Question

In my environment here I use Java to serialize the result set to XML. It happens basically like this:

//foreach column of each row xmlHandler.startElement(uri, lname, 'column', attributes); String chars = rs.getString(i); xmlHandler.characters(chars.toCharArray(), 0, chars.length()); xmlHandler.endElement(uri, lname, 'column'); 

The XML looks like this in Firefox:

<row num='69004'>     <column num='1'>10069</column>     <column num='2'>sd&#26;</column>     <column num='3'>FCVolume                      </column> </row> 

But when I parse the XML I get the a

org.xml.sax.SAXParseException: Character reference ‘&#26‘ is an invalid XML character.

My question now is: Which charactes do I have to replace or how do I have to encode my characters, that they will be valid XML?

Answer 1

I found an interesting list in the Xml Spec: According to that List its discouraged to use the Character #26 (Hex: #x1A).

The characters defined in the following ranges are also discouraged. They are either control characters or permanently undefined Unicode characters

See the complete ranges.

This code replaces all non-valid Xml Utf8 from a String:

public String stripNonValidXMLCharacters(String in) {     StringBuffer out = new StringBuffer(); // Used to hold the output.     char current; // Used to reference the current character.      if (in == null || (''.equals(in))) return ''; // vacancy test.     for (int i = 0; i < in.length(); i++) {         current = in.charAt(i);         if ((current == 0x9) ||             (current == 0xA) ||             (current == 0xD) ||             ((current >= 0x20) && (current <= 0xD7FF)) ||             ((current >= 0xE000) && (current <= 0xFFFD)) ||             ((current >= 0x10000) && (current <= 0x10FFFF)))             out.append(current);     }     return out.toString(); }     

its taken from Invalid XML Characters: when valid UTF8 does not mean valid XML

But with that I had the still UTF-8 compatility issue:

org.xml.sax.SAXParseException: Invalid byte 1 of 1-byte UTF-8 sequence 

After reading XML – returning XML as UTF-8 from a servlet I just tried out what happens if I set the Contenttype like this:

response.setContentType('text/xml;charset=utf-8'); 

And it worked ….