Question

How to put a supplementary Unicode character (say, codepoint 10400) in a string literal?
I have tried putting a surrogate pair like this:

String text = "TEST \uD801\uDC00";
System.out.println(text);

but it doesn’t seem to work.

UPDATE:

The good news is, the string is constructed properly.
Byte array in UTF-8: 54 45 53 54 20 f0 90 90 80
Byte array in UTF-16: fe ff 0 54 0 45 0 53 0 54 0 20 d8 1 dc 0

But the bad news is, it is not printed properly (in my Fedora box) and I can see a square instead of the expected symbol (my console didn’t support unicode properly).

Answer 1

“Works for me”, what exactly is the issue?

public static void main (String[] args) throws Exception {
    int cp = 0x10400;
    String text = "test \uD801\uDC00";
    System.out.println("cp:    " + cp);
    System.out.println("found: " + text.codePointAt(5));
    System.out.println("len:   " + text.length());
}

Output:

cp:    66560
found: 66560
len:   7

Note that length — like most String methods — deals with chars, not Unicode characters. So much for awesome Unicode support 🙂

Happy coding.