private static char[] getReplacementChars(char ch) {
		char[] replacement = null;
		if (ch == '"') {
			replacement = QUOT_CHARS;
		} else if (ch == '\\') {
			replacement = BS_CHARS;
		} else if (ch == '\n') {
			replacement = LF_CHARS;
		} else if (ch == '\r') {
			replacement = CR_CHARS;
		} else if (ch == '\t') {
			replacement = TAB_CHARS;
		} else if (ch == '\u2028') {
			replacement = UNICODE_2028_CHARS;
		} else if (ch == '\u2029') {
			replacement = UNICODE_2029_CHARS;
		} else if (ch >= CONTROL_CHARACTERS_START && ch <= CONTROL_CHARACTERS_END) {
			replacement = new char[]{'\\', 'u', '0', '0', '0', '0'};
			replacement[4] = HEX_DIGITS[ch >> 4 & 0x000f];
			replacement[5] = HEX_DIGITS[ch & 0x000f];
		}
		return replacement;
	}