Factory Method Pattern for Spring Hateoas Links

Problem Description You have a single class in your application where you create Hateoas Links for different API versions (e.g.: V1 and V2). The class grows quickly with time as you add a lot of logic for those versions. You want to refactor the existing class so that it is easier to be modified for […]

How to read and override Spring Boot YAML Properties

There are some cases where we need to read and override YAML properties for implementation and testing purposes. This short tutorial will teach you how to do it. You can find the source code on GitHub. Project Structure The project structure is as follows. Reading a YAML Property There are some cases that we read […]

Testing HTTP Methods using Mockito framework

In this post, you will learn how to create HTTP methods in Spring Boot and test them using the Mockito framework. If you are not familiar with unit testing, see my post on Medium. For those who are impatient, you can find the source code on GitHub. HTTP Verbs Overview The most-commonly-used HTTP verbs are […]

AWS Certified Solutions Architect: Notes and Practice Questions

I gathered my study notes and practice questions for the AWS Certified Solutions Architect Associate exam. You can download it at the end of the post. I created the content so that I could review it later on. It might help you along with other resources. However, do not expect a comprehensive document 🙂 Although […]

AWS Certified Solutions Architect – EBS Study Questions

What is Amazon Elastic Block Store (EBS)? Amazon Elastic Block Store (EBS) is an easy to use, high performance block storage service designed for use with Amazon Elastic Compute Cloud (EC2) for both throughput and transaction intensive workloads at any scale What are the features of Amazon EBS? EBS volumes are created in a specific […]

AWS Certified Solutions Architect – EFS Study Questions

General What is mount target? Can you mount an EFS file system in more than one VPC at a time? Can you use EFS file system in multiple VPCs at a time? Can EC2 instances in one VPC can access EFS file systems in another VPC? If yes, how do you do it? Can EFS […]

AWS Certified Solutions Architect – S3 Study Questions

What are the S3 core concepts? What are the bucket properties? What is server access logging? Which HTTP status code is generated for successful S3 uploads? Control access to buckets using bucket ACL or Bucket Policies. What is the difference between them? What is the benefits of the consolidated billing? Are S3 objects are […]

AWS Certified Solutions Architect – API Gateway Study Questions

With what backends can Amazon API Gateway communicate? Can you use the lambda function from another account for an API Gateway? What is VPC link is used for? You create an endpoint to your VPC by setting up a VPC link between X and Y? How do you improve the API performance? What are the […]

Java SE 8/11 Programmer II Exam Series: Concurrency (Part 1)

Introduction This post is currently in progress… In this post, we will look at the exam objective; create worker threads using Runnable, Callable, and use an ExecutorService to concurrently execute tasks. Note that this is also a part of the Java SE 11 Programmer II Certification. Runnable Interface Runnable interface Usages of Runnable interface Creating a […]

Java SE 8/11 Programmer II Exam Series: Exception Handling and Assertions

Introduction In this post, we will look at the following exam objectives. Note that this is also a part of the Java SE 11 Programmer II Certification. Use the try-with-resources construct Create and use custom exception classes Test invariants by using assertions Use the try-with-resources construct The new try-with-resources statement automatically closes all resources opened […]