That would mean that your XML document contains an ampersand which hasn't been escaped properly. In particular the error message says that it's
&L and it suggests that you might have meant to use an entity from the DTD, namely
&L;.
But more likely you just produced malformed XML and should have had
&L.
It looks like you're producing XML by
string concatenation. So if you are inserting a text node into XML that way, make sure you escape characters which could be markup characters correctly. Those include
& and
< and
>. Or alternatively, generate your XML with some standard API which knows how to work with XML.