To run each example use: java --enable-preview --source 20 <FileName.java>

• Record patterns (second preview)
  • added support for inference of type arguments of generic record patterns;
    • now it generic type can be inferred
    • given record Decorator<T>(T t) {} and variable Decorator<Decorator<String>> wr, thee record pattern generic type can be inferred in w insteaceof Decorator(Decorator(var s))
  • added support for record patterns to appear in the headere of an enhanced for statement;
    • for (Point(var x, var y) : shapePoints)
  • remove support for named record pattner.
• Patteren matching for switch (fourth preview)
  • added support for inference of type arguments for generic record patterns
• Virtual threads (second preview)
  • small numbeer of API changes described by JEP 425 were made permanent in JDK 19 and are not proporsed to preview:
    • Thread.join(Durantion)
    • Thread.sleep(Duration)
    • Thread.threadId()
    • Future.resultNow()
    • Future.exceptionNow()
    • Future.state()
    • ExecutorSerevice extends AutoClosable

JEPs proposed to target:

• 429 - Scoped Values (Incubator)
• 432 - Record Patterns (Second Preview)
• 433 - Pattern Matching for switch (Fourth Preview)
• 434 - Foreign Function & Memory API (Second Preview)
• 436 - Virtual Threads (Second Preview)
• 437 - Structured Concurrency (Second Incubator)

• JDK 20 Jeps
• JEP Dashboard
• JDK 20 EA Builds