Java entry point rules: what happens when main is not declared static?\n\npublic class F0091 {\n public void main(String[] args) {\n System.out.println("Hello" + args[0]);\n }\n}\n// Command line: > java F0091 world

Introduction / Context:
The Java Virtual Machine requires a specific entry point signature to launch an application: public static void main(String[] args). If the main method is not static, the JVM will not treat it as an entry point, even if the name “main” and parameter list match.

Given Data / Assumptions:

• The class declares public void main(String[] args) without static.
• Invocation is through the JVM launcher: java F0091 world.
• No other main method exists with the correct signature.

Concept / Approach:
Because the JVM looks specifically for a static method, it cannot call an instance main automatically. The launcher reports a “Main method not found in class F0091” (or similar) and terminates without executing user code.

Step-by-Step Solution:

Verification / Alternative check:
Changing the signature to public static void main(String[] args) compiles and runs; output would be “Hello world”.

Why Other Options Are Wrong:

• Hello / Hello Foo91 / Hello world: All assume the program ran.
• Compilation fails due to println: System.out.println is valid; issue is the missing static modifier.

Common Pitfalls:
Forgetting static, wrong parameter type (e.g., String args), or wrong access modifier prevents the application from starting.

Final Answer:
The code does not run.