Module org.apache.jena.arq
Package org.apache.jena.sparql.util

Class NodeUtils

java.lang.Object
org.apache.jena.sparql.util.NodeUtils
public class NodeUtils extends Object
Node utilities. See NodeCmp for node comparison operations.

  • Field Summary

    Fields
    Modifier and Type
    Field
    Description
    static EqualityTest
    sameNode
    Both null or same node : Node.equals
    static EqualityTest
    sameRdfTerm
    Term comparison.
    static EqualityTest
    sameValue
    sameValue by SPARQL rules

  • Constructor Summary

    Constructors
    Constructor
    Description
    NodeUtils()
     

  • Method Summary

    Modifier and Type
    Method
    Description
    static org.apache.jena.graph.Node
    asNode(String iri)
    IRI string to Node
    static List<org.apache.jena.graph.Node>
    convertToListNodes(String... namedGraphs)
    Convert strings to a List of Nodes.
    static List<org.apache.jena.graph.Node>
    convertToListNodes(List<String> namedGraphs)
    Convert strings to a List of Nodes.
    static Set<org.apache.jena.graph.Node>
    convertToSetNodes(String... namedGraphs)
    Convert a collection of strings to a set of Nodes.
    static Set<org.apache.jena.graph.Node>
    convertToSetNodes(Collection<String> namedGraphs)
    Convert a collection of strings to a set of Nodes.
    static boolean
    hasLang(org.apache.jena.graph.Node node)
    Return true if the node is a literal and has a language tag.
    static boolean
    hasLangDir(org.apache.jena.graph.Node node)
    Return true if the node is a literal and has an base direction
    static boolean
    isDirLangString(org.apache.jena.graph.Node n)
    A Node is a language string if it has a language tag.
    static boolean
    isLangString(org.apache.jena.graph.Node n)
    A Node is a language string if it has a language tag.
    static boolean
    isSimpleString(org.apache.jena.graph.Node n)
    A Node is a simple string if: (RDF 1.0) No datatype and no language tag (RDF 1.1) xsd:string
    static boolean
    isValidAsRDF(org.apache.jena.graph.Node s, org.apache.jena.graph.Node p, org.apache.jena.graph.Node o)
    Determines whether a triple (as s/p/o) is valid as a RDF statement.
    static boolean
    isValidAsRDF(org.apache.jena.graph.Node g, org.apache.jena.graph.Node s, org.apache.jena.graph.Node p, org.apache.jena.graph.Node o)
    Determines whether a quad (as g/s/p/o) is valid as a RDF statement.
    static boolean
    isXSDNumeric(org.apache.jena.graph.Node node)
    Return true if the node is a literal and has an XSD numeric datatype.
    static Iterator<String>
    nodesToURIs(Iterator<org.apache.jena.graph.Node> iter)
    Convert IRI Nodes to strings.
    static org.apache.jena.graph.Node
    nullToAny(org.apache.jena.graph.Node n)
     
    static StreamRDF
    removeGeneralizedRDF(StreamRDF data)
    Filter out triples and quads that are "generalized" RDF
    static String
    stringLiteral(org.apache.jena.graph.Node literal)
    Get lexical form of anything that looks like a string literal.

    Methods inherited from class java.lang.Object

    equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

  • Field Details

    • sameNode

      public static EqualityTest sameNode
      Both null or same node : Node.equals

    • sameRdfTerm

      public static EqualityTest sameRdfTerm
      Term comparison. Node.equals or lang tags are case insensitive

    • sameValue

      public static EqualityTest sameValue
      sameValue by SPARQL rules

  • Constructor Details

    • NodeUtils

      public NodeUtils()

  • Method Details

    • asNode

      public static org.apache.jena.graph.Node asNode(String iri)
      IRI string to Node

    • hasLang

      public static boolean hasLang(org.apache.jena.graph.Node node)
      Return true if the node is a literal and has a language tag. It may be a rdf:langString or rdf:dirLangString.

    • hasLangDir

      public static boolean hasLangDir(org.apache.jena.graph.Node node)
      Return true if the node is a literal and has an base direction

    • stringLiteral

      public static String stringLiteral(org.apache.jena.graph.Node literal)
      Get lexical form of anything that looks like a string literal. Returns the string value of plain literal (simple literal or lang string) or XSD string.

    • nullToAny

      public static org.apache.jena.graph.Node nullToAny(org.apache.jena.graph.Node n)

    • nodesToURIs

      public static Iterator<String> nodesToURIs(Iterator<org.apache.jena.graph.Node> iter)
      Convert IRI Nodes to strings. Skip other kinds of Node

    • convertToSetNodes

      public static Set<org.apache.jena.graph.Node> convertToSetNodes(Collection<String> namedGraphs)
      Convert a collection of strings to a set of Nodes.

    • convertToSetNodes

      public static Set<org.apache.jena.graph.Node> convertToSetNodes(String... namedGraphs)
      Convert a collection of strings to a set of Nodes.

    • convertToListNodes

      public static List<org.apache.jena.graph.Node> convertToListNodes(String... namedGraphs)
      Convert strings to a List of Nodes.

    • convertToListNodes

      public static List<org.apache.jena.graph.Node> convertToListNodes(List<String> namedGraphs)
      Convert strings to a List of Nodes.

    • isXSDNumeric

      public static boolean isXSDNumeric(org.apache.jena.graph.Node node)
      Return true if the node is a literal and has an XSD numeric datatype.

    • isSimpleString

      public static boolean isSimpleString(org.apache.jena.graph.Node n)
      A Node is a simple string if:
      • (RDF 1.0) No datatype and no language tag
      • (RDF 1.1) xsd:string

    • isLangString

      public static boolean isLangString(org.apache.jena.graph.Node n)
      A Node is a language string if it has a language tag. (RDF 1.0 and RDF 1.1)

    • isDirLangString

      public static boolean isDirLangString(org.apache.jena.graph.Node n)
      A Node is a language string if it has a language tag. (RDF 1.0 and RDF 1.1)

    • isValidAsRDF

      public static boolean isValidAsRDF(org.apache.jena.graph.Node s, org.apache.jena.graph.Node p, org.apache.jena.graph.Node o)
      Determines whether a triple (as s/p/o) is valid as a RDF statement.

      This function reflects the fact that the Triple API is flexible in allowing any Node type in any position (including non-RDF node types like Variable) and as such not all Triples can be safely converted into Statements

      Parameters:
      s - Subject
      p - Predicate
      o - Object
      Returns:
      True if a valid as a statement

    • isValidAsRDF

      public static boolean isValidAsRDF(org.apache.jena.graph.Node g, org.apache.jena.graph.Node s, org.apache.jena.graph.Node p, org.apache.jena.graph.Node o)
      Determines whether a quad (as g/s/p/o) is valid as a RDF statement.

      This function reflects the fact that the Triple API is flexible in allowing any Node type in any position (including non-RDF node types like Variable) and as such not all Triples can be safely converted into Statements

      Parameters:
      s - Subject
      p - Predicate
      o - Object
      Returns:
      True if a valid as a statement

    • removeGeneralizedRDF

      public static StreamRDF removeGeneralizedRDF(StreamRDF data)
      Filter out triples and quads that are "generalized" RDF