Java Architecture

Java Architecture is a framework that combines compilation and interpretation to run the Java programs on any device based on WORA principle. The core components are JDK, JVM and JRE.

Java Development Kit (JDK): This is a software package used to develop Java programs. It includes the Java Runtime Environment (JRE), which is needed to run programs, plus tools like the Java compiler that turns your code into bytecode, and other tools for debugging and creating documentation.

Components of JDK:

1. JRE (Java Runtime Environment)
2. Java Compiler (javac) - Converts Java source code (.java) into bytecode (.class).
3. Debugger (jdb) - This helps to find and fix errors in the code. JDK = JRE + Development tools

Java Runtime Environment (JRE): This provides the necessary environment to run Java programs. It includes the Java Virtual Machine (JVM), which executes Java bytecode, and the core class libraries that programs use for standard functions like input/output, networking, and data structures. Unlike the JDK, the JRE does not include development tools like the compiler or debugger, so it is only used for running Java applications, not creating them.

Java Virtual Machine (JVM): The Java Virtual Machine (JVM) is a part of the Java Runtime Environment (JRE) that lets Java programs run on any computer or operating system. It takes the Java bytecode (compiled code) and converts it into machine code that the computer can understand. The JVM also helps manage memory, automatically removes unused objects (garbage collection), and keeps the program safe. It is the main reason Java can run anywhere without changes.