Package org.apache.commons.configuration2.tree

Interface ConfigurationNodeVisitor<T>

Type Parameters:
T - the type of the nodes processed by this visitor
All Known Implementing Classes:
BaseHierarchicalConfiguration.BuilderVisitor, ConfigurationNodeVisitorAdapter
public interface ConfigurationNodeVisitor<T>

Definition of a Visitor interface for a configuration node structure.

This is a typical application of the GoF Visitor pattern. An object implementing this interface can be used to traverse a hierarchical structure of nodes in various ways. The type of the nodes in the structure is generic; a corresponding NodeHandler implementation must be available for navigating through the structure.

Note that the exact way the methods of a ConfigurationNodeVisitor are invoked is dependent on a specific traversal process.

Since:
1.3

  • Method Summary

    Modifier and Type
    Method
    Description
    boolean
    terminate()
    Returns a flag whether the current visit process should be aborted.
    void
    visitAfterChildren(T node, NodeHandler<T> handler)
    Visits the specified node after after its children - if existing - have been processed.
    void
    visitBeforeChildren(T node, NodeHandler<T> handler)
    Visits the specified node before the children of this node - if existing - are processed.

  • Method Details

    • terminate

      boolean terminate()
      Returns a flag whether the current visit process should be aborted. This method allows a visitor implementation to state that it does not need any further data. It may be used e.g. by visitors that search for a certain node in the hierarchy. After that node was found, there is no need to process the remaining nodes, too. This method is called after each visited node. A result of true indicates that the current iteration is to be aborted.
      Returns:
      a flag if the visit process should be stopped

    • visitAfterChildren

      void visitAfterChildren(T node, NodeHandler<T> handler)
      Visits the specified node after after its children - if existing - have been processed.
      Parameters:
      node - the node to be visited
      handler - the NodeHandler

    • visitBeforeChildren

      void visitBeforeChildren(T node, NodeHandler<T> handler)
      Visits the specified node before the children of this node - if existing - are processed.
      Parameters:
      node - the node to be visited
      handler - the NodeHandler