GroundLiteral.java

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package edu.tum.cs.logic;

import java.util.Map;
import java.util.Set;

import edu.tum.cs.srl.Database;

public class GroundLiteral extends Formula {
        public boolean isPositive;
        public GroundAtom gndAtom;
        
        public GroundLiteral(boolean isPositive, GroundAtom gndAtom) {
                this.gndAtom = gndAtom;
                this.isPositive = isPositive;
        }
        
        public boolean isTrue(IPossibleWorld w) {
                boolean v = w.isTrue(gndAtom);
                return isPositive ? v : !v;
        }

        @Override
        public void getVariables(Database db, Map<String, String> ret) {
        }

        @Override
        public Formula ground(Map<String, String> binding, WorldVariables vars, Database db) throws Exception {
                return this;
        }

        @Override
        public void getGroundAtoms(Set<GroundAtom> ret) {   
            ret.add(gndAtom);              
        }
        
        @Override
        public String toString() {
                return isPositive ? gndAtom.toString() : "!" + gndAtom.toString();
        }

        @Override
        public Formula toCNF() {                
                return this;
        }

        @Override
        public Formula toNNF() {                
                return this;
        }
        
        public void negate() {
                isPositive = !isPositive;
        }

    @Override
    public Formula simplify(Database evidence) {
        Formula f = this.gndAtom.simplify(evidence);
        if(f instanceof TrueFalse) {
                if(isPositive)
                        return f;
                else
                        return ((TrueFalse)f).opposite();               
        }
        return this;
    }
}

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srldb
Author(s): Dominik Jain, Stefan Waldherr, Moritz Tenorth
autogenerated on Fri Jan 11 09:58:29 2013