java - How to check if string is a valid XML element name?

Question

do you know function in java that will validate a string to be a good XML element name.

Form w3schools:

XML elements must follow these naming rules:

1. Names can contain letters, numbers, and other characters
2. Names cannot start with a number or punctuation character
3. Names cannot start with the letters xml (or XML, or Xml, etc)
4. Names cannot contain spaces

I found other questions that offered regex solutions, isn't there a function that already does that?

Answer 1

Using the org.apache.xerces utilities is a good way to go; however, if you need to stick to Java code that's part of the standard Java API then the following code will do it:

public void parse(String xml) throws Exception {

    XMLReader parser = XMLReaderFactory.createXMLReader();
    parser.setContentHandler(new DefaultHandler());
    InputSource source = new InputSource(new ByteArrayInputStream(xml.getBytes()));
    parser.parse(source);
}

Answer 2

If you are using Xerces XML parser, you can use the XMLChar (or XML11Char) class isValidName() method, like this:

org.apache.xerces.util.XMLChar.isValidName(String name)

There is also sample code available here for isValidName.