[JENA-1566] Unable to parse VALUES clause containing boolean literal bindings

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: Jena 3.7.0, Jena 3.8.0
• Fix Version/s: Jena 3.9.0
• Component/s: ARQ
• Assignee: Rob Vesse
• Reporter: Lee Kitching
• Created: 27/Jun/18 09:43
• Updated: 08/Oct/18 20:29
• Resolved: 28/Jun/18 08:46

Description

Compiling the query

 

SELECT ?b WHERE { VALUES ?b

{ true }

}

into a query algebra:

Query q = QueryFactory.create("SELECT ?b WHERE { VALUES ?b { true }}");
Op a = Algebra.compile(q);

 

results in

(project
  (?b)
  (table
    (vars ?b)
    (row
      (?b true))))

 

Attempting to parse this string representation throws an exception:

SSE.parseOp("(project (?b) (table (vars ?b) (row (?b true))))");

    org.apache.jena.sparql.sse.builders.ExprBuildException "Not a node: true"

    [org.apache.jena.sparql.sse.builders.BuilderLib exception "BuilderLib.java" 140]
    [org.apache.jena.sparql.sse.builders.BuilderLib broken "BuilderLib.java" 147]
    [org.apache.jena.sparql.sse.builders.BuilderLib broken "BuilderLib.java" 129]
    [org.apache.jena.sparql.sse.builders.BuilderLib checkNode "BuilderLib.java" 32]
    [org.apache.jena.sparql.sse.builders.BuilderBinding buildBinding "BuilderBinding.java" 64]
    [org.apache.jena.sparql.sse.builders.BuilderBinding build "BuilderBinding.java" 36]
    [org.apache.jena.sparql.sse.builders.BuilderTable build "BuilderTable.java" 73]
    [org.apache.jena.sparql.sse.builders.BuilderOp$1 make "BuilderOp.java" 209]
    [org.apache.jena.sparql.sse.builders.BuilderOp build "BuilderOp.java" 128]
    [org.apache.jena.sparql.sse.builders.BuilderOp build "BuilderOp.java" 162]
    [org.apache.jena.sparql.sse.builders.BuilderOp$26 make "BuilderOp.java" 672]
    [org.apache.jena.sparql.sse.builders.BuilderOp build "BuilderOp.java" 128]
    [org.apache.jena.sparql.sse.builders.BuilderOp build "BuilderOp.java" 59]
    [org.apache.jena.sparql.algebra.Algebra parse "Algebra.java" 121]
    [org.apache.jena.sparql.algebra.Algebra parse "Algebra.java" 109]
    [org.apache.jena.sparql.sse.SSE parseOp "SSE.java" 287]

As a bit of background, we are trying to rewrite SPARQL queries using ARQ in Clojure (as described in JENA-1468). The current process is:

Parse SPARQL query -> Compile to Op -> serialise to string -> parse as SSE -> modify SSE -> serialise to string -> Parse to Op -> convert to SPARQL query

This issue is causing the 'parse as SSE' step to fail.

Issue Links

• links to: GitHub Pull Request #440