Definitive Guide To Java 16

Java 16 is released with several finalized and preview features. Records and type pattern matching (instanceof) are now finalized, while sealed classes enter their second preview. The Stream API gains mapMulti and toList methods, the HTTP/2 API gets new builder and BodyPublisher methods, and Unix domain socket support is added for SocketChannel. Project Panama contributes incubating Foreign Linker, Foreign-Memory Access, and Vector APIs. Tooling improvements include remote JFR streaming over JMX and the finalized jpackage packaging tool. Performance improvements span Hotspot metaspace, G1, Parallel GC, ZGC, and Shenandoah. Two important breaking changes: primitive wrapper constructors are deprecated for removal, and JDK internals are now strongly encapsulated by default (illegal access denied).