Features :

339: Edwards-Curve Digital Signature Algorithm (EdDSA)

360: Sealed Classes (Preview)

371: Hidden Classes

372: Remove the Nashorn JavaScript Engine

373: Reimplement the Legacy DatagramSocket API

374: Disable and Deprecate Biased Locking

375: Pattern Matching for instanceof (Second Preview)

377: ZGC: A Scalable Low-Latency Garbage Collector

378: Text Blocks

379: Shenandoah: A Low-Pause-Time Garbage Collector

381: Remove the Solaris and SPARC Ports

383: Foreign-Memory Access API (Second Incubator)

384: Records (Second Preview)

385: Deprecate RMI Activation for Removal

Resource : https://openjdk.java.net/projects/jdk/15/