Java Code Examples for org.eclipse.rdf4j.query.algebra.StatementPattern#getVarList()

@Override
protected double getCardinality(StatementPattern sp) {
    //always preffer HALYARD.SEARCH_TYPE object literals to move such statements higher in the joins tree
    Var objectVar = sp.getObjectVar();
    if (objectVar.hasValue() && (objectVar.getValue() instanceof Literal) && HALYARD.SEARCH_TYPE.equals(((Literal) objectVar.getValue()).getDatatype())) {
        return 0.0001;
    }
    Double card = spcalc == null ? null : spcalc.getCardinality(sp, boundVars);
    if (card == null) { //fallback to default cardinality calculation
        card = (hasValue(sp.getSubjectVar(), boundVars) ? 1.0 : 10.0) * (hasValue(sp.getPredicateVar(), boundVars) ? 1.0 : 10.0) * (hasValue(sp.getObjectVar(), boundVars) ? 1.0 : 10.0) * (hasValue(sp.getContextVar(), boundVars) ? 1.0 : 10.0);
    }
    for (Var v : sp.getVarList()) {
        //decrease cardinality for each priority variable present
        if (v != null && priorityVariables.contains(v.getName())) card /= 1000000.0;
    }
    return card;
}
 

/**
 * returns true iff there is at least one free variable, i.e. there is no binding for any variable
 *
 * @param stmt
 * @param bindings
 * @return whether free vars are available
 */
public static boolean hasFreeVars(StatementPattern stmt, BindingSet bindings) {
	for (Var var : stmt.getVarList()) {
		if (!var.hasValue() && !bindings.hasBinding(var.getName())) {
			return true; // there is at least one free var
		}
	}
	return false;
}
 

/**
 * returns true iff there is at least one free variable, i.e. there is no binding for any variable
 *
 * @param stmt
 * @param bindings
 * @return whether there is at least one free variable
 */
public static boolean hasFreeVars(StatementPattern stmt, BindingSet bindings) {
	for (Var var : stmt.getVarList()) {
		if (!var.hasValue() && !bindings.hasBinding(var.getName())) {
			return true; // there is at least one free var
		}
	}
	return false;
}
 

private int numberOfSpVars(StatementPattern sp) {
    List<Var> varList = sp.getVarList();
    int varCount = 0;

    for(int i = 0; i < 3; i++) {
       if(!varList.get(i).isConstant()) {
           varCount++;
       }
    }

    return varCount;
}
 

private Set<String> getVariableNames() {
    final Set<String> vars = new HashSet<>();
    for (final StatementPattern pattern : patterns) {
        for (final Var var : pattern.getVarList()) {
            if (var.getValue() == null) {
                vars.add(var.getName());
            }
        }
    }
    return vars;
}
 

public static String getRow(StatementPattern sp, boolean joinTable) {

    String row = "";
    String values = "";
    List<Var> varList = sp.getVarList();
    List<String> constList = CardinalityCalcUtil.getConstantPos(sp);
    int i;

    for (String s : constList) {

      i = CardinalityCalcUtil.triplePlaceToInt(s);

      if (row.equals("subject") && s.equals("object") && joinTable) {
        row = s + row;
        if (values.length() == 0) {
          values = values + removeQuotes(varList.get(i).getValue().toString());
        } else {
          values = removeQuotes(varList.get(i).getValue().toString()) + DELIM + values;
        }
      } else {
        row = row + s;
        if (values.length() == 0) {
          values = values + removeQuotes(varList.get(i).getValue().toString());
        } else {
          values = values + DELIM + removeQuotes(varList.get(i).getValue().toString());
        }
      }

    }

    return (row + DELIM + values);

  }
 

private static List<String> getJoinType(StatementPattern sp1, StatementPattern sp2) {

    List<String> joinList = new ArrayList<String>();
    List<Var> spList1 = sp1.getVarList();
    List<Var> spList2 = sp2.getVarList();

    List<String> pos1 = CardinalityCalcUtil.getVariablePos(sp1);
    List<String> pos2 = CardinalityCalcUtil.getVariablePos(sp2);

    int i, j;

    for (String s : pos1) {
      for (String t : pos2) {
        i = CardinalityCalcUtil.triplePlaceToInt(s);
        j = CardinalityCalcUtil.triplePlaceToInt(t);

        if (spList1.get(i).getName().equals(spList2.get(j).getName())) {
          joinList.add(s);
          joinList.add(t);

        }

      }
    }
    if (joinList.size() == 4) {
      return orderJoinType(joinList);
    }

    return joinList;

  }
 

protected double getCardinality(StatementPattern pattern) {
	Set<Var> vars = new HashSet<>(pattern.getVarList());
	int constantVarCount = countConstantVars(vars);
	double unboundVarFactor = (double) (vars.size() - constantVarCount) / vars.size();
	return Math.pow(1000.0, unboundVarFactor);
}
 

private static boolean genConstantCompare(StatementPattern queryNode, StatementPattern indexNode) {
    
    

    ArrayList<Var> vars1 = (ArrayList<Var>) queryNode.getVarList();
    ArrayList<Var> vars2 = (ArrayList<Var>) indexNode.getVarList();

    
    for (int i = 0; i < vars1.size(); i++) {

        if (vars1.get(i).isConstant() && vars2.get(i).isConstant()) {

            if (!vars1.get(i).equals(vars2.get(i))) {
                return false;

            }

        } else if(!vars1.get(i).isConstant() && vars2.get(i).isConstant() ) {
                return false;
        }

    }

    return true;

}
 

/**
 * returns true iff there is at least one free variable, i.e. there is no binding
 * for any variable
 * 
 * @param stmt
 * @param bindings
 * @return
 */
public static boolean hasFreeVars(StatementPattern stmt, BindingSet bindings) {
	for (Var var : stmt.getVarList()) {
		if(!var.hasValue() && !bindings.hasBinding(var.getName()))
			return true;	// there is at least one free var				
	}
	return false;
}
 

/**
 * returns true iff there is at least one free variable, i.e. there is no binding
 * for any variable
 * 
 * @param stmt
 * @param bindings
 * @return
 */
public static boolean hasFreeVars(StatementPattern stmt, BindingSet bindings) {
	for (Var var : stmt.getVarList()) {
		if(!var.hasValue() && !bindings.hasBinding(var.getName()))
			return true;	// there is at least one free var				
	}
	return false;
}
 

private static List<String> getVariablePos(StatementPattern sp) {

    List<String> posList = new ArrayList<String>();
    List<Var> varList = sp.getVarList();

    for (int i = 0; i < 3; i++) {
      if (!varList.get(i).isConstant()) {
        posList.add(intToTriplePlace(i));

      }
    }

    return posList;

  }
 

private static List<String> getConstantPos(StatementPattern sp) {

    List<String> posList = new ArrayList<String>();
    List<Var> varList = sp.getVarList();

    for (int i = 0; i < 3; i++) {
      if (varList.get(i).isConstant()) {
        posList.add(intToTriplePlace(i));

      }
    }

    return posList;

  }