javax.swing.tree
Class VariableHeightLayoutCache

java.lang.Object
  javax.swing.tree.AbstractLayoutCache
      javax.swing.tree.VariableHeightLayoutCache

All Implemented Interfaces:

RowMapper

public class VariableHeightLayoutCache

extends AbstractLayoutCache

NOTE: This will become more open in a future release.

Warning: Serialized objects of this class will not be compatible with future Swing releases. The current serialization support is appropriate for short term storage or RMI between applications running the same version of Swing. As of 1.4, support for long term storage of all JavaBeans^TM has been added to the java.beans package. Please see XMLEncoder.

Author:

Rob Davis, Ray Ryan, Scott Violet

Nested Class Summary

private class	VariableHeightLayoutCache.TreeStateNode TreeStateNode is used to keep track of each of the nodes that have been expanded.
private class	VariableHeightLayoutCache.VisibleTreeStateNodeEnumeration An enumerator to iterate through visible nodes.

Nested classes inherited from class javax.swing.tree.AbstractLayoutCache

AbstractLayoutCache.NodeDimensions

Field Summary

private Rectangle	boundsBuffer Used in getting sizes for nodes to avoid creating a new Rectangle every time a size is needed.
private VariableHeightLayoutCache.TreeStateNode	root The root node of the internal cache of nodes that have been shown.
private Stack	tempStacks A stack of stacks.
private Hashtable	treePathMapping Maps from TreePath to a TreeStateNode.
private boolean	updateNodeSizes This is set to true if one of the entries has an invalid size.
private Vector	visibleNodes The array of nodes that are currently visible, in the order they are displayed.

Fields inherited from class javax.swing.tree.AbstractLayoutCache

nodeDimensions, rootVisible, rowHeight, treeModel, treeSelectionModel

Constructor Summary

VariableHeightLayoutCache()

Method Summary

private void	addMapping(VariableHeightLayoutCache.TreeStateNode node) Adds a mapping for node.
private VariableHeightLayoutCache.TreeStateNode	createNodeAt(VariableHeightLayoutCache.TreeStateNode parent, int childIndex) Creates a new node to represent the node at childIndex in parents children.
private VariableHeightLayoutCache.TreeStateNode	createNodeForValue(Object value) Responsible for creating a TreeStateNode that will be used to track display information about value.
private void	ensurePathIsExpanded(TreePath aPath, boolean expandLast) Ensures that all the path components in path are expanded, accept for the last component which will only be expanded if expandLast is true.
private Rectangle	getBounds(int row, Rectangle placeIn) Retursn the bounds for row, row by reference in placeIn.
Rectangle	getBounds(TreePath path, Rectangle placeIn) Returns the Rectangle enclosing the label portion into which the item identified by path will be drawn.
boolean	getExpandedState(TreePath path) Returns true if the path is expanded, and visible.
private VariableHeightLayoutCache.TreeStateNode	getMapping(TreePath path) Returns the node previously added for path.
private int	getMaxNodeWidth() Returns the maximum node width.
private VariableHeightLayoutCache.TreeStateNode	getNode(int row) Returns the AbstractTreeUI.VisibleNode displayed at the given row
private VariableHeightLayoutCache.TreeStateNode	getNodeForPath(TreePath path, boolean onlyIfVisible, boolean shouldCreate) Returns the TreeStateNode identified by path.
TreePath	getPathClosestTo(int x, int y) Returns the path to the node that is closest to x,y.
TreePath	getPathForRow(int row) Returns the path for row.
int	getPreferredHeight() Returns the preferred height.
int	getPreferredWidth(Rectangle bounds) Returns the preferred width and height for the region in visibleRegion.
private int	getRowContainingYLocation(int location) Returns the index of the row containing location.
int	getRowCount() Returns the number of visible rows.
int	getRowForPath(TreePath path) Returns the row where the last item identified in path is visible.
int	getVisibleChildCount(TreePath path) Returns the number of visible children for path.
Enumeration	getVisiblePathsFrom(TreePath path) Returns an Enumerator that increments over the visible paths starting at the passed in location.
void	invalidatePathBounds(TreePath path) Instructs the LayoutCache that the bounds for path are invalid, and need to be updated.
void	invalidateSizes() Informs the TreeState that it needs to recalculate all the sizes it is referencing.
boolean	isExpanded(TreePath path) Returns true if the value identified by path is currently expanded.
private void	rebuild(boolean clearSelection) Completely rebuild the tree, all expanded state, and node caches are removed.
private void	removeMapping(VariableHeightLayoutCache.TreeStateNode node) Removes the mapping for a previously added node.
void	setExpandedState(TreePath path, boolean isExpanded) Marks the path path expanded state to isExpanded.
void	setModel(TreeModel newModel) Sets the TreeModel that will provide the data.
void	setNodeDimensions(AbstractLayoutCache.NodeDimensions nd) Sets the renderer that is responsible for drawing nodes in the tree.
void	setRootVisible(boolean rootVisible) Determines whether or not the root node from the TreeModel is visible.
void	setRowHeight(int rowHeight) Sets the height of each cell.
void	treeNodesChanged(TreeModelEvent e) Invoked after a node (or a set of siblings) has changed in some way.
void	treeNodesInserted(TreeModelEvent e) Invoked after nodes have been inserted into the tree.
void	treeNodesRemoved(TreeModelEvent e) Invoked after nodes have been removed from the tree.
void	treeStructureChanged(TreeModelEvent e) Invoked after the tree has drastically changed structure from a given node down.
private void	updateNodeSizes(boolean updateAll) Resets the y origin of all the visible nodes as well as messaging all the visible nodes to updatePreferredSize().
private void	updateYLocationsFrom(int location) Updates the y locations of all of the visible nodes after location.
private void	visibleNodesChanged()

