Interface NodeFilter


public interface NodeFilter
Node filter interface. Provide an implementing class to NodeTraversor to iterate through nodes.

This interface provides two methods, head and tail. The head method is called when the node is first seen, and the tail method when all of the node's children have been visited. As an example, head can be used to create a start tag for a node, and tail to create the end tag.

For every node, the filter has to decide whether to

The difference between NodeFilter.FilterResult.SKIP_CHILDREN and NodeFilter.FilterResult.SKIP_ENTIRELY is that the first will invoke tail(Node, int) on the node, while the latter will not. Within tail(Node, int), both are equivalent to NodeFilter.FilterResult.CONTINUE.

  • Nested Class Summary

    Nested Classes 
    Modifier and Type Interface Description
    static class  NodeFilter.FilterResult
    Filter decision.
  • Method Summary

    Modifier and Type Method Description
    NodeFilter.FilterResult head​(Node node, int depth)
    Callback for when a node is first visited.
    NodeFilter.FilterResult tail​(Node node, int depth)
    Callback for when a node is last visited, after all of its descendants have been visited.
  • Method Details

    • head

      NodeFilter.FilterResult head​(Node node, int depth)
      Callback for when a node is first visited.
      Parameters:
      node - the node being visited.
      depth - the depth of the node, relative to the root node. E.g., the root node has depth 0, and a child node of that will have depth 1.
      Returns:
      Filter decision
    • tail

      NodeFilter.FilterResult tail​(Node node, int depth)
      Callback for when a node is last visited, after all of its descendants have been visited.
      Parameters:
      node - the node being visited.
      depth - the depth of the node, relative to the root node. E.g., the root node has depth 0, and a child node of that will have depth 1.
      Returns:
      Filter decision