XML Response file not parsing

We faced big issue on UAT days due to hidden error caused by XMLPARSER

    response_parser := xmlparser.newparser;
    xmlparser.parseclob(response_parser, response_clob);
    resp_dom_doc := xmlparser.getdocument(response_parser);

This caused SOAP UI response XML parsing error and aborting
supportable search , presenting incomplete results.

Exception: ORA-31011: XML parsing failed ORA-19202: Error
occurred
in
XML processing LPX-00217: invalid character 26 (U+001A) Error at
line 1 Stack: ORA-06512: at "XDB.DBMS_XMLPARSER", line 191
ORA-06512: at "APPS.XXRH_SUPX_USER_SVC_PKG", line 759

After lot of search on net and Oracle SR, I found below simple solution to replace control characters from XML clob

pout_response_clob:= regexp_replace(pout_response_clob, '['||chr(1)||'-'||chr(13)||chr(14)||'-'||chr(31)||chr(127)||']','');

What this does is replaces all the control chars and gives back clob which can be parsed by XMLPARSER

More details - https://forums.oracle.com/forums/thread.jspa?messageID=10265001

There are other related functions like DBMS_XMLGEN.CONVERT , DBMS_LOB.CONVERTCLOB etc 

This finding helped us to save big go-live!!!

"Dhundane pe khuda bhi milta hain! "