Java 25 Essentials Master Every New Feature

Every new Java 25 LTS feature, coded and explained: language, concurrency, performance, security, profiling

What you'll learn

⚡ Write Java programs without class boilerplate using compact source files and instance main methods
⚡ Validate arguments before super() with flexible constructor bodies, and drop the static helper workarounds
⚡ Move request-scoped context from ThreadLocal to ScopedValue, including inheritance into virtual threads
⚡ Run parallel tasks as a single unit with StructuredTaskScope, with failure propagation, timeouts, and fallbacks
⚡ Use primitive types in instanceof and switch, including with record patterns and guarded cases
⚡ Replace long import blocks with module import declarations, and know when not to
⚡ Defer expensive initialization with StableValue, plus stable lists and maps for shards and registries
⚡ Cut JVM startup time with an AOT cache, and shorten warmup with AOT method profiling
⚡ Reduce heap usage with compact object headers, and understand what an object header actually holds
⚡ Configure generational Shenandoah, and choose the right collector for your workload
⚡ Derive keys with the new KDF API, and store passwords the way OWASP recommends
⚡ Read and write certificates and private keys with PEMDecoder and PEMEncoder
⚡ Profile production applications with JFR: CPU-time sampling, method timing, custom events, and event streaming
⚡ Speed up numeric and image processing code with the Vector API, and measure whether it was worth it
⚡ Know what Java 25 removed and whether your project is affected
⚡ Combine several of these features in one working application

Requirements

❗ Solid working experience with Java 17 or later
❗ Familiarity with records, sealed classes, and the basics of virtual threads. There are quick recaps where they're needed
❗ IntelliJ IDEA. The free Community Edition is all you need, and it's what the whole course is recorded in
❗ JDK 25. We cover the download and setup in section 1, so don't worry if you haven't installed it yet
❗ A willingness to type the code rather than just watch it

Description

Java 25 is the first Long-Term Support release since Java 21, and it arrived in September 2025 carrying 18 JEPs. Some of them change how you write everyday code. Others change how your application starts, how much memory it holds, and what you can see when something goes wrong in production.
This course covers all of them.
It's aimed at developers who already write Java for a living and want a straight answer to the question "what actually changed, and does any of it matter for my code?" We skip the loops-and-classes refresher and go straight to the new material, with working code you type alongside me in IntelliJ IDEA.
Most features get the same treatment. We start with the problem the feature solves, usually by writing the old code first and feeling where it hurts. Then comes the Java 25 version, which we run and compare. And we close each one with when to reach for it and when to leave it alone. Nothing here gets sold as a silver bullet, because none of it is.
A few of these features are still preview or incubator APIs. Structured concurrency, stable values, primitive patterns, and PEM encoding all need the --enable-preview flag, and the Vector API is still an incubator module. I flag that every time it comes up, along with the exact command line you'll need, so you always know whether you're looking at something you can ship on Monday or something to keep an eye on.
What the course covers
After setup, we work through the language changes: compact source files and instance main methods, flexible constructor bodies, primitive types in instanceof and switch, and module import declarations.
Concurrency comes next. Scoped values replace ThreadLocal for request-scoped context, and we walk through a real migration rather than a toy one. Structured concurrency gives you a task scope that cancels its children when one of them fails, and we build from the basics up to a service that fans out to several backends with timeouts and fallbacks.
On the performance side, stable values give you lazy initialization that the JVM can still treat as a constant. Ahead-of-time caching cuts startup with one extra flag, and AOT method profiling shortens warmup on top of that. Compact object headers shave 8 bytes off every object on the heap, roughly 22% less memory per object. Generational Shenandoah gets its own section, along with a practical guide to choosing a collector.
Security covers the new Key Derivation Function API with HKDF and PBKDF2, password storage done properly with constant-time comparison, and the PEM encoder and decoder that finally replaces all that manual Base64 string surgery.
The JFR section is the production diagnostics part: cooperative sampling, CPU-time profiling on Linux, method timing and tracing, custom events, and live event streaming with RecordingStream.
For the Vector API, we explain SIMD from first principles, then put it to work on image processing, and look at when vectorization pays off and when it just costs you complexity.
Then we build something. The projects section starts with a REST API on the JDK's built-in HTTP server and adds Java 25 features one at a time: scoped values for request context, structured concurrency for parallel backend calls, records with compact constructors for validation, the Vector API and stable values in a data processing pipeline, a custom JFR event with live streaming, an AOT cache that took startup from 148 ms down to 98 ms, and a stateless token service built on HKDF-SHA256.
The last section is a summary cheat sheet plus a look at what's coming in Java 26 and beyond.

Who this course is for

⭐ Java developers upgrading from Java 17 or Java 21 who need to know exactly what changed - Backend and microservice developers who care about startup time, memory footprint, and tail latency
⭐ Engineers responsible for profiling and diagnosing applications in production
⭐ Team leads evaluating whether Java 25 is worth the migration effort
⭐ Anyone who has read the JEP list and wants to see the features running instead of described
⭐ It's not an introduction to Java. If you're still learning the language basics, start elsewhere and come back once you're comfortable with generics, lambdas, and streams.

Homepage

https://www.udemy.com/course/java-25-essentials-master-every-new-feature

Rapidgator
qtfjq.Java.25.Essentials.Master.Every.New.Feature.part1.rar.html
qtfjq.Java.25.Essentials.Master.Every.New.Feature.part2.rar.html
qtfjq.Java.25.Essentials.Master.Every.New.Feature.part3.rar.html
qtfjq.Java.25.Essentials.Master.Every.New.Feature.part4.rar.html
qtfjq.Java.25.Essentials.Master.Every.New.Feature.part5.rar.html
AlfaFile
qtfjq.Java.25.Essentials.Master.Every.New.Feature.part1.rar
qtfjq.Java.25.Essentials.Master.Every.New.Feature.part2.rar
qtfjq.Java.25.Essentials.Master.Every.New.Feature.part3.rar
qtfjq.Java.25.Essentials.Master.Every.New.Feature.part4.rar
qtfjq.Java.25.Essentials.Master.Every.New.Feature.part5.rar