Here’s an interview with a Java expert, where he discusses the future of the language, its evolution, and how it fits in with modern technologies. We cover legacy code, Kotlin migration, LTS releases, and what employers might be looking for in the coming years.
Interviewer:
Lately, there’s been a lot of chatter about whether it’s still worth learning Java. Some believe that, given the vast legacy of existing systems, the ongoing need to support and maintain them will guarantee demand for specialists, even though new projects can be developed in Kotlin. What’s your take on this? Is learning Java still relevant today?
Java Expert:
Absolutely. Java remains a cornerstone in the corporate world. Over the past two decades, it’s built a massive base of industrial and enterprise code—from banking and finance to government systems. Sure, Kotlin and other modern JVM languages are gaining traction, but Java is still the bedrock of that entire ecosystem. Learning Java gives you a solid grasp of object-oriented programming and the inner workings of the JVM, which in turn makes picking up Kotlin or other languages a lot easier down the line.
Interviewer:
Speaking of JVM languages, aside from Kotlin, what other languages run on the JVM?
Java Expert:
There are quite a few interesting options on the JVM:
- Scala: It blends object-oriented and functional programming and is particularly popular in big data environments (think Apache Spark).
- Groovy: A dynamic language perfect for scripting and creating domain-specific languages (DSLs). It’s also widely used in build tools like Gradle.
- Clojure: A Lisp-inspired language that focuses on functional programming with an emphasis on immutability and parallel processing.
- JRuby and Jython: These let you run Ruby and Python on the JVM, respectively.
- And then there are lesser-known ones like Ceylon and Xtend, which compile to Java code as well.
Interviewer:
People often say Java will be in demand “for many years” because of its legacy. How long do you think that really is—10, 20 years, or even longer?
Java Expert:
It’s hard to pinpoint an exact number, but most experts agree that Java will remain relevant for at least another 10–20 years. There are two big reasons:
- Legacy and critical systems: Tons of mission-critical systems are built in Java. Rewriting them is risky, expensive, and time-consuming.
- Economic factors: Companies aren’t eager to scrap tried-and-tested systems just to chase the latest trends, so there’s a built-in demand for Java specialists for the foreseeable future.
Interviewer:
Some argue that existing systems can gradually be migrated to Kotlin, especially as new developers enter the market. Do you think that in five years most projects might be rewritten in Kotlin?
Java Expert:
That scenario sounds a bit too optimistic. In reality, what we’re seeing is a gradual migration: new modules or features might be written in Kotlin, but the core, mission-critical parts tend to stay in Java. Rewriting large, mature systems isn’t just a technical hurdle—it’s also an organizational challenge that requires deep architectural knowledge, which comes with experience. So, a full-scale swap from Java to Kotlin in just five years is pretty unlikely.
Interviewer:
What about libraries? Some say that Java libraries will eventually be rewritten in Kotlin, making Java obsolete. What’s your view?
Java Expert:
In practice, most Java libraries are here to stay. Here’s why:
- Reliability: These libraries have proven themselves over time. Rewriting them could introduce new bugs and issues.
- Interoperability: Kotlin is 100% interoperable with Java. This means Kotlin projects can use existing Java libraries without a hitch, reducing the need to rewrite them.
- In short, we’re more likely to see a coexistence of both languages rather than a complete abandonment of Java.
Interviewer:
There’s also been a lot of talk about Java’s rapid evolution with LTS releases like Java 17 and Java 21. Now with Java 23 out and it’s already February 2025, is Java keeping pace with modern trends?
Java Expert:
Definitely. Java continues to evolve—Java 23 is a clear example, packed with innovative features and improvements. However, large corporate projects tend to stick with LTS releases like Java 17 or Java 21 because they offer long-term support and stability. The non-LTS versions, like Java 23, are more like a playground for new ideas, and their features eventually make their way into the next LTS version. So yes, Java’s development pace is very much in line with today’s requirements.
Interviewer:
Many employers are actively seeking Java developers right now, but what about five years down the line? Given that foundational OOP skills can also be learned with languages like C#, will employers still be hiring Java specialists?
Java Expert:
Great question. The long-term demand for Java developers comes down to a few key factors:
- Legacy and Stability: Many critical systems are built in Java, so maintaining them requires developers who really understand the nuances of the language and its ecosystem.
- Core Skills: Java teaches you a deep understanding of object-oriented programming, application architecture, and JVM internals. These skills are universally valuable, regardless of whether you later pick up C# or Kotlin. (Of course, C# offers its own benefits, but when we’re talking about the JVM ecosystem, it’s a different ballgame.)
- Gradual Tech Integration: Even as new projects adopt modern JVM languages, the main codebases in many organizations will continue to run on Java, ensuring a steady demand for experienced Java developers.
Interviewer (conclusion):
Thanks for the insightful answers! It sounds like Java isn’t just about learning the basics—it’s an investment in your future in a tech landscape that’s constantly evolving.
Java Expert:
Exactly. The tech industry is always changing, and adaptability is key. Java remains a robust foundation for countless solutions, and mastering it sets you up for long-term success in your career.
In summary, despite the emergence of alternatives and evolving technologies, Java still holds a crucial position in the corporate world. The gradual adoption of new tools doesn’t mean we’ll be abandoning this time-tested platform—it just means developers get to expand their toolkit, making them more versatile and in demand.
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