append
Appends the string representation of the codePoint argument to this sequence.
The argument is appended to the contents of this sequence. The length of this sequence increases by Character.charCount(codePoint).
The overall effect is exactly as if the argument were converted to a char array by the method toChars and the character in that array were then appended to this character sequence.
Return
a reference to this object.
Parameters
code
a Unicode code point
Throws
if the specified codePoint isn't a valid Unicode code point