Java Runtime Environment Definition & Meaning

Java Runtime Environment (JRE) is a software layer that runs on top of a computer’s operating system, providing additional services that a specific Java program needs to run. JRE is one of three interrelated components that form a trifecta for developing and running Java applications. The other two are:

JRE combines Java code created using the JDK with the libraries required to run it on a JVM. Then, an instance is created of the JVM that executes the resulting program.

JRE provides many integration libraries such as Java IDL, Java Database Connectivity, and Java Naming and Directory Interface to help developers create seamless data connections between applications and services. JRE also includes packages that are foundational for the design of applications. Some packages include collections framework, concurrency utilities, preferences API, and Java Archive.

How the Java Runtime Environment works

To create a runtime environment, JDK and JRE interact to enable a smooth execution of Java-based applications within any operation system. The following processes take place at runtime:

ClassLoader

The Java ClassLoader dynamically loads all necessary classes needed to run a Java program. It provides security by separating namespaces of the local file system from what’s imported through the network. Since Java classes are only loaded into memory when it’s required, the JRE uses ClassLoader to process this demand.

Bytecode verifier

The bytecode verifier ensures the format and accuracy of Java code before it’s passed to the interpreter. It also checks for illegal code, which is code that violates access rights on objects or violates the implementation of pointers. If a code is in violation, the class will be considered corrupted and will not be loaded.

Interpreter

After the bytecode is successfully verified, at runtime it is loaded, checked, and run by the interpreter. The interpreter creates an instance of the JVM that allows the program to be executed natively on the underlying hardware.






Abby Dykes
Abby Dykes
Abby Dykes is a newly-graduated writer and editor for websites such as TechnologyAdvice.com, Webopedia.com, and Project-Management.com. When she’s not writing about technology, she enjoys giving too many treats to her dog and coaching part-time at her local gym.

Top Articles

Huge List Of Texting and Online Chat Abbreviations

From A3 to ZZZ we list 1,559 text message and online chat abbreviations to help you translate and understand today's texting lingo. Includes Top...

How To Create A Desktop Shortcut To A Website

This Webopedia guide will show you how to create a desktop shortcut to a website using Firefox, Chrome or Internet Explorer (IE). Creating a desktop...

The History Of Windows Operating Systems

Microsoft Windows is a family of operating systems. We look at the history of Microsoft's Windows operating systems (Windows OS) from 1985 to present...

Hotmail [Outlook] Email Accounts

  By Vangie Beal Hotmail is one of the first public webmail services that can be accessed from any web browser. Prior to Hotmail and its...

Unregulated Power Supply Definition...

An unregulated power supply is a system that transforms input voltage into direct...

Cybersecurity Awareness Training Definition...

Cybersecurity awareness training informs employees of the attack surfaces and vectors in their...

OST File Definition &...

An OST file, or offline storage table (.ost) file, is an Offline Outlook...