JENA-1563: Accept lang and dt=rdf:langString

charischen · Jun 13, 2018 · 79a04c0 · 79a04c0
1 parent 874ad4e
commit 79a04c0
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Showing 2 changed files with 22 additions and 9 deletions.
diff --git a/jena-arq/src/main/java/org/apache/jena/riot/resultset/rw/ResultSetReaderJSON.java b/jena-arq/src/main/java/org/apache/jena/riot/resultset/rw/ResultSetReaderJSON.java
@@ -51,6 +51,7 @@
 import org.apache.jena.sparql.resultset.ResultSetException;
 import org.apache.jena.sparql.resultset.SPARQLResult;
 import org.apache.jena.sparql.util.Context;
+import org.apache.jena.vocabulary.RDF;
 
 /** Read JSON format SPARQL Results.
  * <p>
@@ -209,8 +210,16 @@ private static Node parseOneTerm(JsonObject term, LabelToNode labelMap) {
             if ( kLiteral.equals(type) || kTypedLiteral.equals(type) ) {
                 String lang = stringOrNull(term, kXmlLang);
                 String dtStr = stringOrNull(term, kDatatype);
-                if ( lang != null && dtStr != null )
-                    throw new ResultSetException("Both language and datatype defined: " + term);
+                if ( lang != null ) {
+                    // Strictly, xml:lang=... and datatype=rdf:langString is wrong (the datatype should be absent)
+                    // The RDF specs recommend omitting the datatype. They did however come after the SPARQL 1.1 docs
+                    // it's more of a "SHOULD" than a "MUST".
+                    // datatype=xsd:string is also unnecessary.
+                    if ( dtStr != null && ! dtStr.equals(RDF.dtLangString.getURI() ) ) {
+                        // Must agree.
+                        throw new ResultSetException("Both language and datatype defined, datatype is not rdf:langString:\n" + term);
+                    }
+                }
                 RDFDatatype dt = TypeMapper.getInstance().getSafeTypeByName(dtStr);
                 return NodeFactory.createLiteral(v, lang, dt);
             }

diff --git a/jena-core/src/main/java/org/apache/jena/datatypes/TypeMapper.java b/jena-core/src/main/java/org/apache/jena/datatypes/TypeMapper.java
@@ -106,14 +106,18 @@ public TypeMapper() {
 
 
     /**
-     * Version of getTypeByName which will treat unknown URIs as typed
-     * literals but with just the default implementation
+     * Version of getTypeByName which will treat unknown URIs as typed literals but with
+     * just the default implementation
+     * <p>
+     * RDF 1.1: null for {@code uri} returns null and it wil mean {@code xsd:string}
+     * because plain literals (no lang tag) and xsd:strings are now the same.
      *
-     * @param uri the URI of the desired datatype
-     * @return Datatype the datatype definition
-     * registered at uri, if there is no such registered type it
-     * returns a new instance of the default datatype implementation, if the
-     * uri is null it returns null (indicating a plain RDF literal).
+     * @param uri
+     *            the URI of the desired datatype
+     * @return Datatype the datatype definition registered at uri, if there is no such
+     *         registered type it returns a new instance of the default datatype
+     *         implementation, if the uri is null it returns null (indicating a plain RDF
+     *         literal).
      */
     public RDFDatatype getSafeTypeByName(final String uri) {
         RDFDatatype dtype = uriToDT.get(uri);