Java Runtime Environment

Java is a popular programming language used for building a variety of applications. It requires a Java Runtime Environment (JRE) to run. The JRE includes the Java Virtual Machine (JVM), class libraries, and other necessary components.

Java Version

To check the version of Java installed on your system, run the following command in the terminal:

java -version

This command will display the version of Java installed on your system. For example:

java version "1.8.0_311"
Java(TM) SE Runtime Environment (build 1.8.0_311-b11)
Java HotSpot(TM) Client VM (build 25.311-b11, mixed mode, sharing)

In this example, the version of Java installed is 1.8.0_311.

Java Virtual Machine

The Java Virtual Machine (JVM) is responsible for executing Java code. It translates Java bytecode into machine code that can be run by the operating system. The JVM is platform-independent, meaning that the same bytecode can be run on any platform that has a compatible JVM.

Java Class Libraries

Java includes a set of class libraries that provide fundamental functionality for building applications. These libraries contain pre-written code for tasks such as input/output, networking, and error handling. They help simplify the development process by providing commonly used functionality that developers can re-use in their applications.

Java Development Kit

In order to develop Java applications, you will need to install the Java Development Kit (JDK), which includes the JRE as well as other tools such as a compiler, debugger, and documentation. The JDK is available for download from the Java website.

Conclusion

Java is a popular programming language used for building a variety of applications. It requires a Java Runtime Environment (JRE) to run, which includes the Java Virtual Machine (JVM), class libraries, and other necessary components. With the JDK, developers can create Java applications with ease.