org.omnaest.utils.structure.hierarchy.tree
Class TreeNavigator<T extends Tree<?,TN>,TN extends TreeNode>

java.lang.Object
  org.omnaest.utils.structure.hierarchy.tree.TreeNavigator<T,TN>

Type Parameters:

T - Tree

TN - TreeNode

Direct Known Subclasses:

ObjectTreeNavigator

public class TreeNavigator<T extends Tree<?,TN>,TN extends TreeNode>
extends Object

A TreeNavigator allows to navigate on a given Tree. It will store a path to the current TreeNode, so that it can navigate in a upward direction, too.

The TreeNavigator will use an internal cache to cache the children of the selected TreeNode path. This can be turned of using #se

Author:

Omnaest

See Also:

Tree, TreeNode

Nested Class Summary

protected static class	TreeNavigator.LocalAndReducedTraversalControl Reduced TreeNavigator.TreeNodeVisitor.TraversalControl which affects the local behavior
protected class	TreeNavigator.TreeNodePathAndCache Internal representation of the path of TreeNodes.
protected class	TreeNavigator.TreeNodeTraversal<TNV extends TreeNavigator.TreeNodeVisitor<T,TN>> Includes the logic to traverse TreeNodes
static interface	TreeNavigator.TreeNodeVisitor<T extends Tree<?,TN>,TN extends TreeNode>

Field Summary

protected boolean	cachingChildrenOfPathNodes
protected boolean	navigationSuccessful
protected T	tree
protected TreeNavigator.TreeNodePathAndCache	treeNodePathAndCache Stores the current path through the TreeNodes.
protected TreeNavigator.TreeNodeTraversal<TreeNavigator.TreeNodeVisitor<T,TN>>	treeNodeTraversal

Constructor Summary

	TreeNavigator(T tree) Creates a TreeNavigator on top of the given Tree which starts with the Tree.getTreeRootNode() as navigation origin.
	TreeNavigator(T tree, boolean cachingChildrenOfPathNodes)
protected	TreeNavigator(T tree, TreeNavigator.TreeNodePathAndCache treeNodePath, boolean cachingChildrenOfPathNodes)

Method Summary

TreeNavigator<T,TN>	fork() Creates a fork instance of the current TreeNavigator.
TN	getCurrentTreeNode() Returns the current TreeNode
T	getTree()
List<TN>	getTreeNodePathList() Returns a new List instance containing the current path of TreeNodes
boolean	hasChildren() Returns true if the current TreeNode.getChildrenList() is not empty
boolean	hasNextSibling() Returns true, if the current TreeNode has a next sibling
boolean	hasParent() Returns true, if the current TreeNode has a parent
boolean	hasPreviousSibling() Returns true, if the current TreeNode has a previous sibling
boolean	isCachingChildrenOfPathNodes()
boolean	isNavigationSuccessful()
TreeNavigator<T,TN>	navigateToChildAt(int index) Tries to navigate to the child of the current TreeNode at the given index position
TreeNavigator<T,TN>	navigateToFirstChild() Navigates to the first child of the current TreeNode
TreeNavigator<T,TN>	navigateToLastChild() Navigates to the last child of the current TreeNode
TreeNavigator<T,TN>	navigateToNextSibling() Tries to navigate to the next TreeNode sibling.
TreeNavigator<T,TN>	navigateToNextSibling(int relativeIndexPosition) Tries to navigate to the next TreeNode sibling with the given relative index position.
TreeNavigator<T,TN>	navigateToParent() Navigates to the parent TreeNode
TreeNavigator<T,TN>	navigateToPreviousSibling() Tries to navigate to the direct previous sibling.
TreeNavigator<T,TN>	navigateToPreviousSibling(int relativeIndexPosition) Navigates to the previous sibling using the given relative index position decrement.
void	setCachingChildrenOfPathNodes(boolean cachingChildrenOfPathNodes)
String	toString()
TreeNavigator<T,TN>	traverse(TreeNavigator.TreeNodeVisitor.TraversalConfiguration defaultTraversalConfiguration, TreeNavigator.TreeNodeVisitor<T,TN>... treeNodeVisitors) Similar to traverse(TreeNodeVisitor...) but allows to specify a default TreeNavigator.TreeNodeVisitor.TraversalConfiguration.
TreeNavigator<T,TN>	traverse(TreeNavigator.TreeNodeVisitor.TraversalConfiguration defaultTraversalConfiguration, TreeNavigator.TreeNodeVisitor<T,TN> treeNodeVisitor) Similar to #traverse(TraversalConfiguration, TreeNodeVisitor)
TreeNavigator<T,TN>	traverse(TreeNavigator.TreeNodeVisitor<T,TN>... treeNodeVisitors) Traverses the current TreeNode and its children transitively invoking TreeNavigator.TreeNodeVisitors for each TreeNode.
TreeNavigator<T,TN>	traverse(TreeNavigator.TreeNodeVisitor<T,TN> treeNodeVisitor)

