JDK 10 Release Date, Download Links, and Major New Features

JDK 10, the standard edition of Java 10, was released on March 20 2018 as part of Oracle's six‑month release cadence. To download the early‑access build, users must join the Early‑Access program and can obtain the binaries from the official OpenJDK and Oracle JDK URLs.

The major features of JDK 10 include:

Local‑variable type inference using the new var keyword, reducing boilerplate in variable declarations.

A clean garbage‑collector (GC) interface that improves modularity of HotSpot GC code.

An enhanced G1 GC with parallel execution to lower worst‑case latency.

Support for allocating the Java heap on alternative memory devices such as NVDIMM.

Experimental Java‑based JIT compiler support on Linux /x64.

Consolidation of multiple JDK repositories into a single source tree, simplifying development and source‑code management.

Application data sharing via cross‑process class metadata sharing.

Thread‑local handshakes that allow callbacks without a global VM safepoint.

Provision of default certificates for the open‑source Java SE CA.

Two target releases are highlighted:

Local‑variable type inference, which eliminates the need for explicit type declarations in many cases.

Integration of the JDK libraries into a single source tree.

Example of traditional Java variable declaration:

MyObject value = new MyObject();

With the new var keyword, the same code becomes:

var value = new MyObject();

And a generic list can be written as:

var list = new ArrayList
();

The var keyword is context‑sensitive; it may be used for variables, methods, or packages without affecting existing code, but cannot be used as a class or interface name. Type inference is limited to local variable initializers, enhanced‑for loop indices, and traditional for‑loop declarations, and does not apply to method signatures, fields, or other contexts.

JDK 10 also proposes merging the eight existing Mercurial repositories (root, corba, hotspot, jaxp, jaxws, JDK, langtools, nashorn) into a single repository, improving traceability of bug fixes and simplifying mirroring to Git.

Suggested releases beyond the target features include:

Cleaning up the GC interface (JEP 304) to make it easier to add new collectors and maintain existing ones.

Parallelizing the G1 GC (JEP 307) to match the performance characteristics of the Parallel Collector.

Introducing a thread‑local handshake (JEP 312) to allow stopping individual threads without a global safepoint, albeit with some performance trade‑offs.

In conclusion, JDK 10 continues the evolution begun with JDK 9, introducing type inference, repository consolidation, and several GC and threading enhancements that represent a significant milestone in the Java platform roadmap.