Here you can find the source of isHexStringChar(char c)
public static final boolean isHexStringChar(char c)
//package com.java2s; public class Main { public static final boolean isHexStringChar(char c) { return (Character.isDigit(c) || Character.isWhitespace(c) || (("0123456789abcdefABCDEF" .indexOf(c)) >= 0));/*from w w w .ja v a 2 s.c om*/ } }