code: package it.unibz.inf.ontop.iq.node.normalization;
  
  import com.google.common.collect.ImmutableList;
  import it.unibz.inf.ontop.iq.IQTree;
  import it.unibz.inf.ontop.iq.IQTreeCache;
  import it.unibz.inf.ontop.iq.node.InnerJoinNode;
  import it.unibz.inf.ontop.utils.VariableGenerator;
  
  public interface InnerJoinNormalizer {
  
      IQTree normalizeForOptimization(InnerJoinNode innerJoinNode, ImmutableList<IQTree> children, VariableGenerator variableGenerator,
                                      IQTreeCache treeCache);
  }
  