Package com.espertech.esper.common.internal.epl.expression.visitor

Class ExprNodeIdentifierVisitor

java.lang.Object
com.espertech.esper.common.internal.epl.expression.visitor.ExprNodeIdentifierVisitor
All Implemented Interfaces:
ExprNodeVisitor
public class ExprNodeIdentifierVisitor extends Object implements ExprNodeVisitor
Visitor that collects event property identifier information under expression nodes. The visitor can be configued to not visit aggregation nodes thus ignoring properties under aggregation nodes such as sum, avg, min/max etc.

  • Constructor Details

    • ExprNodeIdentifierVisitor

      public ExprNodeIdentifierVisitor(boolean visitAggregateNodes)
      Ctor.
      Parameters:
      visitAggregateNodes - true to indicate that the visitor should visit aggregate nodes, or false if the visitor ignores aggregate nodes

  • Method Details

    • isVisit

      public boolean isVisit(ExprNode exprNode)
      Description copied from interface: ExprNodeVisitor
      Allows visitor to indicate whether to visit a given node. Implicitly if a visitor doesn't visit a node it would also not visit any descendent child nodes of that node.
      Specified by:
      isVisit in interface ExprNodeVisitor
      Parameters:
      exprNode - is the node in questions
      Returns:
      true if the visitor wants to visit the child node (next call is visit), or false to skip child

    • getExprProperties

      public List<Pair<Integer,String>> getExprProperties()
      Returns list of event property stream numbers and names that uniquely identify which property is from whcih stream, and the name of each.
      Returns:
      list of event property statement-unique info

    • visit

      public void visit(ExprNode exprNode)
      Description copied from interface: ExprNodeVisitor
      Visit the given expression node.
      Specified by:
      visit in interface ExprNodeVisitor
      Parameters:
      exprNode - is the expression node to visit