1 files changed, 52 insertions, 0 deletions

diff --git a/src/uk/ac/ox/cs/pagoda/constraints/UpperUnaryBottom.java b/src/uk/ac/ox/cs/pagoda/constraints/UpperUnaryBottom.java
new file mode 100644
index 0000000..2b57a52
--- /dev/null
+++ b/src/uk/ac/ox/cs/pagoda/constraints/UpperUnaryBottom.java
@@ -0,0 +1,52 @@
+package uk.ac.ox.cs.pagoda.constraints;
+
+import java.util.Collection;
+import java.util.HashMap;
+import java.util.LinkedList;
+import java.util.Map;
+
+import org.semanticweb.HermiT.model.Atom;
+import org.semanticweb.HermiT.model.AtomicConcept;
+import org.semanticweb.HermiT.model.DLClause;
+import org.semanticweb.HermiT.model.Term;
+import org.semanticweb.HermiT.model.Variable;
+
+public class UpperUnaryBottom extends UnaryBottom {
+        
+        static final Variable X = Variable.create("X"); 
+        
+        Map<DLClause, Integer> number = new HashMap<DLClause, Integer>(); 
+        
+        @Override
+        public Collection<DLClause> process(Collection<DLClause> clauses) {
+                Collection<DLClause> ret = new LinkedList<DLClause>(); 
+                for (DLClause clause: clauses) 
+                        if (clause.getHeadLength() == 0) {
+                                ret.add(DLClause.create(getEmptyHead(pickRepresentative(clause.getBodyAtoms()), clause), clause.getBodyAtoms())); 
+                                ret.add(DLClause.create(getEmptyHead(X), getEmptyHead(X, clause))); 
+                        }
+                        else 
+                                ret.add(clause); 
+                return ret;
+        }
+
+        @Override
+        public boolean isBottomRule(DLClause clause) {
+                return clause.getHeadLength() == 1 && clause.getHeadAtom(0).getDLPredicate().toString().contains(AtomicConcept.NOTHING.toString());
+        }
+
+        public Atom[] getEmptyHead(Term t, DLClause clause) {
+                Integer index = number.get(clause); 
+                if (index == null) {
+                        number.put(clause, index = number.size() + 1); 
+                }
+                
+                return new Atom[] {Atom.create(AtomicConcept.create(AtomicConcept.NOTHING.getIRI() + index), t)};
+        }
+        
+        @Override
+        public int getBottomNumber() {
+                return number.size() + 1; 
+        }
+
+}