Java on SivaLabs

Should I use a framework or libraries?

Mon, 22 Jan 2024 23:29:17 +0000

In the software development world, trends come and go, and often we go through the same cycle again and again. It seems 2024 is the year of “Framework vs Libraries” debate. I mean this debate is not new, but it is getting louder again.

Spring Boot + jOOQ Tutorial - 5 : Fetching Many-to-Many Relationships

Thu, 26 Oct 2023 00:30:00 +0000

In the previous tutorial, we have learned how to fetch One-to-Many relationships using jOOQ. In this tutorial, we will learn how to fetch Many-to-Many relationships using jOOQ.

Spring Boot + jOOQ Tutorial - 4 : Fetching One-to-Many Relationships

Mon, 23 Oct 2023 00:30:00 +0000

In the previous tutorial, we have learned how to fetch One-to-One relationships using jOOQ. In this tutorial, we will learn how to fetch One-to-Many relationships using jOOQ.

Spring Boot + jOOQ Tutorial - 3 : Fetching One-to-One Relationships

Thu, 19 Oct 2023 00:30:00 +0000

In the previous tutorial, we have learned how to implement basic CRUD Operations using jOOQ. In this tutorial, we will learn how to fetch One-to-One relationships using jOOQ.

Spring Boot + jOOQ Tutorial - 2 : Implementing CRUD Operations

Mon, 16 Oct 2023 00:30:00 +0000

In the previous tutorial, we have seen how to generate jOOQ code using the testcontainers-jooq-codegen-maven-plugin and use jOOQ Typesafe DSL to execute SQL queries. In this tutorial, we will learn how to implement basic CRUD Operations using jOOQ.

Spring Boot + jOOQ Tutorial - 1 : Getting Started

Thu, 12 Oct 2023 00:30:00 +0000

jOOQ is a Java persistence library that provides SQL DSL for writing typesafe SQL queries. It supports most of the popular databases like MySQL, PostgreSQL, Oracle, SQL Server, and many more. In this tutorial, we will learn how to get started with jOOQ for implementing persistence layer in a Spring Boot application. You can also use jOOQ in other JVM based languages like Kotlin, Scala, etc.

MyBatis Tutorials

Tue, 18 Jul 2023 02:32:39 +0000

MyBatis

Should you use Lombok? Or, is it bad for you?

Mon, 24 Apr 2023 23:29:17 +0000

I’m a happy Lombok library user. I found this library a decade ago, and I’ve been using it ever since. I don’t remember facing any major problems with it so far.

However, I see a few people that I greatly admire and learn from often complain that Lombok is very bad, and you should avoid it. Obviously, I am curious to know what am I missing? I know a couple of scenarios where using Lombok brings some challenges. Apart from it, I really enjoy using the Lombok library.

My attempt to understand why people perceive Java as complex

Sun, 03 Apr 2022 23:29:17 +0000

I work as an Architect/TechLead/SeniorDeveloper depending on client engagement. And, Java is the primary programming language that I have used most of my career. In recent years I got an opportunity to work with Go, NodeJS and .Net Core technologies too. I find Java, especially with Spring Boot, a solid platform to build enterprise grade applications.

Improve JPA application performance using HypersistenceOptimizer

Fri, 01 Jan 2021 23:29:17 +0000

In Java world, Hibernate/JPA is the most popular ORM framework. Also, JPA/Hibernate is a very controversial topic because some people don’t like it at all. It is very understandable though.

Many people start using JPA/Hibernate with minimal knowledge and keep adding logic (read as “annotations”) as and when required to get the job done. While checking the overall application performance, most of the time people realize it’s because of poor performance of persistence layer.

JOOQ Tutorials

Mon, 30 Nov 2020 02:32:39 +0000

jOOQ

Tutorials

Mon, 30 Nov 2020 02:32:39 +0000

Spring AI

Spring Boot

Spring Security OAuth 2.0 Tutorials

Spring Cloud

Microservices

Kubernetes

jOOQ

MyBatis

Thoughts & Opinions

Philip's Testing Spring Boot Applications Masterclass Course Review

Wed, 14 Oct 2020 23:29:17 +0000

If you ever worked on a large project which doesn’t have any tests then you know how painful it is to work on such codebase.

You know what is more painful? Working on a project which has plenty of USELESS tests written for the sake of passing minimum code coverage requirement.

