class Main {
    public static void main(String[] args) {
        // I caratteri alle posizioni 4/5, 7/8, 10/11 richiedono surrogate pairs
        String s = "abcd𝒞a𝒮b𝔹asdf";
        System.out.println((int)s.charAt(0)==s.codePointAt(0)); // true, infatti il primo carattere sta in un solo char
        System.out.println((int)s.charAt(4)==s.codePointAt(4)); // false, il carattere alla posizione 4 richiede surrogate pairs
        // esaminiamo da "vicino" un carattere strambo
        System.out.print(s.substring(4,6) + " = codepoint " + Integer.toString(s.codePointAt(4),16));
        System.out.println(" = coppia surrogata " + Integer.toString(s.charAt(4),16) + " - " + Integer.toString(s.charAt(5),16));
    }
}

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