code: private static int scanTypeVariableSignature(String string, int start) {
  		// need a minimum 3 chars "Tx;"
  		if (start >= string.length() - 2) {
  			throw new IllegalArgumentException();
  		}
  		// must start in "T"
  		char c = string.charAt(start);
  		if (c != C_TYPE_VARIABLE) {
  			throw new IllegalArgumentException();
  		}
  		int id = scanIdentifier(string, start + 1);
  		c = string.charAt(id + 1);
  		if (c == C_SEMICOLON) {
  			return id + 1;
  		} else {
  			throw new IllegalArgumentException();
  		}
  	}
docs: Scans the given string for a type variable signature starting at the given
  index and returns the index of the last character.
  <pre>
  TypeVariableSignature:
  <b>T</b> Identifier <b>;</b>
  </pre>
  
  @param string the signature string
  @param start the 0-based character index of the first character
  @return the 0-based character index of the last character
  @exception IllegalArgumentException if this is not a type variable signature