Why can't I validate a JComponent?

Question

From JavaDoc:

public void validate()

Validates this container and all of its subcomponents. Validating a container means laying out its s

Answer 1

In the docs for isValid() it says:

A component is valid when it is correctly sized and positioned within its parent container and all its children are also valid.

This is the case until you reach a Top-Level Container (JFrame, JInternalFrame or JApplet). In the example you have in your question, your JComponent doesn't have a parent so it can never be valid.