list of characters that need escaping

Hi,
I'm trying to construct a list of characters that must be escaped when appearing in a literal in Pig so that they appear correctly when passed to a java UDF.

As examples, here are 2 places where I need to add escapes to get what I want in the udf.
'\$' parses to $
'\\' parses to '\'

I've looked through the parsing code but haven't found an authoritative list. If anyone can point me in the right direction I'd appreciate it.

Thanks!
Adam