This article provides non-exhaustive lists of Java SE Java virtual machines (JVMs). It does not include a large number of Java ME vendors. Note that Java EE runs on the standard Java SE JVM but that some vendors specialize in providing a modified JVM optimized for Java EE applications. A large amount of Java development work takes place on Windows, Solaris and Linux, primarily with the Sun JVMs. Note the further complication of different 32-bit/64-bit varieties.
The primary reference Java VM implementation is HotSpot, produced by Oracle Corporation.
Proprietary implementations 
- Azul Zing JVM a fully compliant Java Virtual Machine based on HotSpot that uses the Azul C4 (Continuously Concurrent Compacting Collector) garbage collector. Supports memory heaps up to 512 GB without GC pauses and is able to grow and shrink the heap based on load.
- CEE-J is a clean room implementation of Sun's Java technology, Skelmir is not a licensee of Oracle.
- Excelsior JET is a licensed Java SE implementation with AOT compiler
- Hewlett-Packard, Java for HP-UX, OpenVMS, Tru64 and Reliant (Tandem) UNIX platforms
- J9 (IBM), for Windows, AIX, Linux (x86 and PPC), MVS, OS/400, Pocket PC, z/OS
- "Classic JVM" for IBM OS/400 (superseded by J9)
- Imsys AB provides their SNAP (Simple Network Application Platform) JVM running on their proprietary IM1000 and IM3000 microprocessors that feature microcode execution of Java byte codes.
- Apogee provides embedded Java using IBM J9 and Apache Harmony Class Library for X86, ARM, MIPS, PowerPC running on Linux, LynxOS, WinCE.
- JBed, (Esmertec) is an embedded Java with multimedia capabilities
- JamaicaVM, (aicas) is a hard real-time Java VM for embedded systems
- JBlend, (Aplix) is a Java ME implementation
- JRockit (originally from Appeal Virtual Machines) acquired by Oracle for Linux, Windows and Solaris
- Mac OS Runtime for Java (MRJ)
- MicroJvm (IS2T - Industrial Smart Software Technology) Wide range of virtual machines dedicated to embedded systems (including hard real-time constrained systems), ARM7, ARM9, AVR, AVR32, PPC, MIPS, ...
- Microsoft Java Virtual Machine (discontinued in 2001)
- OJVM (also known as "JServer") from Oracle Corporation
- PERC (Aonix/Atego) is a real time Java for embedded. Aonix is not a licensee of Oracle.
- SAPJVM (SAP) is a licensed and modified SUN JVM ported to all supported platforms of SAP NetWeaver, started as Java 5, in the meantime Java 6 compatible (Windows i386, x64, IA-64; Linux x86, IA-64, PowerPC; AIX PowerPC; HP-UX SPARC IA-64; Solaris SPARC x86-64; i5/OS PowerPC)
- Waratek Cloud VM for Java A multitenant JVM that allows per-tenant isolation, metering and resource control
Lesser-known proprietary Java virtual machines 
Free and open source implementations 
- AegisVM (inactive since 2004).
- Apache Harmony — supports several architectures and systems. Apache License 2.0.
- Avian — A small, easily embeddable Java VM and classpath using just-in-time compilation.
- CACAO — uses GNU Classpath, supports multiple architectures. GPL. 1.6.0 released September 4, 2012.
- Dalvik used in Google Android
- GCJ the GCC Java compiler, that compiles either to bytecode or to native machine code.
- HaikuVM, for Atmel AVRs (Arduino) and other micros using the leJOS runtime.
- HotSpot, the primary reference Java VM implementation.
- IcedTea — has the only working free software Java Web browser plugin. GPL+linking exception.
- IKVM.NET — Java for Mono and the Microsoft .NET Framework. Uses OpenJDK. Zlib License.
- Jamiga — for the Amiga platform. Depends on GNU Classpath. GPL.
- JamVM — Developed to be an extremely small virtual machine compared to others. Designed to use GNU Classpath. Supports several architectures. GPL.
- Jaos — Java on Active Object System. Uses GNU Classpath as a standard library. Unmaintained.
- Jato VM — uses GNU Classpath. GPL.
- JC — Converts class files from byte-code into C. Uses Soot and GNU Classpath. GNU Library or LGPL licenses.
- Jelatine JVM.
- JESSICA (Java-Enabled Single-System-Image Computing Architecture).
- Jikes RVM (Jikes Research Virtual Machine) — Research project. PPC and IA-32. Supports Apache Harmony and GNU Classpath libraries. Eclipse Public License.
- JNode — operating system. Version 0.2.8 released on January 29, 2009. LGPL.
- JOP — Hardware implementation of the JVM. GPL 3.
- Juice — JavaME experimental JVM developed to run on the NUXI operating system.
- Jupiter — Uses Boehm garbage collector and GNU Classpath. GPL. Unmaintained.
- JwiK™ Open Source Java VM for 8bit micro for wireless applications.
- JX (operating system) — GPL. Version 0.1.1 released on October 10, 2007.
- Kaffe — Uses GNU Classpath. GPL. 1.1.9 released on February 26, 2008.
- leDos real-mode x86 JVM running on MS-DOS. MPL.
- leJOS — Robotics suite, a firmware replacement for Lego Mindstorms programmable bricks, provides a Java programming environment for the Lego Mindstorms RCX and NXT robots.
- MateVM — An experimental JIT implemented in Haskell. GPL.
- Maxine — meta-circular open source research VM from Oracle Labs.
- Mika VM — intended for use in embedded devices. Cross-platform. BSD-style licence.
- miniMV (from UABC-Tij for embedded systems and Wireless Sensor network devices).
- Mysaifu (Windows CE/Windows Mobile) — the only open source Java SE-compatible JVM still in development for PocketPC devices. GPL 2.
- NanoVM — developed to run on the Atmel AVR ATmega8 used in the Asuro Robot, can be ported to other AVR-based systems.
- SableVM — First free software JVM to support JVDMI and JDWP. Makes use of GNU Classpath. LGPL. Version 1.13 released on March 30, 2007.
- Squawk virtual machine — A Java ME VM for embedded systems and small devices. Cross-Platform. GPL.
- SuperWaba — Java-like virtual machine for portable devices. GPL. Discontinued, succeeded by TotalCross.
- TakaTuka — for wireless sensor network devices. GPL.
- VM02 a Java-compatible environment for the Apple II series of computers.
- VMkit of Low Level Virtual Machine.
- Wonka VM — Developed to run on Acunia's ARM-based hardware. Some code drawn from GNU Classpath. BSD-style licence. No longer under active development, superseded by Mika VM.
See also 
External links