Class DlParser

java.lang.Object
org.tweetyproject.commons.Parser<DlBeliefSet,DlAxiom>
org.tweetyproject.logics.dl.parser.DlParser

public class DlParser extends Parser<DlBeliefSet,DlAxiom>
This class implements a parser for the description logic ALC (attributive concept language with complements). The input syntax is based on the input syntax of the Racer reasoner.
Note: Racer is built for the description logic SRIQ(D) (= the DL that corresponds to the OWL2 language), which is more expressive than ALC. SRIQ(D)-exclusive elements like inverse roles, role hierarchies and at-least restrictions are not supported by this parser. Furthermore, the syntax of universal and existential restrictions is different for reasons of simplification (see BNF).

The input syntax for an ALC knowledge base is given by the following BNF (starting symbol is KB):
KB ::== SIGNATURE FORMULAS
SIGNATURE ::== "signature(" (CONCEPT_DECLAR)? (ROLE_DECLAR)? (INDIVIDUAL_DECLAR)? ")"
CONCEPT_DECLAR ::== ("\n")* "atomic-concepts(" (CONCEPTNAME)* ")"
ROLE_DECLAR ::== ("\n")* "roles(" (ROLENAME)* ")"
INDIVIDUAL_DECLAR ::== ("\n")* "individuals(" (CONSTANTNAME)* ")"
AXIOMS ::== ("\n" AXIOM)*
AXIOM ::== "instance " " " CONSTANTNAME " " CONCEPT | "related " CONSTANTNAME " " CONSTANTNAME " " ROLENAME |
"implies " " " CONCEPT " " CONCEPT | "equivalent" CONCEPT " " CONCEPT
CONCEPT ::== "(" CONCEPT ")" | CONCEPTNAME | "not " CONCEPT | "*top*" | "*bottom*" | "top" | "bottom" |
"and " CONCEPT " " CONCEPT | "or " CONCEPT " " CONCEPT |
"forall " ROLENAME " " CONCEPT | "exists " ROLENAME " " CONCEPT

where CONCEPTNAME, ROLENAME, CONSTANTNAME are sequences of
symbols from {a,...,z,A,...,Z,0,...,9} with a letter at the beginning
excluding {"top","bottom"}.
Author:
Anna Gessler, Matthias Thimm
  • Constructor Details

    • DlParser

      public DlParser()
  • Method Details

    • parseBeliefBase

      public DlBeliefSet parseBeliefBase(Reader reader) throws IOException, ParserException
      Description copied from class: Parser
      Parses the given reader into a belief base of the given type.
      Specified by:
      parseBeliefBase in class Parser<DlBeliefSet,DlAxiom>
      Parameters:
      reader - a reader
      Returns:
      a belief base
      Throws:
      IOException - if some IO issue occurred.
      ParserException - some parsing exceptions may be added here.
    • parseFormula

      public DlAxiom parseFormula(Reader reader) throws IOException, ParserException
      Description copied from class: Parser
      Parses the given reader into a formula of the given type.
      Specified by:
      parseFormula in class Parser<DlBeliefSet,DlAxiom>
      Parameters:
      reader - a reader
      Returns:
      a formula
      Throws:
      IOException - if some IO issue occurred.
      ParserException - some parsing exceptions may be added here.
    • tokenize

      public void tokenize(Stack<Object> stack, int c)
      This method reads one character from the given reader and appropriately tokenizes it.
      Parameters:
      stack - used for monitoring the read items
      c - token from stream
    • setSignature

      public void setSignature(DlSignature signature)
      Sets the signature for this parser.
      Parameters:
      signature - a DL signature.
    • getSignature

      public DlSignature getSignature()
      Returns:
      the signature of this parser.