Package org.tweetyproject.lp.asp.syntax

Class Program

java.lang.Object
java.util.AbstractCollection<E>
java.util.AbstractSet<E>
java.util.HashSet<T>
org.tweetyproject.commons.util.rules.RuleSet<ASPRule>
org.tweetyproject.lp.asp.syntax.Program
All Implemented Interfaces:
Serializable, Cloneable, Iterable<ASPRule>, Collection<ASPRule>, Set<ASPRule>, BeliefBase, LogicProgram<ClassicalHead,​ASPBodyElement,​ASPRule>
public class Program extends RuleSet<ASPRule> implements LogicProgram<ClassicalHead,​ASPBodyElement,​ASPRule>
This class models an ASP-Core-2 program, meaning a set of rules and optionally a query. A program is ground if it contains no variables. The rules are ordered alphabetically.
Author:
Tim Janus, Thomas Vengels, Anna Gessler
See Also:
Serialized Form

  • Constructor Details

    • Program

      public Program()
      Creates a new empty program.

    • Program

      public Program​(Collection<ASPRule> rules)
      Creates a new program with the given rules.
      Parameters:
      rules - a set of rules

    • Program

      public Program​(ASPRule... rules)
      Creates a new program with the given rules.
      Parameters:
      rules - a set of rules

    • Program

      public Program​(ASPLiteral query, Set<ASPRule> rules)
      Creates a new program with the given query and rules.
      Parameters:
      query - a query
      rules - a set of rules

    • Program

      public Program​(Program other)
      Copy-Constructor
      Parameters:
      other - another program

  • Method Details

    • setQuery

      public void setQuery​(ASPLiteral query)
      Sets the query of the program.
      Parameters:
      query - a literal

    • addFact

      public void addFact​(ClassicalHead fact)
      Description copied from interface: LogicProgram
      Adds the given fact to the program
      Specified by:
      addFact in interface LogicProgram<ClassicalHead,​ASPBodyElement,​ASPRule>
      Parameters:
      fact - a fact

    • addFacts

      public void addFacts​(ClassicalHead... fact)
      Description copied from interface: LogicProgram
      Adds the given facts to the program
      Specified by:
      addFacts in interface LogicProgram<ClassicalHead,​ASPBodyElement,​ASPRule>
      Parameters:
      fact - some facts

    • setOutputWhitelist

      public void setOutputWhitelist​(Collection<Predicate> ps)
      Sets the whitelist of predicates. Solvers that use this option will only show atoms over predicates in this set in their output.
      Parameters:
      ps - set of predicates

    • addToOutputWhitelist

      public boolean addToOutputWhitelist​(Predicate p)
      Adds the given predicate to the whitelist of predicates. Solvers that use this option will only show atoms over predicates in this set in their output.
      Parameters:
      p - a Predicate
      Returns:
      if the whitelist did not already contain the specified element

    • getOutputWhitelist

      public Set<Predicate> getOutputWhitelist()
      Returns the whitelist of predicates. Solvers that use this option will only show atoms over predicates in this set in their output.
      Returns:
      set of whitelisted predicates

    • hasQuery

      public boolean hasQuery()
      Returns true if the program contains a query.
      Returns:
      true if the program has a query, false otherwise

    • getQuery

      public ASPLiteral getQuery()
      Returns the query of the program, if there is one.
      Returns:
      a literal, or null if the program has no query

    • addFact

      public void addFact​(ASPLiteral fact)
      Adds a fact to this program.
      Parameters:
      fact - a literal

    • add

      public void add​(Program other)
      Adds another program's content to the content of this program.
      Parameters:
      other - Reference to the other program.

    • getAdditionalOptions

      public Set<String> getAdditionalOptions()
      Returns:
      additional options for solvers

    • setAdditionalOptions

      public void setAdditionalOptions​(Set<String> additionalOptions)
      Set additional options for solvers.
      Parameters:
      additionalOptions - commandLineArguments in the format "option=value"

    • isExtendedProgram

      public boolean isExtendedProgram()
      Checks if the program is an extended program, meaning the heads of the literals do not have more than one literal.
      Returns:
      True if the program is an extended program, false otherwise.

