Using Java XML to check for valid XML elements

	public static void main(String[] args) 
	{	
		 matchesElementTags( "hello" );
		 matchesElementTags( "<hello>" );
		 matchesElementTags( "hello>" );
		 matchesElementTags( "<hello" );
 
		 matchesElementTags( "<HellO>" );
		 matchesElementTags( "<hello123>" );
		 matchesElementTags( "<123hello>" );
		 matchesElementTags( "<123hello123>" );
 
		 matchesElementTags( "<hello>abc</hello>" );
 
 
		 matchesXmlHeader( XML_HEADER );
		 matchesXmlHeader( XML_HEADER + "blah blah" );
	}
 
	private static void matchesElementTags( String stg )
	{
		String startingElementPattern = "\\<([a-z]|[A-Z]|[0-9])++\\>";
		String endingElementPattern = "\\</([a-z]|[A-Z]|[0-9])++\\>";
		String anyCharacter = "([a-z]|[A-Z]|[0-9])++";
		System.out.println("matches element: " + Pattern.matches( startingElementPattern + anyCharacter + endingElementPattern, stg ) );
	}
 
	private static void matchesXmlHeader( String stg )
	{
		String xmlHeaderPattern = "\\<\\?xml.*\\?\\>.*";
		System.out.println("matches header: " + Pattern.matches( xmlHeaderPattern, stg ) );
	}
 
	private static final String XML_HEADER = "<?xml version='1.0' encoding='UTF-8'?>";