2017-09-13 16:00
Tune up your JUnit test class template for Idea with the BDD-like syntax, Java 8 and the Mockito-AssertJ duo. Topics covered in this article may seem trivial. However, from my trainer experi… Read More
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2017-09-13 13:00
@ControllerAdvice is a annotation provided by Spring allowing you to write global code that can be applied to a wide range of controllers, varying from all controllers to a chosen package or… Read More
2017-09-13 10:00
JavaServer Pages, JavaServer Faces, and Expression Language In this article, I am going to take a look at JavaServer Pages (JSP) and Expression Language (EL) and then relate it to JavaServer… Read More
2017-09-13 04:00
Imagine you have a stream that publishes events with unpredictable frequency. Sometimes you can expect dozens of messages per second, but occasionally no events can be seen for several secon… Read More
2017-09-13 04:00
Logging—maintaining a temporal trace of operations—is vital for any mission-critical system, no matter how big or small. Same was the case with our Project-X framework, which is… Read More
2017-09-12 22:00
Gracefulness is not only an admirable human quality: it is also a must-have for any application program, especially when it is heaving the burden of mission-critical domains. UltraESB has ha… Read More
2017-09-12 19:00
In my previous article, I discussed how to maintain Resiliency in Microservice/Distributed Architecture. In this tutorial, I will discuss Distributed Service Registry. What is a Di… Read More
2017-09-12 16:00
Learn how you can speed up your analytics database applications by a factor of 1,000 by using standard Java 8 streams and Speedment’s In-JVM-Memory accelerator. Web and mobile applicat… Read More
2017-09-12 13:00
In the last post, I talked about my experience with creating RESTFul Services using Spring Boot. When creating a REST API, proper documentation is a mandatory part of it. What is Swagge… Read More
2017-09-12 10:00
The current version of HotSpot JVM includes three types of garbage collectors: – Serial Collector – Parallel Collector – The Mostly Concurrent Collectors All of them are ge… Read More
2017-09-12 05:36
Got 15 minutes? Learn how to build a functional, secure Spring Boot app complete with user login. Try Okta + OAuth 2.0 free! Create a Free Developer Account! You’ve built a microservic… Read More
2017-09-12 04:00
What is Git ? While working in a team which involves multiple developers,it is very much necessary to use a Version Control System. Version Control System is basically a Software using which… Read More
2017-09-11 22:00
Strict adherence to the rules of Scrum can lead us astray. To master scrum, we must learn to unlearn. Focusing more on the principles than the rules is what makes truly effective scrum teams… Read More
2017-09-11 19:00
Jargo is defined on its main GitHub page as “a tool to ease the handling of program arguments/options.” That page provides a Rationale for another command line processing library… Read More
2017-09-11 16:00
HATEOAS is an acronym for Hypermedia As The Engine Of Application State. Even after expanding that for you it still might not mean a lot. HATEOAS is an extra level upon REST and is used to p… Read More
2017-09-11 13:00
1. Introduction In this tutorial, we will check out how we can use Spring Security with OAuth to secure the admin resources on the server based on the path pattern (/api/**). Another path pa… Read More
2017-09-11 10:00
In the last article, I have shown you how to sort a Map in Java 8 by keys and today, I’ll teach you how to sort a Map by values using Java 8 features e.g. lambda expression… Read More
2017-09-11 07:45
Get Down to Brass Tacks with 105 Hours of Training in One of Android’s Fastest Growing Programming Languages Hey fellow geeks, This week, on our JCG Deals store, we have another extrem… Read More
2017-09-08 16:00
Everyone is talking about Microservices such as WSO2 Microservice Framework, Spring Boot, etc. Since I haven’t worked on any Spring related project since a very long time, I… Read More
2017-09-08 13:00
If you are using plain Java, since version 5 we have a handy scheduler class that allows running tasks at fixed rate or with fixed delay: import java.util.concurrent.Executors; import java.u… Read More
2017-09-08 10:00
One of my clients was trying—valiantly—to make their quarterly planning sessions work. They prepared, getting the big hotel room. They had plenty of supplies. The planning even w… Read More
2017-09-07 19:00
Earlier this week I was with a team and discussion turned to “the definition of ready.” This little idea has been growing more and more common in the last couple of years and whi… Read More
2017-09-07 16:00
The GitHub page for google-options states that google-options is a “command line argument parsing library from the folks at Google (java).” The page goes on to say, “This i… Read More
2017-09-07 13:00
In Part 1, I wrote about thinking in feature sets so everyone could see smaller chunks of work. (If you can see them, you might be able to plan for smaller and deliver smaller.) In Part 2, I… Read More
2017-09-07 10:00
1. Introduction In this tutorial, we will be understanding OAuth2 Token Authentication, such that only authenticated users and applications get a valid access token which can be subsequ… Read More
