common/src/main/java/com/streamsets/pipeline/lib/parser/shaded/com/google/code/regexp/Pattern.java
static private boolean isQuoteEscapedChar(String s, int pos) {

        boolean openQuoteFound = false;
        boolean closeQuoteFound = false;

        // find last non-escaped open-quote
        String s2 = s.substring(0, pos);
        int posOpen = pos;
        while ((posOpen = s2.lastIndexOf("\\Q", posOpen - 1)) != -1) {
            if (!isSlashEscapedChar(s2, posOpen)) {
                openQuoteFound = true;
                break;
            }
        }

        if (openQuoteFound) {
            // search remainder of string (after open-quote) for a close-quote;
            // no need to check that it's slash-escaped because it can't be
            // (the escape character itself is part of the literal when quoted)
            if (s2.indexOf("\\E", posOpen) != -1) {
                closeQuoteFound = true;
            }
        }

        return openQuoteFound && !closeQuoteFound;
    }
static private boolean isQuoteEscapedChar(String s, int pos) {

        boolean openQuoteFound = false;
        boolean closeQuoteFound = false;

        // find last non-escaped open-quote
        String s2 = s.substring(0, pos);
        int posOpen = pos;
        while ((posOpen = s2.lastIndexOf("\\Q", posOpen - 1)) != -1) {
            if (!isSlashEscapedChar(s2, posOpen)) {
                openQuoteFound = true;
                break;
            }
        }

        if (openQuoteFound) {
            // search remainder of string (after open-quote) for a close-quote;
            // no need to check that it's slash-escaped because it can't be
            // (the escape character itself is part of the literal when quoted)
            if (s2.indexOf("\\E", posOpen) != -1) {
                closeQuoteFound = true;
            }
        }

        return openQuoteFound && !closeQuoteFound;
    }
Determines if the character at the specified position
of a string is quote-escaped (between \\Q and \\E)

@param s string to evaluate
@param pos the position of the character to evaluate
@return true if the character is quote-escaped; otherwise false