Methods inherited from class javax.swing.tree.AbstractLayoutCache

getModel, getNodeDimensions, getNodeDimensions, getRowHeight, getRowsForPaths, getSelectionModel, isFixedRowHeight, isRootVisible, setSelectionModel

Methods inherited from class java.lang.Object

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

Field Detail

visibleNodes

private Vector visibleNodes

The array of nodes that are currently visible, in the order they are displayed.

updateNodeSizes

private boolean updateNodeSizes

This is set to true if one of the entries has an invalid size.

root

private VariableHeightLayoutCache.TreeStateNode root

The root node of the internal cache of nodes that have been shown. If the treeModel is vending a network rather than a true tree, there may be one cached node for each path to a modeled node.

boundsBuffer

private Rectangle boundsBuffer

Used in getting sizes for nodes to avoid creating a new Rectangle every time a size is needed.

treePathMapping

private Hashtable treePathMapping

Maps from TreePath to a TreeStateNode.

tempStacks

private Stack tempStacks

A stack of stacks.

Constructor Detail

VariableHeightLayoutCache

public VariableHeightLayoutCache()

Method Detail

setModel

public void setModel(TreeModel newModel)

Sets the TreeModel that will provide the data.

Overrides:

setModel in class AbstractLayoutCache

Parameters:

newModel - the TreeModel that is to provide the data

setRootVisible

public void setRootVisible(boolean rootVisible)

Determines whether or not the root node from the TreeModel is visible.

Overrides:

setRootVisible in class AbstractLayoutCache

Parameters:

rootVisible - true if the root node of the tree is to be displayed

See Also:

AbstractLayoutCache.rootVisible

setRowHeight

public void setRowHeight(int rowHeight)

Sets the height of each cell. If the specified value is less than or equal to zero the current cell renderer is queried for each row's height.

Overrides:

setRowHeight in class AbstractLayoutCache

Parameters:

rowHeight - the height of each cell, in pixels

setNodeDimensions

public void setNodeDimensions(AbstractLayoutCache.NodeDimensions nd)

Sets the renderer that is responsible for drawing nodes in the tree.

Overrides:

setNodeDimensions in class AbstractLayoutCache

Parameters:

nd - the renderer

setExpandedState

public void setExpandedState(TreePath path,
                             boolean isExpanded)

Marks the path path expanded state to isExpanded.

Specified by:

setExpandedState in class AbstractLayoutCache

Parameters:

path - the TreePath of interest

isExpanded - true if the path should be expanded, otherwise false

getExpandedState

public boolean getExpandedState(TreePath path)

Returns true if the path is expanded, and visible.

