public class SupplementaryCharTest1 {
    public static void main(String[] args) {
        int codePoint = 0x00010400;
        System.out.format("Char U+0010400 = %c\n", codePoint);
        System.out.format("U+0010400 is %s%n", Character.UnicodeBlock.of(codePoint));
    }
}