Methods inherited from class java.lang.Object

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

Field Detail

tree

protected final T extends Tree<?,TN> tree

treeNodePathAndCache

protected TreeNavigator.TreeNodePathAndCache treeNodePathAndCache

Stores the current path through the TreeNodes. The last element is the current.

navigationSuccessful

protected boolean navigationSuccessful

cachingChildrenOfPathNodes

protected boolean cachingChildrenOfPathNodes

treeNodeTraversal

protected TreeNavigator.TreeNodeTraversal<TreeNavigator.TreeNodeVisitor<T extends Tree<?,TN>,TN extends TreeNode>> treeNodeTraversal

Constructor Detail

TreeNavigator

public TreeNavigator(T tree)

Creates a TreeNavigator on top of the given Tree which starts with the Tree.getTreeRootNode() as navigation origin.

Parameters:

tree -

Throws:

IllegalArgumentException - if the Tree reference is null

See Also:

TreeNavigator, Tree, TreeNode

TreeNavigator

protected TreeNavigator(T tree,
                        TreeNavigator.TreeNodePathAndCache treeNodePath,
                        boolean cachingChildrenOfPathNodes)

Parameters:

tree -

treeNodePath -

cachingChildrenOfPathNodes -

See Also:

TreeNavigator

TreeNavigator

public TreeNavigator(T tree,
                     boolean cachingChildrenOfPathNodes)

Parameters:

tree -

cachingChildrenOfPathNodes -

See Also:

TreeNavigator

Method Detail

fork

public TreeNavigator<T,TN> fork()

Creates a fork instance of the current TreeNavigator. Any navigation actions to the fork will not affect the current TreeNavigator instance and vice versa.

Returns:

navigateToFirstChild

public TreeNavigator<T,TN> navigateToFirstChild()

Navigates to the first child of the current TreeNode

Returns:

this

navigateToLastChild

public TreeNavigator<T,TN> navigateToLastChild()

Navigates to the last child of the current TreeNode

Returns:

this

navigateToChildAt

public TreeNavigator<T,TN> navigateToChildAt(int index)

Tries to navigate to the child of the current TreeNode at the given index position

Parameters:

index -

Returns:

this

navigateToNextSibling

public TreeNavigator<T,TN> navigateToNextSibling(int relativeIndexPosition)

Tries to navigate to the next TreeNode sibling with the given relative index position. A relative index position of 0 means the current TreeNode, a relative index position of 1 means the direct next one,...

Parameters:

relativeIndexPosition -

Returns:

this

See Also:

isNavigationSuccessful(), navigateToNextSibling(), navigateToPreviousSibling(int), navigateToPreviousSibling()

navigateToNextSibling

public TreeNavigator<T,TN> navigateToNextSibling()

Tries to navigate to the next TreeNode sibling.

Returns:

this

See Also:

isNavigationSuccessful(), navigateToPreviousSibling(), navigateToNextSibling(int)

navigateToPreviousSibling

public TreeNavigator<T,TN> navigateToPreviousSibling()

Tries to navigate to the direct previous sibling.

Returns:

this

See Also:

isNavigationSuccessful(), navigateToNextSibling(int), navigateToPreviousSibling(int)

navigateToPreviousSibling

public TreeNavigator<T,TN> navigateToPreviousSibling(int relativeIndexPosition)

Navigates to the previous sibling using the given relative index position decrement. A relative index position of 0 means the current TreeNode, a relative index position of 1 means the direct previous TreeNode

Parameters:

relativeIndexPosition -

Returns:

this

See Also:

isNavigationSuccessful(), navigateToPreviousSibling(), navigateToNextSibling(), navigateToNextSibling(int)

hasNextSibling

public boolean hasNextSibling()

Returns true, if the current TreeNode has a next sibling

Returns:

hasPreviousSibling

public boolean hasPreviousSibling()