Specified by:

getExpandedState in class AbstractLayoutCache

Parameters:

path - the path being queried

Returns:

true if the path is expanded and visible, otherwise false

getBounds

public Rectangle getBounds(TreePath path,
                           Rectangle placeIn)

Returns the Rectangle enclosing the label portion into which the item identified by path will be drawn.

Specified by:

getBounds in class AbstractLayoutCache

Parameters:

path - the path to be drawn

placeIn - the bounds of the enclosing rectangle

Returns:

the bounds of the enclosing rectangle or null if the node could not be ascertained

getPathForRow

public TreePath getPathForRow(int row)

Returns the path for row. If row is not visible, null is returned.

Specified by:

getPathForRow in class AbstractLayoutCache

Parameters:

row - the location of interest

Returns:

the path for row, or null if row is not visible

getRowForPath

public int getRowForPath(TreePath path)

Returns the row where the last item identified in path is visible. Will return -1 if any of the elements in path are not currently visible.

Specified by:

getRowForPath in class AbstractLayoutCache

Parameters:

path - the TreePath of interest

Returns:

the row where the last item in path is visible

getRowCount

public int getRowCount()

Returns the number of visible rows.

Specified by:

getRowCount in class AbstractLayoutCache

Returns:

the number of visible rows

invalidatePathBounds

public void invalidatePathBounds(TreePath path)

Instructs the LayoutCache that the bounds for path are invalid, and need to be updated.

Specified by:

invalidatePathBounds in class AbstractLayoutCache

Parameters:

path - the TreePath which is now invalid

getPreferredHeight

public int getPreferredHeight()

Returns the preferred height.

Overrides:

getPreferredHeight in class AbstractLayoutCache

Returns:

the preferred height

getPreferredWidth

public int getPreferredWidth(Rectangle bounds)

Returns the preferred width and height for the region in visibleRegion.

Overrides:

getPreferredWidth in class AbstractLayoutCache

Parameters:

bounds - the region being queried

Returns:

the preferred width for the passed in region

getPathClosestTo

public TreePath getPathClosestTo(int x,
                                 int y)

Returns the path to the node that is closest to x,y. If there is nothing currently visible this will return null, otherwise it will always return a valid path. If you need to test if the returned object is exactly at x, y you should get the bounds for the returned path and test x, y against that.

Specified by:

getPathClosestTo in class AbstractLayoutCache

Parameters:

x - the x-coordinate

y - the y-coordinate

Returns:

the path to the node that is closest to x, y

getVisiblePathsFrom

public Enumeration getVisiblePathsFrom(TreePath path)

Returns an Enumerator that increments over the visible paths starting at the passed in location. The ordering of the enumeration is based on how the paths are displayed.

Specified by:

getVisiblePathsFrom in class AbstractLayoutCache

Parameters:

path - the location in the TreePath to start

Returns:

an Enumerator that increments over the visible paths

getVisibleChildCount

public int getVisibleChildCount(TreePath path)

Returns the number of visible children for path.

Specified by:

getVisibleChildCount in class AbstractLayoutCache

Parameters:

path - the path being queried

Returns:

the number of visible children for path

invalidateSizes

public void invalidateSizes()

Informs the TreeState that it needs to recalculate all the sizes it is referencing.

Specified by:

invalidateSizes in class AbstractLayoutCache

isExpanded

public boolean isExpanded(TreePath path)

Returns true if the value identified by path is currently expanded.

Specified by:

isExpanded in class AbstractLayoutCache

Returns:

true if the value identified by path is currently expanded

treeNodesChanged

public void treeNodesChanged(TreeModelEvent e)

Invoked after a node (or a set of siblings) has changed in some way. The node(s) have not changed locations in the tree or altered their children arrays, but other attributes have changed and may affect presentation. Example: the name of a file has changed, but it is in the same location in the file system.

e.path returns the path the parent of the changed node(s).

e.childIndices returns the index(es) of the changed node(s).

Specified by:

treeNodesChanged in class AbstractLayoutCache

Parameters:

e - the TreeModelEvent of interest

treeNodesInserted

public void treeNodesInserted(TreeModelEvent e)

Invoked after nodes have been inserted into the tree.

e.path returns the parent of the new nodes.

e.childIndices returns the indices of the new nodes in ascending order.

