Java charAt used with characters that have two code units
It sounds like tho book is saying that ‘ℤ’ is not a UTF-16 character in the basic multilingual plane, but in fact it is. Java uses UTF-16 with surrogate pairs for characters that are not in the basic multilingual plane. Since ‘ℤ’ (0x2124) is in the basic multilingual plane it is represented by a single … Read more