2017-09-06 13:00
The developer community seems to be in the midst of a paradigm shift, moving away from object oriented programming (OOP) principles and toward functional programming (FP) principles. We&rsqu&hell…Read More
2017-09-06 10:00
In Part 1 of this, we looked at most of the APIs in the java.nio.file.Path class. In this article, we will look at the remaining APIs. Using register() This API allows us to register an impl… Read More
2017-09-06 07:00
In Part 1, I wrote about thinking in feature sets and how to quickly create a feature set of—with any luck—smaller features. That’s because features don’t arrive at t… Read More
2017-09-05 10:00
[TL;DR: Apache Lucene 6.0 quietly introduced a powerful new feature called near-real-time (NRT) segment replication, for efficiently and reliably replicating indices from one server to anoth… Read More
2017-09-05 07:00
This post describes how to implement MQTT security. In more details, we will describe how to securing Mosquitto MQTT server. As you may already know MQTT is one of the most important pr… Read More
2017-09-05 04:00
In the previous article, we learned how to parse excessively large XML files and turn them into RxJava streams. This time let’s look at a large JSON file. We will base our ex… Read More
2017-09-04 22:00
In-memory approaches can achieve blazing speed by putting the working set of the data into the system memory. When all data is kept in memory, the need to deal with issues arising from the u… Read More
2017-09-04 19:00
In a previous blog post I had described how Spring Webflux, the reactive programming support in Spring Web Framework, uses a Kotlin based DSL to enable users to describe routes in a ver… Read More
2017-09-04 16:00
Facelets Declaration Language In part 1 I introduced the basic idea behind JavaServer Pages (JSF). In this article, I would like to introduce the Facelets declaration language. HTML tags The… Read More
2017-09-04 10:00
Generational Garbage Collectors JVM heap is divided into two different Generations. One is called Young and the second one is the Old (sometimes referred to as Tenured). The Young Generation… Read More
2017-09-04 07:45
Leap Into A New Game Development Career Through 83 Hours of Training In Industry-Standard Tools & Tech Hey fellow geeks, This week, on our JCG Deals store, we have another extreme offer… Read More
2017-09-04 07:40
Logback is provided out of the box with Spring Boot when you use one of the Spring Boot starter dependencies as they include spring-boot-starter-logging providing logging without any configu… Read More
2017-09-03 12:00
Many teams and organizations try to create one-quarter roadmaps. Here are the problems I see: Teams spend a ton of time estimating what they might do and then they select what will fit… Read More
2017-09-02 12:00
In my previous Microservice Tutorial , I have shown How We can use Hystrix as a circuit Breaker and how to give our service a breathing room to recover itself. In this tutorial, we will take… Read More
2017-09-01 19:00
Processing file as a stream turns out to be tremendously effective and convenient. Many people seem to forget that since Java 8 (3+ years!) we can very easily turn any file into a stream of… Read More
2017-09-01 16:00
This is a two-part series in which I look at JSF 2 and how it fits into the Java EE ecosystem. In part 1 I introduce the basic idea behind JavaServer Pages (JSF) and in part 2 I will introdu… Read More
2017-09-01 13:00
Groovy has the Immutable annotation which allows to create immutable classes, which is a prerequisite for creating value objects. Unfortunately, when a class has been annotated with Immutabl… Read More
2017-09-01 10:00
We (the programmers) had documentation coming out our ears. Architecture documents, design documents, user guides, functional specifications, program specifications, and much much more. Most… Read More
2017-09-01 07:00
This article is about some simple coding practice. Nothing really fancy. It is also discussed on StackOverflow. You just refactored a huge and complex loop to a more readable stream expressi… Read More
2017-08-30 04:00
What are Incubator Modules, how will they work and why should we care? Find out more ways Project Jigsaw will change how we use Java. We’ve been waiting a long time for Project Jigsaw… Read More
2017-08-29 16:00
Overview of JAX-RS Annotations (Part 3) This is a three-part series looking at the annotation that is used to implement REST endpoints. In part two of JAX-RS annotations you learnt abou… Read More
2017-08-29 10:00
The @RestController annotation in Spring MVC is nothing but a combination of the @Controller and the @ResponseBody annotation. It was added into Spring 4.0 to make the development of RESTful… Read More
2017-08-28 19:00
This IoT project explores how to integrate Arduino with Yahoo! Weather. Internet of things (IoT project) is the next big thing in the near feature. This technology is growing fast and t… Read More
2017-08-28 16:00
JArgs 1.0 has the distinction of being the subject of the 13th post of my series on parsing command line arguments in Java. JArgs is an open source (BSD license) library that has been primar… Read More
2017-08-28 13:00
The InternalResourceViewResolver is an implementation of ViewResolver in Spring MVC framework which resolves logical view name e.g. "hello" to internal physical resources e.g. Servlet and JS… Read More
