Any Java application can be run only inside some concrete implementation of the abstract specification of the Java virtual machine. The main reason for this omission is to not unnecessarily constrain implementers. The garbage collection algorithm used and any internal optimization of the Java virtual machine instructions (their translation into machine code) are not specified. It is a part of java runtime environment.

The Java virtual machine is an abstract (virtual) computer defined by a specification. Eclipse OpenJ9 is another open source JVM for OpenJDK. The commercially supported Java releases available from Oracle are based on the OpenJDK runtime. The JVM reference implementation is developed by the OpenJDK project as open source code and includes a JIT compiler called HotSpot. Having a specification ensures interoperability of Java programs across different implementations so that program authors using the Java Development Kit (JDK) need not worry about idiosyncrasies of the underlying hardware platform. The JVM is detailed by a specification that formally describes what is required in a JVM implementation. Overview of a Java virtual machine (JVM) architecture based on The Java Virtual Machine Specification Java SE 7 EditionĪ Java virtual machine ( JVM) is a virtual machine that enables a computer to run Java programs as well as programs written in other languages that are also compiled to Java bytecode.

Open office java runtime environment