private void gatherPositionAndOccurrenceInfo ( Term clause ) { PositionalTermTraverser positionalTraverser = new PositionalTermTraverserImpl ( ) ; PositionAndOccurrenceVisitor positionAndOccurrenceVisitor = new PositionAndOccurrenceVisitor ( interner , symbolTable , positionalTraverser ) ; positionalTraverser . setContextChangeVisitor ( positionAndOccurrenceVisitor ) ; TermWalker walker = new TermWalker ( new DepthFirstBacktrackingSearch < Term , Term > ( ) , positionalTraverser , positionAndOccurrenceVisitor ) ; walker . walk ( clause ) ; }
Gather information about variable counts and positions of occurrence of constants and variable within a clause .