What happens when you run a Java Program?

Let suppose you run a Hello World program!
HelloWorld.java

public class HelloWorld(){
    public static void main(String[] args){
       System.out.println("Hello World!");
    }
}
 Compile Time :

Java Code(.java files) -------Compiler-------> Byte Code(.class files)


Before JVM(Java Virtual Machine) runs the program,the program needed to be converted to Byte-Code, which is platform independent.Compiler compiles and generates .class files if the program is error free.These class files are saved in Workspace/classpath specified

 Run Time :

Byte Code(.class files) -----Interpreter----->Executes the instructions


Now, JVM is invoked to run the byte-code.It searches for the .class file in the path/workspace and executes it.
In detail, JVM
>Classloader loads the compiled (.class files)  code,
>ByteCode Verifier verifies the bytecode ,
>Then interpreter comes into picture where it takes over the control of bytecode and converts it to machine readable instructions and executes them.




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