Specified by:

treeNodesInserted in class AbstractLayoutCache

Parameters:

e - the TreeModelEvent of interest

treeNodesRemoved

public void treeNodesRemoved(TreeModelEvent e)

Invoked after nodes have been removed from the tree. Note that if a subtree is removed from the tree, this method may only be invoked once for the root of the removed subtree, not once for each individual set of siblings removed.

e.path returns the former parent of the deleted nodes.

e.childIndices returns the indices the nodes had before they were deleted in ascending order.

Specified by:

treeNodesRemoved in class AbstractLayoutCache

Parameters:

e - the TreeModelEvent of interest

treeStructureChanged

public void treeStructureChanged(TreeModelEvent e)

Invoked after the tree has drastically changed structure from a given node down. If the path returned by e.getPath is of length one and the first element does not identify the current root node the first element should become the new root of the tree.

e.path holds the path to the node.

e.childIndices returns null.

Specified by:

treeStructureChanged in class AbstractLayoutCache

Parameters:

e - the TreeModelEvent of interest

visibleNodesChanged

private void visibleNodesChanged()

addMapping

private void addMapping(VariableHeightLayoutCache.TreeStateNode node)

Adds a mapping for node.

removeMapping

private void removeMapping(VariableHeightLayoutCache.TreeStateNode node)

Removes the mapping for a previously added node.

getMapping

private VariableHeightLayoutCache.TreeStateNode getMapping(TreePath path)

Returns the node previously added for path. This may return null, if you to create a node use getNodeForPath.

getBounds

private Rectangle getBounds(int row,
                            Rectangle placeIn)

Retursn the bounds for row, row by reference in placeIn. If placeIn is null a new Rectangle will be created and returned.

rebuild

private void rebuild(boolean clearSelection)

Completely rebuild the tree, all expanded state, and node caches are removed. All nodes are collapsed, except the root.

createNodeAt

private VariableHeightLayoutCache.TreeStateNode createNodeAt(VariableHeightLayoutCache.TreeStateNode parent,
                                                             int childIndex)

Creates a new node to represent the node at childIndex in parents children. This should be called if the node doesn't already exist and parent has been expanded at least once. The newly created node will be made visible if parent is currently expanded. This does not update the position of any cells, nor update the selection if it needs to be. If succesful in creating the new TreeStateNode, it is returned, otherwise null is returned.

getNodeForPath

private VariableHeightLayoutCache.TreeStateNode getNodeForPath(TreePath path,
                                                               boolean onlyIfVisible,
                                                               boolean shouldCreate)

Returns the TreeStateNode identified by path. This mirrors the behavior of getNodeForPath, but tries to take advantage of path if it is an instance of AbstractTreePath.

updateYLocationsFrom

private void updateYLocationsFrom(int location)

Updates the y locations of all of the visible nodes after location.

updateNodeSizes

private void updateNodeSizes(boolean updateAll)

Resets the y origin of all the visible nodes as well as messaging all the visible nodes to updatePreferredSize(). You should not normally have to call this. Expanding and contracting the nodes automaticly adjusts the locations. updateAll determines if updatePreferredSize() is call on all nodes or just those that don't have a valid size.

getRowContainingYLocation

private int getRowContainingYLocation(int location)

Returns the index of the row containing location. If there are no rows, -1 is returned. If location is beyond the last row index, the last row index is returned.

ensurePathIsExpanded

private void ensurePathIsExpanded(TreePath aPath,
                                  boolean expandLast)

Ensures that all the path components in path are expanded, accept for the last component which will only be expanded if expandLast is true. Returns true if succesful in finding the path.

getNode

private VariableHeightLayoutCache.TreeStateNode getNode(int row)

Returns the AbstractTreeUI.VisibleNode displayed at the given row

getMaxNodeWidth

private int getMaxNodeWidth()

Returns the maximum node width.

createNodeForValue

private VariableHeightLayoutCache.TreeStateNode createNodeForValue(Object value)

Responsible for creating a TreeStateNode that will be used to track display information about value.