LocalStack Spring Boot Starter Tutorial

Tue, 15 Sep 2020 23:29:17 +0000

I was working on a Spring Boot application which is planned to deploy on AWS and, we were using S3, SQS and RDS services.

LocalStack provides an easy-to-use test/mocking framework for developing AWS based Cloud applications.

All the resources you ever need as a Java & Spring application developer

Sun, 13 Sep 2020 23:29:17 +0000

Nowadays software development is a challenging task as the number of programming languages, frameworks, libraries are increasing rapidly day by day. Luckily, the number of resources to learn on the internet for free also increased a lot. There are a ton of free resources to learn almost everything on the internet. There are lots of official documentation, blog posts, Udemy courses, YouTube videos etc.

Remote debugging Spring Boot application

Sat, 30 May 2020 23:29:17 +0000

We all know how to run Spring Boot application in debug mode from our favorite IDEs(IntelliJ IDEA, Eclipse etc) and debug the code. Recently I had to debug a Spring Boot application which is running on a remote server.

There is already lot of information on the Internet on how to remote debug java applications, but some approaches didn’t work for me. So, here I would like to share my findings.

What I Learned in Week-14, 2020

Sun, 05 Apr 2020 23:29:17 +0000

It’s been tough time for everyone due to the Corona virus situation. Staying at home for weeks and weeks is not easy, but it is very necessary thing to do so that we don’t spread the virus.

However, if I look on the bright side I used to spend minimum 3 hours for office commute everyday. Now I am using that time for various other activities including learning some new things.

Imposing Code Structure Guidelines using ArchUnit

Wed, 01 Apr 2020 23:29:17 +0000

While building the software, we all agree, as a team, to follow a set of guidelines which are typically considered as best practices. But during the development, developers might violate those guidelines unknowingly or ignorance. Typically, we rely upon code reviews or code quality checking tools like SonarQube, PMD, etc. to check for such violations. But some of the guidelines could be opinionated decisions which might not be able to automate using SonarQube, PMD etc.

What I Learned in Week-11, 2020

Sat, 14 Mar 2020 23:29:17 +0000

I come across many blog posts from various sources like Twitter, StackOverflow, etc., and some of them are very helpful. Also, in day-to-day work I learn a few new things, explore some new tools. Usually I keep track of this information using Browser Bookmarks and Pocket.

I thought maybe this information could be useful for others too. So, I am going to share it weekly on my blog.

Kafka Tutorial - Producer and Consumer using Spring Boot

Mon, 24 Jun 2019 02:29:17 +0000

In the previous post Kafka Tutorial - Java Producer and Consumer, we learned how to implement a Producer and Consumer for a Kafka topic using the plain Java Client API.

In this post, we are going to look at how to use Spring for Kafka, which provides a high-level abstraction over the Kafka Java Client API to make it easier to work with Kafka.

Kafka Tutorial - Java Producer and Consumer

Fri, 21 Jun 2019 02:29:17 +0000

Kafka, depending on how you use it, can be seen as a Message Broker, Event Store, or a Streaming Platform, etc. Kafka became a preferred technology for many modern applications because of various reasons, like:

Kafka can be used as an Event Store if you are using an event-driven microservices architecture.
Kafka can be used as a Message Broker to enable communication across multiple applications.
Kafka can be used as a streaming platform for processing events in real-time. etc. etc.

Spring Cloud Tutorials – Auto Refresh Config Changes using Spring Cloud Bus

Mon, 14 Aug 2017 12:30:43 +0000

In the previous article, Introduction to Spring Cloud Config Server, we have seen how to use Spring Cloud Config Server.

But the problem is that to reload the config changes in Config Client applications, we need to trigger the /refresh endpoint manually. This is not practical or viable if you have a large number of applications.

Spring Cloud Tutorials – Introduction to Spring Cloud Config Server

Mon, 14 Aug 2017 03:35:07 +0000

Spring Boot provides a lot of flexibility in externalizing configuration properties via properties or YAML files. We can also configure properties for each environment (dev, qa, prod, etc.) separately using profile-specific configuration files such as application.properties, application-dev.properties, application-prod.properties, etc. But once the application is started, we cannot update the properties at runtime. If we change the properties, we need to restart the application to use the updated configuration properties.

