Question

The following article http://docs.oracle.com/javaee/1.4/tutorial/doc/JAXPXSLT3.html says that XPATH considers the following to be nodes:

• Root
• Element
• Text
• Attribute
• Comment
• Processing instruction
• Namespace

What I want to know is whether an attribute ‘id’ and its value ‘2’ are considered to be two different nodes? e.g. <name id="2">text</name>

Or are text nodes just the ‘data’ http://www.w3.org/XML/Datamodel.html between elements? My intuition tells me that XPATH would consider there to be 4 nodes in this example – the ‘name’ element, the attribute ‘id’ the text value ‘2’ and the text value ‘text’.

Answer 1

An attribute node has a name and a value. They are not separate nodes. The following XML:

<name id="2">text</name>

…represents three nodes: 1) an element whose name is name; 2) a child node of name that is a text node; 3) an attribute node whose name is id and whose value is 2.

From the spec:

An attribute node has an expanded-name and a string-value.

And later:

An attribute node has a string-value. The string-value is the
normalized value as specified by the XML Recommendation [XML]. An
attribute whose normalized value is a zero-length string is not
treated specially: it results in an attribute node whose string-value
is a zero-length string.