How to use

shallowCopy

method

in

org.apache.jena.sparql.syntax.syntaxtransform.QueryTransformOps

private static void testShallowCopy(String queryString)
{
  Query q1 = QueryFactory.create(queryString) ;
  Query q2 = QueryTransformOps.shallowCopy(q1) ;
  assertEquals(q1, q2) ;
}

/** Transform a query using {@link ElementTransform} and {@link ExprTransform}.
 *  It is the responsibility of these transforms to transform to a legal SPARQL query.
 */ 
public static Query transform(Query query, ElementTransform transform, ExprTransform exprTransform) {
  Query q2 = QueryTransformOps.shallowCopy(query);
  // "Shallow copy with transform."
  transformVarExprList(q2.getProject(), exprTransform);
  transformVarExprList(q2.getGroupBy(), exprTransform);
  transformExprList(q2.getHavingExprs(), exprTransform);
  if (q2.getOrderBy() != null) {
    transformSortConditions(q2.getOrderBy(), exprTransform);
  }
  // ?? DOES NOT WORK: transformExprListAgg(q2.getAggregators(), exprTransform) ; ??
  // if ( q2.hasHaving() ) {}
  // if ( q2.hasAggregators() ) {}
  Element el = q2.getQueryPattern();
  Element el2 = ElementTransformer.transform(el, transform, exprTransform);
  // Top level is always a group.
  if (!(el2 instanceof ElementGroup)) {
    ElementGroup eg = new ElementGroup();
    eg.addElement(el2);
    el2 = eg;
  }
  q2.setQueryPattern(el2);
  return q2;
}