2017-08-28 10:00
1. Introduction If you have not heard about Docker, then you have probably spent the last few years on some other planet of the Solar system. Docker stormed into our industry and in no time… Read More
2017-08-28 07:45
Embark On Your Coding Odyssey with A Deep Dive (58 Hours!) Into the Most Commonly Used Programming Language Hey fellow geeks, This week, on our JCG Deals store, we have another extreme offer… Read More
2017-08-28 07:13
OutOfMemoryError might be thrown when one of the following circumstances occurs: JVM run out of native memory Java heap is out of memory PermGen or Metaspace run out of memory JVM spent too… Read More
2017-08-25 16:00
Overview of JAX-RS Annotations (Part 2) This is a three-part series looking at the annotation that is used to implement REST endpoints. In part one of JAX-RS annotations you learn about… Read More
2017-08-25 10:00
Overview of JAX-RS (Part 1) The JAX-RS API forms an important part of the Java EE platforms commitment to provide standards-driven technology. The ubiquitous nature of the internet… Read More
2017-08-24 13:00
I will assume you are at least familiar with the concept of microservices — loosely coupled services that provide discrete solutions to business use cases that you can combine to solve… Read More
2017-08-24 10:00
The featured library for my twelfth post on processing command-line arguments in Java is Command-Line Arguments with Java Reflection (CLAJR). This “library” is a single Java sour… Read More
2017-08-24 07:00
If you want to consider yourself a good software developer, it doesn’t mean that you are also considered a good computer scientist, and vice versa. There is a big difference between th… Read More
2017-08-23 10:00
Safepoints There two logical groups of threads in Java application: application threads performing application logic threads performing GC When performing operations such as heap compaction… Read More
2017-08-22 10:00
Spring Security is an immensely useful technology. It allows you to secure your application without being too intrusive and allows to plug with many different authentication mechanisms. On t… Read More
2017-08-22 07:00
How to use the @Context annotation In part 4 of What is javax.ws.rs.core.context? you learned about using the @Context annotation to inject the HttpServletResponse and the Htt… Read More
2017-08-22 04:00
How can you build the ideal Java production monitoring stack? A decision maker’s guide to the tooling ecosystem Over the last couple of years we’ve had the opportunity to talk wi… Read More
2017-08-21 13:16
Discover faster, more efficient performance monitoring with an enterprise APM product learning from your apps. Take the AppDynamics APM Guided Tour! With the mobile era upon us, the way we c… Read More
2017-08-21 10:00
Every project that has a database has dilemma: how to test database-dependent code. There are several options (not mutually exclusive): Use mocks – use only unit tests and mock the dat… Read More
2017-08-21 07:01
How to use the @Context annotation In part 3 of What is javax.ws.rs.core.context? you learned how to use the @Context annotation with Request and Configuration, Providers, and Appl… Read More
2017-08-18 19:00
In this part of the series, we take a look at how we can use Spring Cloud Config with Zookeeper to manage our configuration. Introduction I’ve always found it hard to define what Zooke… Read More
2017-08-18 16:00
After the first part of the series, where we looked at a Spring Cloud Config introduction, in this post we’ll look at a concrete implementation with a Git backend and the different opt… Read More
2017-08-18 13:00
I’m a big fan of the Spring Cloud set of tools. I’ve been using them for a while both in a professional capacity (though quite limited) and a personal one. If you have not used i… Read More
2017-08-18 10:00
How to use the @Context annotation In part 2 of What is javax.ws.rs.core.context? you learned how to use the @Context annotation to retrieve security information from an injected i… Read More
2017-08-18 07:08
RxJava is missing a factory to create an infinite stream of natural numbers. Such a stream is useful e.g. when you want to assign unique sequence numbers to possibly infinite stream of event… Read More
2017-08-17 13:00
I recently received my complimentary copy of the book “Java 9 Regular Expressions” from Anubhava Srivastava published by Packt. The book is a good tutorial and introduction to an… Read More
2017-08-17 10:00
How to use the @Context annotation In part 1 of What is javax.ws.rs.core.context? you learnt how to use the @Context annotation to retrieve HTTP Header information from an injected… Read More
2017-08-17 04:00
Problem In the previous article Introduction to Spring Cloud Config Server(http://sivalabs.in/2017/08/spring-cloud-tutorials-introduction-to-spring-cloud-config-server/) we have seen ho… Read More
2017-08-16 19:00
Problem SpringBoot provides lot of flexibility in externalizing configuration properties via properties or YAML files. We can also configure properties for each environment (dev, qa, prod et… Read More
2017-08-16 16:00
The title is not a mistake. rx.Observable from RxJava 1.x is a completely different beast than io.reactivex.Observable from 2.x. Blindly upgrading rxdependency and r… Read More
