What is the java equivalent to javascript's String.fromCharCode?

Question

What it the java equivalent of javascript's:

String.fromCharCode(n1, n2, ..., nX)

http://www.w3schools.com/jsref/jsref_fromCharCode.asp

Answer 1

new String(new char[]{n1, n2, ..., nX}) works, if I understand what you're asking.

Answer 2

That would be something like as follows:

public static String fromCharCode(int... codePoints) {
    StringBuilder builder = new StringBuilder(codePoints.length);
    for (int codePoint : codePoints) {
        builder.append(Character.toChars(codePoint));
    }
    return builder.toString();
}

Note that casting to char isn't guaranteed to work because the codepoint value might exceed the upper limit of char (65535). The char was established in the dark Java ages when Unicode 3.1 wasn't out yet which goes beyond 65535 characters.

Update: the String has actually a constructor taking an int[] (introduced since Java 1.5, didn't knew it from top of head), which handles this issue correctly. The above could be simplified as follows:

public static String fromCharCode(int... codePoints) {
    return new String(codePoints, 0, codePoints.length);
}