question: public static IntsRef toUTF32 ( CharSequence s , IntsRefBuilder scratch ) { int charIdx = 0 ; int intIdx = 0 ; final int charLimit = s . length ( ) ; while ( charIdx < charLimit ) { scratch . grow ( intIdx + 1 ) ; final int utf32 = Character . codePointAt ( s , charIdx ) ; scratch . setIntAt ( intIdx , utf32 ) ; charIdx += Character . charCount ( utf32 ) ; intIdx ++ ; } scratch . setLength ( intIdx ) ; return scratch . get ( ) ; }
target:  Decodes the Unicode codepoints from the provided CharSequence and places them in the provided scratch IntsRef, which must not be null, returning it. 