2017-08-16 13:00
How to use the @Context annotation The JAX-RS API provides a very handy mechanism to inject a range of useful resources, such as HTTP Headers, into your endpoint. The @Context &hell…Read More
2017-08-16 10:00
Concourse CI 3.3.x has introduced the ability to cache paths between task runs. This feature helps speed up tasks which cache content in specific folders – here I will demons… Read More
2017-08-14 13:00
In this tutorial we will look at default and private methods within interfaces. Default methods were added in Java 8 allowing methods to be added to an interface that comes with a default im… Read More
2017-08-14 10:00
If you have been coding in Java 8 then you know that using method reference in place of lambda expression makes your code more readable, hence it is advised to replace lambda expression with… Read More
2017-08-14 07:45
Secure Your Own Network & Learn How to Become A Certified Pentester After 78 Hours Of Training Hey fellow geeks, This week, on our JCG Deals store, we have another extreme offer. We are… Read More
2017-08-11 06:22
Hate building auth? Okta makes it fast and straightforward to implement user management in your Java app. Get authentication, authorization, and user analytics working in minutes. Try the AP… Read More
2017-08-11 04:15
How does Comcast automate deployments without compromising the reliability of the X1 Platform for XFINITY TV? Automated workflows are becoming a golden standard for delivering top quality pr… Read More
2017-08-10 21:55
Until JDK 8, there was no way to create a large, thread-safe, ConcurrentHashSet in Java. The java.util.concurrent package doesn’t even have a class called ConcurrentHashSet, but from J… Read More
2017-08-10 13:00
This post describes using Ostermiller Java Utilities 1.08.02‘s CmdLn (Java Command Line Parser) to process command-line arguments from Java-based applications. The Ostermiller Java Uti… Read More
2017-08-10 10:00
When doing interviews I experience that most of the candidates do not know what private modifier in Java really means. They know something about it that is enough for every day coding, but f… Read More
2017-08-10 07:14
After I’ve expressed my concerns about the blockchain technology, let’s get a bit more practical with the blockchain. In particular, with Ethereum. I needed to send a transaction… Read More
2017-08-10 06:21
Discover faster, more efficient performance monitoring with an enterprise APM product learning from your apps. Take the AppDynamics APM Guided Tour! Enterprises have never been under more pr… Read More
2017-08-09 16:00
Rule engines, like Drools, typically make use of a custom language to define a set of rules. For example, the Drools compiler translates a drl file to an internal representation (the K… Read More
2017-08-09 13:00
Introduction MapR-DB Table Replication allows data to be replicated to another table that could be on on the same cluster or in another cluster. This is different from the automatic and intr… Read More
2017-08-09 10:00
One of the common tasks in Java project is formatting or parsing date to String and vice-versa. Parsing date means you have a String which represents a date e.g. “2017-08-3” and… Read More
2017-08-09 07:21
Introduction The last few released of Java namely Java 7, Java 8 and the upcoming Java 9 have quite a lot of features which makes the life of Java developers easier. (I know Java 9 will make… Read More
2017-08-09 04:00
If we could have the best of both worlds between C# and Java, what would that look like? The perfect programming language doesn’t exist. I hope we can agree on that, if nothing else. N… Read More
2017-08-08 19:00
As we already discovered, flatMap() does not preserve the order of original stream. Let’s illustrate this using the GeoNames API example from previous article:… Read More
2017-08-08 16:06
I’ve talked quite a bit recently about the evolution of microservices patterns and how service proxies like Envoy from Lyft can help push the responsibility of resilience, service disc… Read More
2017-08-08 13:01
The main picocli page describes picocli as “a mighty tiny command line interface” that “is a one-file Java framework for parsing command line arguments and generating polis… Read More
2017-08-08 10:00
Resource Acquisition Is Initialization (RAII) is a design idea introduced in C++ by Bjarne Stroustrup for exception-safe resource management. Thanks to garbage collection Java doesn’t… Read More
2017-08-07 07:45
Separate Yourself From the Developer Pack with 44 Intensive Hours on the Web’s Most Exciting New Framework Hey fellow geeks, This week, on our JCG Deals store, we have another extreme… Read More
2017-08-04 10:00
There are three, seamlessly similar operators in RxJava 2.x: flatMap(), concatMap() and concatMapEager(). All of them accept the same argument – a function from ori… Read More
2017-08-03 10:07
For many open source organisations, open means the same thing as transparent: open as in open book. At the Eclipse Foundation, we regard being transparent as the practice of making sure that… Read More
2017-08-03 07:07
We know that deadlines drive behavior. That’s why in scrum, and other agile methodologies, we timebox the development with those deadlines. They tell us: Focus on the important stuff… Read More
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