Using a local variable in regex portion of replaceAll(regex, replacement)

Question

While this works..
output = output.replaceAll("(HED>|AUT>)(.*)(</\\1)", "$1<![CDATA[$2]]>$3");
I'd like the list of alternation values to be contained in a variable, for example:
String nodeLIst = "HED>|AUT>";
output = output.replaceAll("(nodeList)(.*)(</\\1)", "$1<![CDATA[$2]]>$3");
The extension of this would be so I can store this stuff in a db as a list and avoid compilation on change, but please don't let this muddy the waters... :)
Any pointers are much appreciated. Links to specific reading material, etc. I've scoured Friedl's Mastering Regular Expressions to no avail. This approach is supported by some other regex engines I've used (perl, php, ORO?) but I'm new to Java.
TIA,
Mark

Answer 1

I've scoured Friedl's Mastering Regular Expressions to no avail.Did you look on page 209? In the book, that code sample is labelled "Building Up a Regex Through Variables in Java". That should have been a clue. ^_^
But seriously, you're probably thinking of the interpolated strings you find in scripting languages like Perl, PHP, Ruby, etc.. But that's a feature of the language itself, not the regex engine, and Java doesn't work that way. (The $1, $2, etc., in the replacement string are processed by the Matcher class, in a very limited imitation of Perl's variable interpolation).
However, you can fake it pretty well with String's format() method:   String regex = String.format("(%s)(.*)(</\\1)", theAlternation);
  output = output.replaceAll(regex, "$1<![CDATA[$2]]>$3"); That way, you can easily escape the dynamic part, in case it might contain regex metacharacters:   String regex = String.format("(%s)(.*)(</\\1)", Pattern.quote(theAlternation));