java.lang.Object
- com.apicatalog.tree.io.NodeVisitor

Direct Known Subclasses:

NodeGenerator
```
public class NodeVisitor
extends java.lang.Object
```
A non-recursive depth-first traversal for arbitrary trees.
Traverses trees in depth-first order, visiting nodes one at a time via step(). The traversal distinguishes between the root node, map property keys and values, and collection elements using NodeVisitor.Context.

Traversal rules:
- When visiting a map-like node, keys are visited before their corresponding values.
- When visiting a collection or array node, elements are visited in insertion order.
- Other node types are visited directly.
Traversal proceeds until all nodes have been visited or limits (maximum depth or maximum nodes) are reached.

Nested Class Summary

Nested Classes
Modifier and Type Class Description

static class NodeVisitor.Context
Indicates the role of the node during traversal.

Field Summary

Fields
Modifier and Type	Field	Description
`protected NodeAdapter`	`adapter`	Adapter providing access to node types and children.
`protected long`	`depth`	Current depth.
`protected java.util.Comparator<java.util.Map.Entry<?,?>>`	`entryComparator`	Comparator for map entries.
`protected int`	`maxDepth`	Maximum depth allowed during traversal.
`protected int`	`maxVisited`	Maximum number of nodes allowed to be visited.
`protected java.lang.Object`	`node`	Current node.
`protected NodeVisitor.Context`	`nodeContext`	Role of the current node.
`protected NodeType`	`nodeType`	Type of the current node.
`protected java.util.Deque<java.lang.Object>`	`stack`	Stack used for traversal.
`static int`	`UNLIMITED_DEPTH`	Sentinel value indicating no maximum depth limit.
`static int`	`UNLIMITED_NODES`	Sentinel value indicating no maximum node visit limit.
`protected long`	`visited`	Number of nodes visited.

Constructor Summary

Constructors
Modifier	Constructor	Description
`protected`	`NodeVisitor(java.util.Deque<java.lang.Object> stack, NodeAdapter adapter)`	Creates a new traversal with the given stack and adapter.
`protected`	`NodeVisitor(java.util.Deque<java.lang.Object> stack, NodeAdapter adapter, java.util.Comparator<java.util.Map.Entry<?,?>> entryComparator)`

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`void`	`keyComparator(java.util.Comparator<java.util.Map.Entry<?,?>> keyComparator)`	Sets the comparator used to order map property keys during traversal.
`int`	`maxDepth()`	Returns the maximum depth allowed during traversal.
`void`	`maxDepth(int maxDepth)`	Sets the maximum depth of traversal.
`int`	`maxVisited()`	Returns the maximum number of nodes that can be visited during traversal.
`void`	`maxVisited(int maxVisitedNodes)`	Sets the maximum number of nodes that can be visited during traversal.
`static NodeVisitor`	`of(java.lang.Object root, NodeAdapter adapter)`	Creates a new `NodeVisitor` starting at the given root node, using the default property key ordering - insertion order.
`static NodeVisitor`	`of(java.lang.Object root, NodeAdapter adapter, java.util.Comparator<java.util.Map.Entry<?,?>> propertyComparator)`	Creates a new `NodeVisitor` starting at the given root node, using a custom comparator for ordering map property keys.
`void`	`reset(java.lang.Object node, NodeAdapter adapter)`	Resets the traversal with a new root node and adapter.
`boolean`	`step()`	Advances the traversal by one step.
`long`	`visited()`	Returns the number of nodes visited.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - UNLIMITED_DEPTH
```
public static final int UNLIMITED_DEPTH
```
    Sentinel value indicating no maximum depth limit.
    
    See Also:
    
    Constant Field Values
  - UNLIMITED_NODES
```
public static final int UNLIMITED_NODES
```
    Sentinel value indicating no maximum node visit limit.
    
    See Also:
    
    Constant Field Values
  - maxVisited
```
protected int maxVisited
```
    Maximum number of nodes allowed to be visited.
  - maxDepth
```
protected int maxDepth
```
    Maximum depth allowed during traversal.
  - stack
```
protected final java.util.Deque<java.lang.Object> stack
```
    Stack used for traversal.
  - entryComparator
```
protected java.util.Comparator<java.util.Map.Entry<?,?>> entryComparator
```
    Comparator for map entries.
  - adapter
```
protected NodeAdapter adapter
```
    Adapter providing access to node types and children.
  - depth
```
protected long depth
```
    Current depth.
  - visited
```
protected long visited
```
    Number of nodes visited.
  - node
```
protected java.lang.Object node
```
    Current node.
  - nodeType
```
protected NodeType nodeType
```
    Type of the current node.
  - nodeContext
```
protected NodeVisitor.Context nodeContext
```
    Role of the current node.
- Constructor Detail
  - NodeVisitor
```
protected NodeVisitor(java.util.Deque<java.lang.Object> stack,
                      NodeAdapter adapter)
```
    Creates a new traversal with the given stack and adapter.
    
    Parameters:
    
    stack - the stack to use for traversal state
    
    adapter - the adapter providing node access
  - NodeVisitor
```
protected NodeVisitor(java.util.Deque<java.lang.Object> stack,
                      NodeAdapter adapter,
                      java.util.Comparator<java.util.Map.Entry<?,?>> entryComparator)
```
- Method Detail
  - of
```
public static NodeVisitor of(java.lang.Object root,
                             NodeAdapter adapter)
```
    Creates a new NodeVisitor starting at the given root node, using the default property key ordering - insertion order.
    
    Parameters:
    
    root - the root node to start traversal from, must not be null
    
    adapter - the adapter providing access to node types and children, must not be null
    
    Returns:
    
    a new NodeVisitor instance positioned at the root node
    
    Throws:
    
    java.lang.NullPointerException - if root or adapter is null
  - of
```
public static NodeVisitor of(java.lang.Object root,
                             NodeAdapter adapter,
                             java.util.Comparator<java.util.Map.Entry<?,?>> propertyComparator)
```
    Creates a new NodeVisitor starting at the given root node, using a custom comparator for ordering map property keys.
    
    Parameters:
    
    root - the root node to start traversal from, must not be null
    
    adapter - the adapter providing access to node types and children, must not be null
    
    propertyComparator - comparator used to order map keys during traversal, must not be null
    
    Returns:
    
    a new NodeVisitor instance positioned at the root node
    
    Throws:
    
    java.lang.NullPointerException - if root, adapter, or propertyComparator is null
  - step
```
public boolean step()
```
    Advances the traversal by one step.
    Processes exactly one node, updating node, nodeType, and nodeContext to describe it. Subsequent calls continue traversal until the entire tree has been visited.
    
    Returns:
    
    true if a node was processed, or false if traversal is complete
    
    Throws:
    
    java.lang.IllegalStateException - if the traversal exceeds the maximum node count or the maximum depth configured via maxVisited(int) or maxDepth(int)
  - visited
```
public long visited()
```
    Returns the number of nodes visited.
  - reset
```
public void reset(java.lang.Object node,
                  NodeAdapter adapter)
```
    Resets the traversal with a new root node and adapter.
    
    Parameters:
    
    node - the new root node
    
    adapter - the adapter providing access to node types
  - keyComparator
```
public void keyComparator(java.util.Comparator<java.util.Map.Entry<?,?>> keyComparator)
```
    Sets the comparator used to order map property keys during traversal.
    The comparator determines the order in which map keys are visited. By default, keys are visited in insertion order if no comparator is set.
    
    Parameters:
    
    keyComparator - comparator for map keys; must not be null
  - maxDepth
```
public void maxDepth(int maxDepth)
```
    Sets the maximum depth of traversal.
    If the traversal reaches this depth, further children will not be visited. Use UNLIMITED_DEPTH (-1) to indicate no depth limit (default).
    
    Parameters:
    
    maxDepth - maximum depth allowed during traversal
  - maxDepth
```
public int maxDepth()
```
    Returns the maximum depth allowed during traversal.
    
    Returns:
    
    maximum depth; -1 if no limit
  - maxVisited
```
public void maxVisited(int maxVisitedNodes)
```
    Sets the maximum number of nodes that can be visited during traversal.
    If the number of visited nodes reaches this limit, step() will throw IllegalStateException. Use UNLIMITED_NODES (-1) to indicate no limit (default).
    
    Parameters:
    
    maxVisitedNodes - maximum number of nodes to visit
  - maxVisited
```
public int maxVisited()
```
    Returns the maximum number of nodes that can be visited during traversal.
    
    Returns:
    
    maximum number of nodes; -1 if no limit

Class NodeVisitor

Nested Class Summary

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

UNLIMITED_DEPTH

UNLIMITED_NODES

maxVisited

maxDepth

stack

entryComparator

adapter

depth

visited

node

nodeType

nodeContext

Constructor Detail

NodeVisitor

NodeVisitor

Method Detail

of

of

step

visited

reset

keyComparator

maxDepth

maxDepth

maxVisited

maxVisited