Scala Introduction

Reading Time: 1 minuteScala Introduction I am currently taking courses on Scala. My notes are as follows: Scala basic syntax (variables) [codesyntax lang=”scala”] val a = 2 + 5 val b: Int = 6 val s = “My string” var d = 3 [/codesyntax] Scala basic syntax (functions) [codesyntax lang=”scala”] def mult(d: Int, f: Int): Int = {

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ElasticSearch Query Samples

Reading Time: 2 minutesThis post is about sample queries for full text search. Elasticsearch query samples using NEST (.NET) and Java High Level REST Client (Java) are provided in master and java branches respectively. Note that query details are documented in ISearchService.cs  and ISearchService.java interfaces. Query Structure HTTP VERB /{index}/{type}/{id} Indexing Before implementing a full text search, we

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Dockerizing Spring Boot Application (Part 2)

Reading Time: 3 minutesReducing Docker Image Size My colleagues’ feedback about my previous post helped me investigate more efficient ways of writing Dockerfile. The first thing that I realized was choosing the right image base. Alpine based images are recommended for slimmer images and is much smaller than other base images in general. —Dockerfile 1— FROM java:8 VOLUME /tmp ADD target/demo-0.0.1-SNAPSHOT.jar

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Dockerizing Spring Boot Application

Reading Time: 3 minutesIn my previous post, I mentioned about How to run docker container on your local machine. This post is about the dockerizing backend part of the Nutrition Tracking Application. We will follow these steps: Building Spring Boot project Writing a Dockerfile Building and running docker image Step 1: Building Spring Boot project mvn clean packagewill produce a

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Docker Overview

Reading Time: 3 minutesWhat is Docker? Docker is an open platform for developing, shipping, and running applications. It is one of the popular tools to build Continuous Integration and Delivery pipelines. Each organization has its own way of building DevOps solution depending on their needs. 21 DevOps and Docker Reference Architectures pulled together the design decisions of some organizations.

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Java 8 Optionals for Null Objects

Reading Time: 2 minutesIn my previous post, I mentioned about refactoring techniques including testing interface for null checks. I have recognized that there is an alternative for it while reading Java 8 in Action: Lambdas, streams, and functional-style programming. Optional Class If there is an object that might contain a null value, we can use Optional to wrap the

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Inner Classes

Reading Time: 1 minuteHi, This post is about Inner Classes, which could be useful when you are learning Lambda Expressions and Functional Programming in Java 8. Member Inner Class They can access private variables of outer class. public class MemberInnerClass { private int outer = 5; class Inner { private int inner = 10; public void print() {

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Class Initialization

Reading Time: 2 minutesToday, I will briefly mention about the class initialization. When we execute any java program (e.g.: java InitTest), Java Virtual Machine loads and link the class, execute initializers, and invokes the main class. Initialization process has some rules. Before we go into the details, spend a few minutes to figure out the output. class SuperClass { static { System.out.print(“0

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