Java bytecode is an intermediate code that’s generated by a Java compiler after the source code is compiled.
Byte code is an intermediary code produced by the compiler. This code is generated ater the compilation of JAVA Program (souce code). Byte code is platform independent that means it can be run on any platform with JVM. The WORA (write once, run anywhere) feature is implemented with byte code. WORA is the term given to a program which has an ability to run on all common operating system.
List of Programming Languages which uses Bytecode
Here are some following programming languages that are used by Bytecode-
- PHP
- Raku
- Lisp
- Scala
- Prolog
- Unicon
How Java Bytecode Works?
When you create a Java programme, the compiler first compiles it and creates bytecode for that code. You can use any other platform to run this .class file if we want to. After the initial compilation, the Java Virtual Machine (JVM), rather than the processor under consideration, now executes the resulting bytecode. This effectively means that you only need a minimal installation of Java for whatever platform you want your code to run on. The Java Virtual Machine requests the processor to provide the resources needed to run the bytecode. The processor then responds by allocating the resources as requested. Because JVMs are stack-based, they use implementations that stack to read codes.
- The code that is written in a high level language like Java is called source code. A high-level language is one that is user-friendly for programmers, contains English-language statements, and is similar to human languages. Java files have the “.java” extension.
- When we compile the application a “.java” file which is compiled by the compiler, and a “.class” file is generated as a result. It contains bytecode.
- Bytecode allows to run the “.class” file on any other platform.
- But in order to run this bytecode, you need an interpreter. The JVM works as interpreter here. A JVM interpreter exists. Up until it encounters a mistake or reaches the end of the code, it runs the code piecemeal, or one statement at a time.
Advantages of Bytecode
- Bytecode makes java a platform independent language.
- Bytecode is run only by virtual machine, so it helps java to be a secure programming language.
- Since bytecode typically is smaller than source code, it can be sent via networks like the internet quickly and easily.
- The JVM executes this machine-level language code.