Class BaseDatatype

All Implemented Interfaces:
Direct Known Subclasses:
AdhocDatatype, FunctorDatatype, RDFDirLangString, RDFhtml, RDFjson, RDFLangString, XMLLiteralType, XMLLiteralType0, XSDDatatype

public class BaseDatatype extends Object implements RDFDatatype
Base level implementation of datatype from which real implementations can inherit.
  • Constructor Details

    • BaseDatatype

      public BaseDatatype(String uri)
      uri - the URI label to use for this datatype
  • Method Details

    • getURI

      public String getURI()
      Return the URI which is the label for this datatype
      Specified by:
      getURI in interface RDFDatatype
    • unparse

      public String unparse(Object value)
      Convert a value of this datatype out to lexical form.
      Specified by:
      unparse in interface RDFDatatype
    • parse

      public Object parse(String lexicalForm) throws DatatypeFormatException
      Parse a lexical form of this datatype to a value
      Specified by:
      parse in interface RDFDatatype
      DatatypeFormatException - if the lexical form is not legal
    • isValid

      public boolean isValid(String lexicalForm)
      Test whether the given string is a legal lexical form of this datatype.
      Specified by:
      isValid in interface RDFDatatype
    • isValidLiteral

      public boolean isValidLiteral(LiteralLabel lit)
      Test whether the given LiteralLabel is a valid instance of this datatype. This takes into account typing information as well as lexical form - for example an xsd:string is never considered valid as an xsd:integer (even if it is lexically legal like "1").
      Specified by:
      isValidLiteral in interface RDFDatatype
    • isValidValue

      public boolean isValidValue(Object valueForm)
      Test whether the given object is a legal value form of this datatype.
      Specified by:
      isValidValue in interface RDFDatatype
    • isEqual

      public boolean isEqual(LiteralLabel litLabel1, LiteralLabel litLabel2)
      Compares two instances of values of the given datatype. This default requires value and datatype equality.
      Specified by:
      isEqual in interface RDFDatatype
    • getHashCode

      public int getHashCode(LiteralLabel lit)
      Default implementation of getHashCode() delegates to the default from the literal label.
      Specified by:
      getHashCode in interface RDFDatatype
    • langTagCompatible

      public boolean langTagCompatible(LiteralLabel value1, LiteralLabel value2)
      Helper function to compare language tag values
    • getJavaClass

      public Class<?> getJavaClass()
      Returns the java class which is used to represent value instances of this datatype.
      Specified by:
      getJavaClass in interface RDFDatatype
    • cannonicalise

      public Object cannonicalise(Object value)
      Cannonicalise a java Object value to a normal form. Primarily used in cases such as xsd:integer to reduce the Java object representation to the narrowest of the Number subclasses to ensure that indexing of typed literals works.
      Specified by:
      cannonicalise in interface RDFDatatype
    • extendedTypeDefinition

      public Object extendedTypeDefinition()
      Returns an object giving more details on the datatype. This is type system dependent. In the case of XSD types this will be an instance of org.apache.xerces.impl.xs.psvi.XSTypeDefinition.
      Specified by:
      extendedTypeDefinition in interface RDFDatatype
    • normalizeSubType

      public RDFDatatype normalizeSubType(Object value, RDFDatatype dt)
      Normalization. If the value is narrower than the current data type (e.g. value is xsd:date but the time is xsd:datetime) returns the narrower type for the literal. If the type is narrower than the value then it may normalize the value (e.g. set the mask of an XSDDateTime) Currently only used to narrow gener XSDDateTime objects to the minimal XSD date/time type.
      Specified by:
      normalizeSubType in interface RDFDatatype
      value - the current object value
      dt - the currently set data type
      a narrower version of the datatype based on the actual value range
    • toString

      public String toString()
      Display format
      toString in class Object