[JENA-976] Provide machinery for syntax manipulation

• Type: Improvement
• Status: Closed
• Priority: Major
• Resolution: Done
• Fix Version/s: Jena 3.0.0
• Component/s: ARQ
• Assignee: Andy Seaborne
• Reporter: Andy Seaborne
• Created: 26/Jun/15 09:38
• Updated: 29/Jul/15 14:52
• Resolved: 28/Jun/15 20:51

Description

Jena ARQ does a lot of algebra manipulation (for example, the high level optimizer is a collection of algebra transformation rules).

Sometimes, manipulation of query syntax is needed. Examples include rewriting a query with a specific variable replaced by a constant term, or simplying syntax after applying OpAsQuery (for safety, it adds some additonal "{ }" around query parts and these can only be removed in-context; that means a pass over a built query to detect and improve the syntax tree.

This task is to add a framework for query syntax manipulation.