Java developer must-have skills

1. Overview

Java developer needs to have core skills to build enterprise-level software. In this tutorial, we will see the must-have skills for a java developer.

2. Java Developer Must Have Skills

For a java developer to develop and integrate business applications, the person needs to have core skills. The person needs to have an understanding of the customer’s vision and business requirements to develop an enterprise-class application. The programmer needs to practice every day java for at least two hours. He or she needs to be aware of Core Java, Java EE, Servlets, JSP, Hibernate, Spring frameworks, Android, Docker, and Front end technologies & technology stacks like MERN, MEAN. The person needs to know object-oriented programming concepts. The programmer needs to understand API Centric applications to web services, multi-threading, spring boot, cloud deployment, java virtual machine, microservices architecture, dependency injection, and MVC framework

I am sure you would have heard the above regarding skills for a java developer to have. This article helps in defining core skills to move the programmer to the developer level. The skills are categorized into the core (must-have), advanced and complex skills.

Java developer - Must-Have Skills
Must-Have Skills

“Learning the art of programming, like most other disciplines, consists of first learning the rules and then learning when to break them.”

Joshua Bloch, Effective Java Programming Language Guide

Now let us look at must-have skills for a person to become a Java developer.

2.1 Data Structures

A person needs to have problem-solving and software development skills to become a java developer. Data organization and real-life solutions are the fundamental concepts that the developer needs to have. The data structures that the developer needs to learn are listed below:

It is important for the developer to know how to choose a data structure and which one to pick for a particular scenario. The goal is to consume lesser memory and solve the problem in a short time while choosing the data structure.

2.2 Algorithms

The algorithms are very important concepts to learn for a developer. The performance of different algorithms in time and space is an important factor in choosing the right algorithms. The list of algorithms for a developer to know are as below:

  • Hashing
  • Sorting
  • Searching
  • Recursion
  • Caching

2.3 Security

The developer needs to know the security aspects of the web/desktop/mobile application. The person needs to learn the encryption and decryption of the data. The developer needs to know the different types of security attacks listed below:

  • Malware
  • Denial of Service
  • Man in the middle
  • Spear Phishing
  • Drive-by
  • Password
  • SQL Injection
  • Cross-site Scripting
  • Eavesdropping
  • Birthday

The developer needs to know RSA, AES and other types of cryptography algorithms. The person needs to have an understanding of public-key cryptography.

2.4 Database

The developer needs to know the development of database-driven applications. The person needs to know how to handle create, read, update and delete JDBC operations using SQL on relational and no SQL database. The developer needs to have an understanding of database security and secure the data in the database storage. He or she needs to have a basic understanding of JPA (Java Persistence API) and ORM (Object Relational Mapping) Frameworks.

Java developer - CRUD Operations
CRUD Operations

2.5 Performance

The developer needs to know Java application performance tuning and profiling. The person needs to learn the virtual machine, memory management, class loading, and reflection concepts. The developer needs to have skills to resolve issues related to a memory leak, performance, and crashes. He or she needs to know how to develop web applications with logging, monitoring and debugging frameworks & tools.

Java developer - Performance Concepts
Performance Concepts

2.6 Source Control

The developer needs to know source control and versioning concepts & operations. The person needs to learn software such as Git, SVN, Gitlab, BitBucker, and Mercurial source control management tools. The person should know how to create branches and merge them with master branch. He or she should be able to create pull requests. The developer should be able to compare different versions and see the history of an artifact.

2.7 Operating System

A developer needs to know the basics of the operating system. The person needs to be aware of memory management, process communication, distributed systems, threads, blocking, and file handling concepts. The developer needs to know the popular operating systems such as Linux, Mac, Unix, and Windows. The person should learn mobile operating systems like Android and IOS.

2.8 Networking

Developers should know the networking basics and concepts listed below:

  • Sockets
  • System Programming
  • Network programming
  • HTTP protocol
  • Network Traffic analysis
  • Understanding of FTP, Telnet, SSL, and other protocols

2.9 Software Development Life Cycle

A developer needs to know the software development life cycle. He or she needs to know the phases in the lifecycle. The person needs to understand requirements gathering, architecture, design, development, testing, deployment and maintenance phases. The developer should be able to unit test and develop the functional & regression tests.

Java developer - SDLC

2.10 IDE

The developer needs to know how to develop software using IDEs such as Eclipse, Netbeans, and IntelliJ. He or she should learn how to compile and debug the code. The person needs to know to check in the code and execute the application on the IDE.


2.11 Text Editors

The developer needs to know how to create applications using Text editors such as Notepad++, Sublime, Atom, Bracket, EMacs, and Edit Pad. He or she needs to know the keyboard shortcuts for improving personal productivity. The developer should be able to manage multiple versions of the files using text editors.

2.12 Build Tools

A java developer should be able to build java desktop, web and mobile applications using Ant, Maven, and Gradle build tools. He or she needs to have the unit tests, regression tests, and functional tests integrated with build to ensure build is not broken. The developer should be able to identify the dependencies for the build and configure the build tools for download.

2.13 DevOps

The developer needs to be aware of the usage of DevOps and continuous integration tools like Jenkins, Chef, Puppet, and Ansible. The person should be able to deploy the application after building using DevOps onto different cloud environments. The developer should be able to monitor the application using DevOps Framework.

3. Summary

To summarize, the must-have skills for a java developer which are core and basic are shown below:

Must-Have Skills

“time and tide wait for no man.”


As time passes, the developer needs to catch up with upcoming new technologies. He or she needs to update oneself with new skills to catch up with the pace of innovation in the Java world.

Bhagvan Kommadi

Bhagvan Kommadi is the Founder of Architect Corner & has around 19 years experience in the industry, ranging from large scale enterprise development to helping incubate software product start-ups. He has done Masters in Industrial Systems Engineering at Georgia Institute of Technology (1997) and Bachelors in Aerospace Engineering from Indian Institute of Technology, Madras (1993). He is member of IFX forum,Oracle JCP and participant in Java Community Process. He founded Quantica Computacao, the first quantum computing startup in India. Markets and Markets have positioned Quantica Computacao in ‘Emerging Companies’ section of Quantum Computing quadrants. Bhagvan has engineered and developed simulators and tools in the area of quantum technology using IBM Q, Microsoft Q# and Google QScript.
Notify of

This site uses Akismet to reduce spam. Learn how your comment data is processed.

Newest Most Voted
Inline Feedbacks
View all comments
4 years ago


4 years ago

Bullshit, the author wants to have a golden cow. This article is a series of make a wish. I am sure you dont need to know each an every algorithm or data structure or even understand a vision of the business guys. I respect the author for his CV but I think this article is just wrong. Java devs need to know Java the rest will be learned on the job.

Bhagvan Kommadi
Bhagvan Kommadi
4 years ago
Reply to  St1mpy

experience on the job will be added as a must have….

Back to top button