Software And Architecture

Let's walk through a basic example of how to set up and use Spring Cloud Config Server to manage configuration for multiple tenants in a Spring Boot Application. Step 1: Create a Spring Cloud Config Server Create a new Spring Boot project with the Spring Cloud Config Server dependency. <!-- pom.xml --> <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-config-server</artifactId> </dependency> Configure the Spring Cloud Config Server: // src/main/java/com/example/ConfigServerApplication.java import org.springframework.boot.SpringApplication; import org.springframework.boot.autoconfigure.SpringBootApplication; import org.springframework.cloud.config.server.EnableConfigServer; @SpringBootApplication @EnableConfigServer public class ConfigServerApplication { public static void main(String[] args) { SpringApplication.run(ConfigServerApplication.class, args); } } Configure the appl

Introduction This is a continuation to the post on exception handling on threads. For those interested in the background, please visit this link This post discusses on the topic "Can I use separate exception handlers for threads performing mission critical tasks vs non trivial tasks?" Per-Thread Exception Handler Let's us assume that we built a handler that wants to notify the support team that something has gone wrong in some special thread processing, like the one below (not really notifying anyone but helps correlate the context) class SupportNotificationExceptionHandler implements Thread . UncaughtExceptionHandler { @Override public void uncaughtException ( Thread t, Throwable e) { notifySupport (t, e); } private void notifySupport ( Thread t, Throwable e) { System . out . println ( "Notified support team on: " + e. getMessage () + " raised from : " + t. getName ()); } } Let us now apply the above special handle

Exception Handling There is always a requirement to handle all the NFR (Non-Functional Requirements) well in any application so that the application performs well in production and possess the excellent traceability and exception reporting mechanisms for better visibility on what happens in applications. Types of Exceptions We normally use exceptions within each domain of the application like Customers, Orders, Inventory etc. There are also a lot of custom exceptions that might be required when the application is built to capture, report the exceptions to the user. In this process, we can follow the below given process Base Exceptions There are multiple use-cases where we need separate exceptions to report multiple error conditions or cases, let us consider one such case for data validation. BaseValidationException import java.util.List; public class BaseValidationException extends RuntimeException { public BaseValidationException() { super(); } public BaseVali

What is AOP AOP stands for Aspect Oriented Programming. It is mainly used to implement the Cross-Cutting concerns in applications. These are used to reduce the mix of the business logic from the NFR (Non Functional Requirements) like logging, performance monitoring, validations etc. Also, these "Aspects" can be [should be] generalized and be located in a common library or package so that it can be easily upgraded / patched. Further, these Aspects are to be implemented without bringing-in these Aspects into every service or business logic layer so that they can be less invasive and like autowired to get the job done without being omni-present. Spring AOP helps us achieve this model by bringing in the support for the Aspects and help us wire these aspects at places where required. Core Terms / Concepts Aspect This is the cross cutting concern like logging / time measurement / validation etc. Join Point The method execution. (Example: Executing a service method like CustomerServ

Migrating from Springfox to OpenAPI 3 in Spring Boot Application This blogpost, I would like to share about the migration to OpenAPI 3 in my project application that is built using Java 8 and Spring boot.  I was working in a project that had a very old framework support and JDK. I was taking my free time whenever I find one and then did some upgrade to the core so as to get the application to be on the latest frameworks and get support if any issues. Why Upgrade? The reason for upgrade is to facilitate the following The application dependencies are up-to-date, meaning that when we face any issue or require any help, people will be able to help (Community support). Though we have support for the deprecated frameworks also from the vibrant community like Stackoverflow.com, better to be with the upgrades There might be limitations hindering in building new functionality or extending existing ones with the older versions, so a version upgrade to the latest will be always handy