Скачать или смотреть Downgraded Java to JDK 1.1 After 30 Years… It Was a Disaster (part 1)

How should we change Java 23 code for it to run on Java 1.1?

We go line by line, removing modern features like records, sealed classes, switch expressions, var, and more. Each step reveals what breaks, how to rewrite it, and what you lose in the process.

If you’ve ever wondered how far modern Java has drifted from its roots — this is your deep dive into that gap.

This is Part 1 of the Java Downgrade Challenge, where we descend version by version until we reach Java 8.

Subscribe to our channel to find out how we go even deeper — all the way down to Java 1.1. Stay tuned!

Can modern code survive its own history? Let’s find out!

00:00 Introduction: Downgrading Java Step by Step
00:44 Java 23: Sealed Classes, Records, Pattern Matching
02:02 Java 22: Markdown Javadoc No Longer Supported
02:28 Java 21: Underscore Parameters Removed
02:58 Java 20: Pattern Matching and Collections API Break
04:34 Java 19–17: Minor Differences
05:34 Java 16: Sealed and Records as Preview Features
06:10 Java 15: Text Blocks Still Supported
07:27 Java 14–10: Loss of `var` in Lambdas
08:44 Java 8: Manual Rewrites and Compatibility Workarounds
09:59 Summary: Feature Loss Overview
10:16 Planned: Downgrade to Java 1.1