. As far as Java applications go, one of the most commonly used servers is Apache Tomcat, which will be the focus of …
Java Language and Terminology In this article, we’ll explore the foundations and core concepts of the Java language and terminology. The write-up is divided into sections, ordered alphabetically to enable fast and easy search for these definitions. A abstract – a keyword used in a class or method definition, which specifies that the method/class is not going to be instantiated, …
Introduction to JShell The shell or the REPL is a well-known tool in many programming languages. Typically, this is more common in scripting languages such as Python or Node, but more recently it’s been adopted by JVM languages like Clojure and Groovy as well. The upcoming Java 9 release finally brings this shell functionality to the Java language as well, in the form …