Returns true, if the current TreeNode has a previous sibling

Returns:

navigateToParent

public TreeNavigator<T,TN> navigateToParent()

Navigates to the parent TreeNode

Returns:

this

hasParent

public boolean hasParent()

Returns true, if the current TreeNode has a parent

Returns:

hasChildren

public boolean hasChildren()

Returns true if the current TreeNode.getChildrenList() is not empty

Returns:

traverse

public TreeNavigator<T,TN> traverse(TreeNavigator.TreeNodeVisitor<T,TN>... treeNodeVisitors)

Traverses the current TreeNode and its children transitively invoking TreeNavigator.TreeNodeVisitors for each TreeNode.

As default the TreeNavigator.TreeNodeVisitor.TraversalControl.GO_ON is used for the case the TreeNavigator.TreeNodeVisitor returns null.
If multiple TreeNavigator.TreeNodeVisitor instances are given and they return different TreeNavigator.TreeNodeVisitor.TraversalControl results they are grouped and a fork() is used for the different groups.

Nodes which are already visited will be excluded by default. This prevents indefinite loops related to cyclic references. To override this use TreeNavigator.TreeNodeVisitor.TraversalControl.GO_ON_INCLUDE_ALREADY_TRAVERSED_NODES in combination with #traverse(TraversalConfiguration, TreeNodeVisitor)

Parameters:

treeNodeVisitors - TreeNavigator.TreeNodeVisitor

Returns:

this

See Also:

#traverse(TraversalConfiguration, TreeNodeVisitor)

traverse

public TreeNavigator<T,TN> traverse(TreeNavigator.TreeNodeVisitor<T,TN> treeNodeVisitor)

Parameters:

treeNodeVisitor -

Returns:

See Also:

traverse(TreeNodeVisitor...)

traverse

public TreeNavigator<T,TN> traverse(TreeNavigator.TreeNodeVisitor.TraversalConfiguration defaultTraversalConfiguration,
                                    TreeNavigator.TreeNodeVisitor<T,TN> treeNodeVisitor)

Similar to #traverse(TraversalConfiguration, TreeNodeVisitor)

Parameters:

defaultTraversalConfiguration -

treeNodeVisitor -

Returns:

traverse

public TreeNavigator<T,TN> traverse(TreeNavigator.TreeNodeVisitor.TraversalConfiguration defaultTraversalConfiguration,
                                    TreeNavigator.TreeNodeVisitor<T,TN>... treeNodeVisitors)

Similar to traverse(TreeNodeVisitor...) but allows to specify a default TreeNavigator.TreeNodeVisitor.TraversalConfiguration.

The default TreeNavigator.TreeNodeVisitor.TraversalConfiguration is used initially for all TreeNavigator.TreeNodeVisitor instances. If any TreeNavigator.TreeNodeVisitor instance returns a TreeNavigator.TreeNodeVisitor.TraversalControl flag, the TreeNavigator.TreeNodeVisitor.TraversalConfiguration of the particular node is adapted while the other TreeNavigator.TreeNodeVisitor will keep their TreeNavigator.TreeNodeVisitor.TraversalConfiguration.

The TreeNavigator.TreeNodeVisitor.TraversalConfiguration defines which nodes are traversed.

Parameters:

defaultTraversalConfiguration - TreeNavigator.TreeNodeVisitor.TraversalConfiguration

treeNodeVisitors - TreeNavigator.TreeNodeVisitor

Returns:

this

See Also:

traverse(TreeNodeVisitor...)

isNavigationSuccessful

public boolean isNavigationSuccessful()

Returns:

the navigationSuccessful

getCurrentTreeNode

public TN getCurrentTreeNode()

Returns the current TreeNode

Returns:

toString

public String toString()

Overrides:

toString in class Object

isCachingChildrenOfPathNodes

public boolean isCachingChildrenOfPathNodes()

Returns:

the cachingChildrenOfPathNodes

setCachingChildrenOfPathNodes

public void setCachingChildrenOfPathNodes(boolean cachingChildrenOfPathNodes)

Parameters:

cachingChildrenOfPathNodes - the cachingChildrenOfPathNodes to set

getTree

public T getTree()

Returns:

the tree

getTreeNodePathList

public List<TN> getTreeNodePathList()

Returns a new List instance containing the current path of TreeNodes

Returns: