Package org.apache.jackrabbit.oak.commons.internal.graph

Class Traverser

java.lang.Object

org.apache.jackrabbit.oak.commons.internal.graph.Traverser

public class Traverser
extends Object

Method Summary

Modifier and Type	Method	Description
static <T> @NotNull org.apache.commons.collections4.FluentIterable<T>	breadthFirstTraversal(T root, @NotNull Function<T,Iterable<? extends T>> childExtractor)	Returns an iterator that traverses a tree structure in breadth-first order.
static <T> org.apache.commons.collections4.FluentIterable<T>	postOrderTraversal(T root, Function<T,Iterable<? extends T>> childExtractor)	Returns an iterator that traverses a tree structure in post-order.
static <T> @NotNull org.apache.commons.collections4.FluentIterable<T>	preOrderTraversal(T root, @NotNull Function<T,Iterable<? extends T>> childExtractor)	Returns an iterator that traverses a tree structure in pre-order.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

preOrderTraversal

@NotNull
public static <T> @NotNull org.apache.commons.collections4.FluentIterable<T> preOrderTraversal(T root,
                                                                                               @NotNull
                                                                                               @NotNull Function<T,Iterable<? extends T>> childExtractor)

Returns an iterator that traverses a tree structure in pre-order. Null nodes are strictly forbidden.

In pre-order traversal, the current node is visited first, followed by its children from left to right. This method creates an iterator that produces tree nodes in this order.

Type Parameters:

T - the type of value in the tree nodes

Parameters:

root - the root node of the tree, may be null

childExtractor - function to extract children from a node, must not be null

Returns:

an iterator that traverses the tree in pre-order

Throws:

NullPointerException - if childExtractor or any child is null

breadthFirstTraversal

@NotNull
public static <T> @NotNull org.apache.commons.collections4.FluentIterable<T> breadthFirstTraversal(T root,
                                                                                                   @NotNull
                                                                                                   @NotNull Function<T,Iterable<? extends T>> childExtractor)

Returns an iterator that traverses a tree structure in breadth-first order. Null nodes are strictly forbidden.

In breadth-first traversal, all sibling nodes at a given level are visited before any nodes at the next level. This creates a level-by-level traversal pattern, starting from the root and moving downward through the tree.

Type Parameters:

T - the type of value in the tree nodes

Parameters:

root - the root node of the tree, may be null

childExtractor - function to extract children from a node, must not be null

Returns:

a fluent iterable that traverses the tree in breadth-first order

Throws:

NullPointerException - if childExtractor or any child is null

postOrderTraversal

public static <T> org.apache.commons.collections4.FluentIterable<T> postOrderTraversal(T root,
                                                                                       Function<T,Iterable<? extends T>> childExtractor)

Returns an iterator that traverses a tree structure in post-order. Null nodes are strictly forbidden.

In post-order traversal, all children of a node are visited from left to right, followed by the node itself. This creates a bottom-up traversal pattern where leaf nodes are visited first, then their parents, and finally the root.

Type Parameters:

T - the type of value in the tree nodes

Parameters:

root - the root node of the tree, may be null

childExtractor - function to extract children from a node, must not be null

Returns:

an iterator that traverses the tree in post-order

Throws:

NullPointerException - if childExtractor or any child is null