PreorderEnumeration (Web API 2021)

java.lang.Object
- com.microstrategy.utils.FlattenedEnumerationBase
- - com.microstrategy.utils.PreorderEnumeration

All Implemented Interfaces:

java.util.Enumeration
```
public class PreorderEnumeration
extends FlattenedEnumerationBase
implements java.util.Enumeration
```
This class performs a preorder traversal of the tree specified by the supplied GenericTreeNode. The result is an Enumeration of FlattenedTreeNode objects. A FlattenedTreeNode is a proxy for the underlying GenericTreeNode, with one exception. If the node specified for traversal is not the root node in the larger tree, it is will appear as the root in the flattened tree node hierarchy; that is, the GenericTreeNode.getParent() method will return null for the root node supplied to the traversal. Finally, a preorder enumeration can be performed on a single root node or a "forest" of root nodes.

Since:

MicroStrategy Web 9.0.0

Field Summary
- Fields inherited from class com.microstrategy.utils.FlattenedEnumerationBase
  LOCATION_BASE_INDEX, LOCATION_SEPARATOR, locationStack, nodeStack

Constructor Summary

Constructors
Constructor	Description
`PreorderEnumeration(GenericTreeNode treeNode)`	Creates a new PreorderEnumeration object.
`PreorderEnumeration(java.util.Vector forest)`	Creates a new PreorderEnumeration object.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`boolean`	`hasMoreElements()`	Whether the enumeration has any more elements.
`java.lang.Object`	`nextElement()`	The next element in this enumeration.

Methods inherited from class com.microstrategy.utils.FlattenedEnumerationBase
getLocationEnum, isRootNode

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

Methods inherited from interface java.util.Enumeration
asIterator

- Constructor Detail
  - PreorderEnumeration
```
public PreorderEnumeration(GenericTreeNode treeNode)
```
    Creates a new PreorderEnumeration object.
    
    Parameters:
    
    treeNode - The sole, root GenericTreeNode instance that is being traversed. It and all of its children are traversed.
  - PreorderEnumeration
```
public PreorderEnumeration(java.util.Vector forest)
```
    Creates a new PreorderEnumeration object.
    
    Parameters:
    
    forest - A list of GenericTreeNode instances which form the "forest" of trees.
- Method Detail
  - hasMoreElements
```
public boolean hasMoreElements()
```
    Whether the enumeration has any more elements.
    
    Specified by:
    
    hasMoreElements in interface java.util.Enumeration
    
    Returns:
    
    True, if there are more elements to return; otherwise, false.
  - nextElement
```
public java.lang.Object nextElement()
```
    The next element in this enumeration. For this traversal, the parent node is returned before any of its children.
    
    Specified by:
    
    nextElement in interface java.util.Enumeration
    
    Returns:
    
    The next FlattenedTreeNode object in the traversal of this tree.