What is the difference between java *.java and java *.class

Hello Here is very simple code and I'm curious about the difference between 'java Main.java and Main.class

class Main {
    public static void main(String[] args) {
        System.out.println("Hello, World");
    }
}

when I compile the Main.java source it creates the Main.class and then I know the proccess of the JVM Work but I just got to know That I can execute Main source without compiling

and it takes a little bit more time when I execute java Main.java

so why it doesn't create Main.class when I execute java Main.java and how it is possible to execute without creating Main.class file?

I expected no Result and error occurs but not..

The .java files are source files, whereas .class files are the bytecode generated by javac - the Java Compiler.

By doing

javac HelloWorld.java

The compiler generates the bytecode.

In general, you do not run the .java files without compiling it. If you're running the project from a IDE, the IDE is probably compiling your code and then executing it. It's a two-step process where the code gets compiled and then executed. You do not see the .class compiled files if they were generated by the IDE, because they're typically located in a temporary hidden directory and not in the project directory.

When you execute the command "java Main.java" in the terminal, it attempts to directly run the Java source file without explicitly compiling it first. The Java Virtual Machine (JVM) responsible for executing Java programs can understand and interpret Java source code directly in certain cases.

However, in most cases, the JVM expects the Java source code to be compiled into bytecode before execution. The bytecode is stored in a separate file with a ".class" extension, such as "Main.class". This bytecode file is generated by the Java compiler (javac) when you compile the Java source code using the command "javac Main.java".

So, when you execute "java Main.java" without explicitly compiling it, the JVM tries to interpret the source code directly, but it may not always be successful or produce the expected results. It's generally recommended to compile the Java source code using "javac" to generate the bytecode file and then use "java" to execute the bytecode (e.g., "java Main").

In your case, since you're experiencing a delay when executing "java Main.java" instead of "java Main", it's possible that the JVM is attempting to dynamically compile the source code at runtime, which adds some overhead and additional time for the execution process. However, this behavior may vary depending on the Java implementation and version you're using.