My Life as a Software Developer in India

Mon, 06 Jul 2015 16:17:00 +0000

I am Siva, working as a Software Developer in Hyderabad, India. Working as a Software Developer is very exciting as you see new things coming in every day. If there are no new things, at least we put a new fancy name to some old concept and celebrate (#microservices) :-). But in my opinion, working as a Software Developer in India is a little bit different and hard too. A few things are good, and a few things are bad.

A Developers Perspective on Spring vs JavaEE

Mon, 15 Jun 2015 13:04:00 +0000

In the Java community, Spring vs. JavaEE is a never-ending debate. In such debates, people form two groups consisting of evangelists, architects, and hardcore fans of one platform and debate endlessly. Those who participate in the debates may be architects who are responsible for platform selection. But what would developers think about this Spring vs. JavaEE debate?

I am a Java developer who uses both Spring and JavaEE, and I am not part of the Spring or JavaEE fan club. Here, I would like to share my own thoughts on this epic Spring vs. JavaEE debate.

Clean Code: Don't mix different levels of abstractions

Sun, 29 Dec 2013 00:53:00 +0000

We spend more time reading code than writing it. So if the code is more readable, it will obviously increase developer productivity.

Many people associate the readability of code with coding conventions like following standard naming conventions, closing files, DB resources, etc. When it comes to code reviews, most people focus on these trivial things only, like checking for naming convention violations or whether resources are properly released in a finally block.

MyBatis Tutorial : Part4 – Spring Integration

Wed, 24 Oct 2012 00:40:00 +0000

MyBatis Tutorial: Part1 – CRUD Operations

MyBatis Tutorial: Part-2: CRUD operations Using Annotations

MyBatis Tutorial: Part 3 – Mapping Relationships

MyBatis Tutorial : Part4 – Spring Integration

MyBatis-Spring is a sub-project of MyBatis that provides Spring integration support, which drastically simplifies MyBatis usage. For those who are familiar with Spring’s Dependency Injection process, using MyBatis-Spring is very simple.

First, let us see the process of using MyBatis without Spring.

Create SqlSessionFactory using SqlSessionFactoryBuilder by passing mybatis-config.xml, which contains DataSource properties, a list of Mapper XMLs, TypeAliases, etc.
Create an SqlSession object from SqlSessionFactory.
Get a Mapper instance from SqlSession and execute queries.
Commit or roll back the transaction using the SqlSession object.

With MyBatis-Spring, most of the above steps can be configured in the Spring ApplicationContext, and SqlSession or Mapper instances can be injected into Spring Beans. Then we can use Spring’s TransactionManagement features without writing transaction commit/rollback code all over the place.

MyBatis Tutorial: Part 3 – Mapping Relationships

Sun, 21 Oct 2012 14:07:00 +0000

In this post, let us see how to use MyBatis ResultMap configuration to map relationships.

MyBatis Tutorial: Part1 – CRUD Operations

MyBatis Tutorial: Part-2: CRUD operations Using Annotations

MyBatis Tutorial: Part 3 – Mapping Relationships

MyBatis Tutorial : Part4 – Spring Integration

To illustrate, we are considering the following sample domain model:

There will be Users and each User may have a Blog and each Blog can contain zero or more posts.

MyBatis Tutorial: Part-2: CRUD operations Using Annotations

Sun, 21 Oct 2012 11:49:00 +0000

In this post, I will explain how to perform CRUD operations using MyBatis’s annotation support without needing to configure queries in XML mapper files.

MyBatis Tutorial: Part1 – CRUD Operations

MyBatis Tutorial: Part-2: CRUD operations Using Annotations

MyBatis Tutorial: Part 3 – Mapping Relationships

MyBatis Tutorial : Part4 – Spring Integration

Step#1: Create a table BLOG and a java domain Object Blog.

CREATE TABLE blog 
(
 blog_id int(10) unsigned NOT NULL auto_increment,
 blog_name varchar(45) NOT NULL,
 created_on datetime NOT NULL,
 PRIMARY KEY (blog_id)
) ENGINE=InnoDB DEFAULT CHARSET=latin1;

package com.sivalabs.mybatisdemo.domain;

import java.util.Date;

public class Blog 
{
 private Integer blogId;
 private String blogName;
 private Date createdOn;
 
 //Setters and getters
 
 @Override
 public String toString() {
 return "Blog [blogId=" + blogId + ", blogName=" + blogName
 + ", createdOn=" + createdOn + "]";
 }
}

Step#2: Create UserMapper.java interface with SQL queries in Annotations.

