Java 17 is out and it includes a host of improvements and new features. Along with these new features, the Oracle JDK will be provided under a free-to-use license that will extend a full year after the next Long Term Support release is available in 2023.

The latest iteration of Java includes new language enhancements, updates to libraries, support for the new Apple M1 hardware, deprecates legacy features, and helps future-proof code.

One of the most important additions to Java is Sealed Classes, which restricts which other classes may extend or implement a class. Sealed Classes will provide additional modularization, can be used to develop internal classes, and can help secure hierarchies by decoupling accessibility from extensibility.

Next in line of importance might be the context-specific decentralized filters, which allow applications to configure context-specific and dynamically selected decentralized filters by way of the JVM-wide filter factory. According to Oracle, deserializing untrusted data is inherently dangerous because the content of the data streams determines the objects created, the values in their files, and all references between them. Find out more about this feature in this JEPS entry.

Other updates and improvements include the restored Always-Strict Floating-Point Semantics, enhanced Pseudo-Random Number Generator, a new macOS rendering pipeline, and strongly encapsulated JDK internals.

Deprecations in Java 17 include the Applet API, RMI Activation, Experimental AOT and JIT compiler, and the Security Manager.

Read the entire JDK 17 release notes for more information.