[AXIOM-374] Behavior of OMFactory#createOMElement(QName [, OMContainer]) is inconsistent between LLOM and DOOM

• Type: Bug
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Affects Version/s: 1.2.12
• Component/s: DOOM
• Assignee: Andreas Veithen
• Reporter: Andreas Veithen
• Created: 21/Jul/11 20:24
• Updated: 20/Feb/16 15:52

Description

The createOMElement(String, OMNamespace), createOMElement(String, OMNamespace, OMContainer) and createOMElement(String, String, String) methods support auto-generating a namespace prefix (by passing a null prefix) and creating an element in the default namespace (by passing an empty string as prefix). This choice doesn't exist for the createOMElement(QName) and createOMElement(QName, OMContainer) methods because the prefix in a QName object can never be null. There is an inconsistency in the behavior of LLOM and DOOM when an empty prefix is passed in the QName object. LLOM will auto-generate a prefix, while DOOM will create an element in the default namespace.

In the case of DOOM, this appears to be a bug because the corresponding createOMElement method contains the following condition:

qname.getPrefix() != null

However, the return value of QName#getPrefix() is never null, and the code that would auto-generate a prefix is unreachable.

On the other hand, the desired behavior depends on the use case, and there are situations where one would like to create an element in the default namespace if the prefix in the QName is an empty string.

Proposed solution:

1. Make sure that DOOM has the same behavior as LLOM, i.e. auto-generate a prefix if QName#getPrefix() returns an empty string.
2. Add additional methods to OMFactory that create an element from a QName, but that allow to specify the intended behavior.