MyBatis Tutorial: Part1 – CRUD Operations

Sun, 21 Oct 2012 11:10:00 +0000

MyBatis is an SQL Mapper tool which greatly simplifies database programming when compared to using JDBC directly.

MyBatis Tutorial: Part1 – CRUD Operations

MyBatis Tutorial: Part-2: CRUD operations Using Annotations

MyBatis Tutorial: Part 3 – Mapping Relationships

MyBatis Tutorial : Part4 – Spring Integration

Step1: Create a Maven project and configure MyBatis dependencies.

<project xmlns="http://maven.apache.org/POM/4.0.0" 
 xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
 xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 
 http://maven.apache.org/xsd/maven-4.0.0.xsd">
 <modelVersion>4.0.0</modelVersion>

 <groupId>com.sivalabs</groupId>
 <artifactId>mybatis-demo</artifactId>
 <version>0.0.1-SNAPSHOT</version>
 <packaging>jar</packaging>

 <name>mybatis-demo</name>
 <url>http://maven.apache.org</url>

 <properties>
 <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
 </properties>

 <build>
 <plugins>
 <plugin>
 <groupId>org.apache.maven.plugins</groupId>
 <artifactId>maven-compiler-plugin</artifactId>
 <version>2.3.2</version>
 <configuration>
 <source>1.6</source>
 <target>1.6</target>
 <encoding>${project.build.sourceEncoding}</encoding>
 </configuration>
 </plugin>
 </plugins>
 </build>

 <dependencies>
 <dependency>
 <groupId>junit</groupId>
 <artifactId>junit</artifactId>
 <version>4.10</version>
 <scope>test</scope>
 </dependency>
 <dependency>
 <groupId>org.mybatis</groupId>
 <artifactId>mybatis</artifactId>
 <version>3.1.1</version>
 </dependency>
 <dependency>
 <groupId>mysql</groupId>
 <artifactId>mysql-connector-java</artifactId>
 <version>5.1.21</version>
 <scope>runtime</scope>
 </dependency>
 </dependencies>
</project>

Step#2: Create the table USER and a Java domain Object User as follows:

Keep The Code Clean: WatchDog & SpotTheBug Approach

Tue, 28 Aug 2012 04:55:00 +0000

Before discussing the WatchDog & SpotTheBug Approach, let me give a brief context on the need for this.

Three months back, I was asked to write core infrastructure code for our new application, which uses all the latest and greatest technologies. I have written the infrastructure code and implemented two use cases to demonstrate which logic should go into which layer, and the code looks good (at least to me :-)). Then I moved on to my main project, and I was hearing that the project that I designed (from now onwards, I will refer to this as ProjectA) is going well.

When to use RequestDispatcher.forward() and response.sendRedirect()?

Thu, 25 Aug 2011 00:35:00 +0000

Many people know how RequestDispatcher.forward() and response.sendRedirect() work.

RequestDispatcher.forward() is generally called server-side redirection and is used to forward to a resource within the same application. That resource could be a JSP or another servlet.

response.sendRedirect() is generally called client-side redirection, as it issues a new request from the browser. This method is used to redirect to another resource within the same application, to a resource in some other application running in the same web container, or to any other resource running in some other web container.

10 things to become an outstanding Java developer

Wed, 26 Jan 2011 07:11:00 +0000

If you are a Java developer and passionate about technology, you can follow the tips below, which will make you an outstanding Java developer.

1. Have a strong foundation and understanding of OO Principles

For a Java developer, having a strong understanding of Object-Oriented Programming is a must. Without a strong foundation in OOPS, one can’t realize the beauty of an object-oriented programming language like Java. If you don’t have a good idea of what OOPS is, even though you are using an OOP language, you may still be coding in a procedural way. Just studying the definitions of OO principles won’t help much. You should know how to apply those OO principles when designing a solution in an OO way. So, one should have strong knowledge of object modeling, inheritance, polymorphism, and design patterns.

Welcome note

Sun, 21 Dec 2008 08:05:00 +0000

Hi all, Welcome, folks. This is a blog where you can find tutorials on various Java and JavaEE technologies and have discussions regarding technical problems and application development-related issues.

I used to blog at https://sivalabs.blogspot.com/, but now moved to https://sivalabs.in.