vhandit

Read me  if you don't know what Axon.ivy (Ivy) is. Motivation -  Ivy projects are designed to be built on a continuous integration (CI) server like Jenkins - Today, Bitbucket supports for CI with Bitbucket Pipelines - We're using Bitbucket. Then, why not? It must be very cool and convenient for us if we can centralize our CI and VCS (version control system) tools in one place. Here is an approach We have to use a maven plugin called project-build-plugin  to build ivy projects. This plugin requires an instance of Ivy engine during building time. Bitbucket Pipelines allows us to specify our own docker image as a build environment. What we need to do  is to prepare our docker image with needed stuffs such as JDK, Maven, Ivy engine, etc. Step 1. Prepare Docker images For testing purpose, I already created two docker images: Maven and Axon.ivy engine. They are now available on Docker Hub This image for Maven using Oracle JDK 8 This image for Axon.iv...

The following is a series of posts about "functional programming in Java" which is the result of my understanding by reading the book " Java 8 in Action: Lambdas, Streams, and Functional-style Programming, by Alan Mycroft and Mario Fusco ". 1. Why functional programming? 2. Functional programming in Java 8 3. Java 8 - Using Functions as Values 4. Java 8 - Persistent data structure Persistent data structure is also known as a simple technique but it's very important. Its other names are functional data structure and immutable data structure. Why is it "persistent"? Their values persist and are isolated from changes happening elsewhere. That's it! This technique is described as below: If you need a data structure to represent the result of a computation, you should make a new one and not mutable an existing data structure. Destructive updates version public static A doSomething(A a){ a.setProp1("new value"); return...

A use case I have a form which has requirements as follow: - There are some mandatory fields. - Validation is triggered when changing value on each field. - A button "Next" is enable only when all fields are entered. It turns to disabled if any field is empty. My first approach I defined a variable "isDisableNext" at a backend bean "Controller" for dynamically disabling/enabling the "Next" button by performing event "onValueChange", but, it had a problem: <h:form id="personForm"> <p:outputLabel value="First Name" for="firstName"/> <p:inputText id="firstName" value="#{person.firstName}" required="true"> <p:ajax event="change" listener="#{controller.onValueChange}" update="nextButton"/> </p:inputText> <p:outputLabel value="Last Name" for="lastName"/> <p:i...

The following is a series of posts about "functional programming in Java" which is the result of my understanding by reading the book " Java 8 in Action: Lambdas, Streams, and Functional-style Programming, by Alan Mycroft and Mario Fusco ". 1. Why functional programming? 2. Functional programming in Java 8 3. Java 8 - Using Functions as Values 4. Java 8 - Persistent data structure In general, the phrase "functional-style programming" means the behavior of functions should be like that of mathematical-style functions - no side effects. In programmers' point of views, functions may be used like other values: passed as arguments, returned as result, and stored in data structures . That means we can use the :: operator to create a method reference, and lambda expressions to directly express function values . For example: //method reference Function<String, Integer> strToInt = Integer::parseInt; //lambda expression Comparator<Integer...

In my previous post , we discussed about why we should consider to use functional programming. Now, let's delve into what functional programming in Java is. What is pure functional programming? Shortly,  f unctional programming is programming using functions. A function corresponds to a mathematical function such as log, sin. Basically, it takes zero or more arguments, give one or more result, and has no side effects. We can't completely program in pure functional style in Java Why?  For example, calling Scanner.nextLine twice typically gives different result. So, it's just called "functional-style programming". How is that? - There is no mutating structures visible to callers. That means your side effect may not be visible to a program, but it's visible to the programmer in terms of slower execution. - A function or method shouldn't throw any exceptions (follows the concept "pass arguments, return result"). We can use types like Opti...

Run Java run! ;) References [1].  http://openjdk.java.net/projects/jdk9/ [2].  https://blogs.oracle.com/theaquarium/java-ee-8-is-final-and-glassfish-50-is-released

Did you know how new features were added into Java 7? The following are functionalities that can be considered. Source: [1] Project Coin  is all about the changes in the range from syntactic sugar to new language feature. This is what we're talking about today. Since Java 7 is the first version developed in an open source manner, there is an amount of actions that must be performed for any changes as follows: Update the Java Language Specification (JSL) Implement a prototype in the source compiler Add library support essential for the change Write tests and examples Update document Etc, ... Project Coin has submitted a lot of proposals (almost 70) but only some of them are chosen to Java 7. Why? Briefly, Java is a rich static type system and it has a lot of possible interaction points between different bits of it. Making changes to this type system is prone to creating unexpected surprises. Wow! It is tough, right? Let's take a look what features Project Coi...