If you are getting the below exception during you start your spring boot application.

The application failed to start due to an exception org.springframework.boot.web.server.PortInUseException: Port 8081 is already in use

Step 1:

Open up cmd.exe (note: you may need to run it as an administrator, but this isn’t always necessary)…

…The story will tell you about the design principle you should consider during your coding. The example will cover java.

Why you should be using solid principles? how you can connect these with your controller, handler, action, service, repository class in java.

Single Responsibility Principle

A class should have one, and only one

This story will tell about the basic thing that will come into the mind of the developer when using spring bean.

What is actually spring bean? Is there any other naming convention used?

Spring bean is an object that forms your application's backbone and is managed by the Spring Ioc…

This story will explain the spring container and how its works

The org.springframework.beans and org.springframework.context packages are the basis for Spring Framework’s IoC container. The BeanFactory the interface provides an advanced configuration mechanism capable of managing any type of object. ApplicationContext is a sub-interface of BeanFactory.

Container Overview

The org.springframework.context.ApplicationContext

The story will tell you about the timeout or the configuration we need to know about implementing the ReplyingKafkaTemplate in your project.

ReplyingKafkaTemplate: KafkaTemplate that implements request/reply semantics. for more please visit https://shuaibabdulla40.medium.com/apache-kafka-request-reply-semantics-implementation-replyingkafkatemplate-5bf64958268c

When you have a replay topic is shared with multiple consumers you should be careful during the…

The story will tell about the scenario of the application failed to start due to an exception org. spring framework.beans.factory.NoUniqueBeanDefinitionException: No qualifying bean of type.

I will explain the one scenario that happens. …

The story will explain how Kafka is working in a bit of depth.

What is Apache Kafka?

Apache Kafka is a horizontally scalable,fault-tolerant, distributed streaming platform.

  • Deliver the messages to consumers when they need them.

Kafka combines three key capabilities so you can implement use cases for event streaming end-to-end…

This story is about the issue faced while developing when you want to connect your colleague Kafka server.


While trying to connect the Kafka tool will say unreachable to the Kafka server.

Steps to follow

As the Kafka config will contain the below structure.

This will tell you how you can manage your DB scripts in your project.

Applying Continuous Delivery means to automate the delivery pipeline and to release frequently. However, databases are a big challenge, because with every deployment we may need to update and migrate our database before we can deploy…

When you try to add multiple custom validation as below for reactive form in angular.

constructor(fb: FormBuilder, private cadastroService:CadastroService) {
this.signUp = fb.group({
"name": ["", Validators.compose([Validators.required, Validators.minLength(2)])],
"email": ["", Validators.compose([Validators.required, Validators.email])],
"phone": ["", Validators.compose([Validators.required, Validators.minLength(5)])],
"cpf": ["", Validators.required, …

Shuaib Abdulla

Java 8 | Spring | React | Angular | CI/CD | Microservices | Monitoring |Apache Kafka. https://www.linkedin.com/in/shuaib-kunhabdulla-83780188

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