    • isSafe

      public boolean isSafe()
      Returns true if the program is safe, i.e. if all of its rules and its query are safe according to the definition of safety given in the ASP-Core-2 standard.
      Returns:
      true if the program is safe, false otherwise

    • isGround

      public boolean isGround()
      Checks if the program is ground, meaning if it contains no rules with variables.
      Returns:
      true if the program is ground, false otherwise

    • getMinimalSignature

      public FolSignature getMinimalSignature()
      Description copied from interface: BeliefBase
      Returns the signature of the language of this knowledge base.
      Specified by:
      getMinimalSignature in interface BeliefBase
      Specified by:
      getMinimalSignature in interface LogicProgram<ClassicalHead,​ASPBodyElement,​ASPRule>
      Returns:
      the signature of the language of this knowledge base.

    • substitute

      public Program substitute​(Term<?> v, Term<?> t) throws IllegalArgumentException
      Description copied from interface: LogicProgram
      Substitutes all occurrences of term "v" in this formula by term "t" and returns the new formula.
      Specified by:
      substitute in interface LogicProgram<ClassicalHead,​ASPBodyElement,​ASPRule>
      Parameters:
      v - the term to be substituted.
      t - the term to substitute.
      Returns:
      a formula where every occurrence of "v" is replaced by "t".
      Throws:
      IllegalArgumentException - if "v" and "t" are of different sorts

    • substitute

      public Program substitute​(Map<? extends Term<?>,​? extends Term<?>> map) throws IllegalArgumentException
      Description copied from interface: LogicProgram
      Substitutes all occurrences of all terms "v" in map.keyset() in this formula by map.get(v) and returns the new formula.
      Specified by:
      substitute in interface LogicProgram<ClassicalHead,​ASPBodyElement,​ASPRule>
      Parameters:
      map - a mapping defining which terms to be substituted.
      Returns:
      a formula where every term in map.keyset() has been replaced by map.get(v).
      Throws:
      IllegalArgumentException - if any term and its mapping are of different sorts

    • exchange

      public Program exchange​(Term<?> v, Term<?> t) throws IllegalArgumentException
      Description copied from interface: LogicProgram
      Substitutes all occurrences of term "v" in this formula by term "t" and at the same time replaces all occurrences of term "t" by term "v" and eventually returns the new formula.
      Specified by:
      exchange in interface LogicProgram<ClassicalHead,​ASPBodyElement,​ASPRule>
      Parameters:
      v - a term.
      t - a term.
      Returns:
      a new logical formula with both "v" and "t" exchanged.
      Throws:
      IllegalArgumentException - if "v" and "t" are of different sorts

    • clone

      public Program clone()
      Overrides:
      clone in class HashSet<ASPRule>

    • getReduct

      public Program getReduct​(Set<ASPLiteral> state)
      Returns the reduct of this program wrt. the given state, i.e. a program that contains no default negation and only those rules of this program (without all default-negated literals in the body) that do not have a default-negated version of a literal in their body.
      Parameters:
      state - some set of literals
      Returns:
      the reduct of this program

    • getDefaultification

      public static Program getDefaultification​(Program p)
      Creates the defaultification p_d of a given program p. A defaultificated program p' of p adds for every Rule r in p a modified rule r_d of the form: 'H(r) :- B(r), not -H(r).' to the program p'.
      Parameters:
      p - The program which is not defaultificated yet
      Returns:
      a program p' which is the defaultificated version of p.

    • toString

      public String toString()
      Specified by:
      toString in interface BeliefBase
      Specified by:
      toString in interface LogicProgram<ClassicalHead,​ASPBodyElement,​ASPRule>
      Overrides:
      toString in class AbstractCollection<ASPRule>

    • hashCode

      public int hashCode()
      Specified by:
      hashCode in interface Collection<ASPRule>
      Specified by:
      hashCode in interface Set<ASPRule>
      Overrides:
      hashCode in class AbstractSet<ASPRule>

    • equals

      public boolean equals​(Object obj)
      Specified by:
      equals in interface Collection<ASPRule>
      Specified by:
      equals in interface Set<ASPRule>
      Overrides:
      equals in class AbstractSet<ASPRule>