What does this regex means? [closed]

Question

I find this java regex, but don't understand what does it match?

Pattern.compile("\\p{javaJavaIdentifierStart}\\p{javaJavaIdentifierPart}*(\\.\\p{javaJavaIdentifierStart}\\p{javaJavaIdentifierPart}*)*");

What javaJavaIdentifierStart matches?

Answer 1

\\p{javaJavaIdentifierStart} means a character acceptable to be the first character of any valid java identifier.

\\p{javaJavaIdentifierStart}\\p{javaJavaIdentifierPart}*\\.\\p{javaJavaIdentifierStart}\\p{javaJavaIdentifierPart}* means anyIdentifier.anyIdentifier - two java identifiers, separated by dot (namespace name and class name, class name and static member name, object name and member name or etc.)

Full (corrected) regex means (maybe qualified) java identifier - simple "name" or a chain of "names", separated by dots. It is not neccessary for it to be a fully qualified name though.