10 Hard Skills Every Java Developer Should Have
17 Mar

10 Hard Skills Every Java Developer Should Have

Mahipal Nehra

One of the world's most popular programming languages is Java. It is an object-oriented language used to build applications for various platforms. Java developers are highly demanded due to the language's versatility and popularity. However, Java developers need to possess a set of specific hard skills.

Throughout this article, we will discuss ten hard skills every Java developer should have to succeed in their careers. So, without further ado, let’s get started.

Top 10 Java Developer's Hard Skills

Here is the list of top 10 Hard Skills that Every Java Developer Should Have.

  1. Object Oriented Programming (OOP) Concepts

  2. Data Structures and Algorithms

  3. Architectural Patterns

  4. Design Principles

  5. DevOps Tools

  6. CI/CD

  7. Java Frameworks & Libraries

  8. Java Software Testing Tools

  9. Big Data

  10. APIs

So, let’s look at these skills to understand why they are essential for a Java developer.

1. Object Oriented Programming (OOP) Concepts

OOP is all about creating objects that contain methods and data. Being an Object Oriented Programming Language, Java uses objects as the primary source for implementing what happens to the code.

Read: Data-Oriented Programming in Java

OOP concepts include class, objects, methods, abstraction, polymorphism, encapsulation, inheritance, user-defined and predefined types, operations, etc., to make code easier to execute, maintain, modify, and debug.

OOP is the basis of Java, so you need to know how to work around its concepts to create a successful program.

2. Data Structures and Algorithms

Data structures define the format of processing, arranging, storing, and accessing raw/complex data. Some data structures in Java code are arrays, linked lists, stacks, queues, binary trees, heaps, graphs, hashing, and binary search trees.

Read: Data Structures

On the other hand, algorithms are instruction sequences that help complete a task at a given time.

Java developers use data structures to collect and organize data and algorithms to manipulate data structures. Therefore, the more you clarify the concept of data structures and algorithms, the better the Java developer you will become.

3. Architectural Patterns

Software architecture is a software application's blueprint, showing the software's overall structure, components, implementations, and interactions. It allows development teams to communicate how a software system will be developed.

And there are a lot of predefined software architecture components that solve a set of recurring problems known as architectural patterns.

Read: Software Architect Roadmap 2023

To be a successful Java software developer, it is crucial to understand different architectural patterns as well as when and how to implement them.

Some popularly used architectural patterns you will encounter are Layered Patterns, Service-Oriented Architecture, Microservices, Multitier architecture, Pub-Sub patterns, and more.

4. Design Principles

Next on the list comes design patterns.

Design patterns are well-described strategies to solve common problems in software development. Put simply, design patterns are ideas, not a solution or implementations. It can be divided into creational, behavioral, and structural design patterns.

Read: Custom Web Application Design Patterns

Using design patterns in Java, you can make reusable, flexible, and easily maintainable code.

5. DevOps Tools

The blend of Development and Operations comprises what we know as DevOps. It allows a development team to handle the entire software application lifecycle by promoting collaboration between developers and IT operations (quality assurance engineers and system admins).

Read: DevOps Engineer Roadmap 2023

As a Java developer who will be working with the development and operations team, some of the DevOps tools you need to be aware of are:

  • Version control systems (Git, GitHub, and BitBucket)

  • Containerization Tools (Docker, Mesos, and Kubernetes)

  • Performance Monitoring (AppDynamics, and Prometheus)

  • Configuration Management Tools (Puppet, Ansible, and Chef)

6. CI/CD

CI/CD is short for Continuous Integration and Continuous Development. CI /CD automates processes to commit code into production, including build, test, deploy phases, and infrastructure provisioning.

Read: Continuous Testing

Developers can modify code using CI/CD tools and get them automatically tested, pushed, and deployed. Jenkins, CircleCI, Travis CI, Buddy, Bamboo, etc., are examples of CI/CD tools you can work with.

Learning CI/CD tools will allow you to deliver software quickly and efficiently.

7. Java Frameworks

Frameworks refer to the prewritten code bodies that act as templates. Developers use them to create web apps without creating everything from scratch.

Read: Top 10 Java Libraries 2023

Java frameworks include predefined functions and classes used to process, manage, and input devices that interact with system software. Moreover, a framework can be a collection of two or more libraries.

Spring, Quarkus, Hibernate, JavaServerFaces (JSF), Vaadin, Struts, and Blade are some Java frameworks you should learn to thrive in your career as a developer.

8. Java Software Testing Tools

Software testers, developers, and quality assurance (QA) teams use testing tools to ensure the performance and quality of the software. With the help of software testing tools, developers can improve code quality, reduce the duration of testing, and deliver a high-quality product.

Even if you are not bound to become experts in using testing tools, knowing a few will be beneficial to make your code robust, bug-free, and secure.

You can use a few software testing tools: Selenium, Cucumber, JMeter, Appium, and Tosca.

9. Big Data

As the world becomes increasingly data-driven, the demand for professionals who can manage and analyze large amounts of data is skyrocketing. And the flexibility and scalability that Java offers make it an ideal choice for developing big data applications. Java developers who learn Big Data and know how to work with popular big data frameworks like Apache Spark and Apache Hadoop have a massive advantage in the industries as they can help companies make sense of their data to make informative decisions.

10. APIs

Application Programming Interfaces allow developers to easily create complex application functionalities by abstracting complex code and providing simpler syntax.

Read: Principles of Web API Design

As a Java developer, you must learn about JSON, REST, Gson, XML, Logging APIs, Collection APIs, and Data & Time APIs that will help you manipulate documents, fetch data from the server, and communicate with third-party applications and services.


Whether you are a developer or a business person, learning and adopting some of these top Java hard skills is crucial for the success of a project.

But we also know that, with the advent of new tools and technologies, you cannot stop learning new things if you really want to succeed.

Besides, if you want to develop a Java-based web application/software for your business, hire developers with relative experience in the field from companies like Decipher Zone Technologies.

Posted by Mahipal Nehra | Posted at 17 Mar, 2023 Web