java.beans package.
* Please see {@link java.beans.XMLEncoder}.
*
* @author Scott Violet
*/
@SuppressWarnings("serial") // Same-version serialization only
public abstract class AbstractLayoutCache implements RowMapper {
/** Object responsible for getting the size of a node. */
protected NodeDimensions nodeDimensions;
/** Model providing information. */
protected TreeModel treeModel;
/** Selection model. */
protected TreeSelectionModel treeSelectionModel;
/**
* True if the root node is displayed, false if its children are
* the highest visible nodes.
*/
protected boolean rootVisible;
/**
* Height to use for each row. If this is <= 0 the renderer will be
* used to determine the height for each row.
*/
protected int rowHeight;
/**
* Sets the renderer that is responsible for drawing nodes in the tree
* and which is therefore responsible for calculating the dimensions of
* individual nodes.
*
* @param nd a NodeDimensions object
*/
public void setNodeDimensions(NodeDimensions nd) {
this.nodeDimensions = nd;
}
/**
* Returns the object that renders nodes in the tree, and which is
* responsible for calculating the dimensions of individual nodes.
*
* @return the NodeDimensions object
*/
public NodeDimensions getNodeDimensions() {
return nodeDimensions;
}
/**
* Sets the TreeModel that will provide the data.
*
* @param newModel the TreeModel that is to
* provide the data
*/
public void setModel(TreeModel newModel) {
treeModel = newModel;
}
/**
* Returns the TreeModel that is providing the data.
*
* @return the TreeModel that is providing the data
*/
public TreeModel getModel() {
return treeModel;
}
/**
* Determines whether or not the root node from
* the TreeModel is visible.
*
* @param rootVisible true if the root node of the tree is to be displayed
* @see #rootVisible
* @beaninfo
* bound: true
* description: Whether or not the root node
* from the TreeModel is visible.
*/
public void setRootVisible(boolean rootVisible) {
this.rootVisible = rootVisible;
}
/**
* Returns true if the root node of the tree is displayed.
*
* @return true if the root node of the tree is displayed
* @see #rootVisible
*/
public boolean isRootVisible() {
return rootVisible;
}
/**
* 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.
*
* @param rowHeight the height of each cell, in pixels
* @beaninfo
* bound: true
* description: The height of each cell.
*/
public void setRowHeight(int rowHeight) {
this.rowHeight = rowHeight;
}
/**
* Returns the height of each row. If the returned value is less than
* or equal to 0 the height for each row is determined by the
* renderer.
*/
public int getRowHeight() {
return rowHeight;
}
/**
* Sets the TreeSelectionModel used to manage the
* selection to new LSM.
*
* @param newLSM the new TreeSelectionModel
*/
public void setSelectionModel(TreeSelectionModel newLSM) {
if(treeSelectionModel != null)
treeSelectionModel.setRowMapper(null);
treeSelectionModel = newLSM;
if(treeSelectionModel != null)
treeSelectionModel.setRowMapper(this);
}
/**
* Returns the model used to maintain the selection.
*
* @return the treeSelectionModel
*/
public TreeSelectionModel getSelectionModel() {
return treeSelectionModel;
}
/**
* Returns the preferred height.
*
* @return the preferred height
*/
public int getPreferredHeight() {
// Get the height
int rowCount = getRowCount();
if(rowCount > 0) {
Rectangle bounds = getBounds(getPathForRow(rowCount - 1),
null);
if(bounds != null)
return bounds.y + bounds.height;
}
return 0;
}
/**
* Returns the preferred width for the passed in region.
* The region is defined by the path closest to
* (bounds.x, bounds.y) and
* ends at bounds.height + bounds.y.
* If bounds is null,
* the preferred width for all the nodes
* will be returned (and this may be a VERY expensive
* computation).
*
* @param bounds the region being queried
* @return the preferred width for the passed in region
*/
public int getPreferredWidth(Rectangle bounds) {
int rowCount = getRowCount();
if(rowCount > 0) {
// Get the width
TreePath firstPath;
int endY;
if(bounds == null) {
firstPath = getPathForRow(0);
endY = Integer.MAX_VALUE;
}
else {
firstPath = getPathClosestTo(bounds.x, bounds.y);
endY = bounds.height + bounds.y;
}
Enumeration paths = getVisiblePathsFrom(firstPath);
if(paths != null && paths.hasMoreElements()) {
Rectangle pBounds = getBounds((TreePath)paths.nextElement(),
null);
int width;
if(pBounds != null) {
width = pBounds.x + pBounds.width;
if (pBounds.y >= endY) {
return width;
}
}
else
width = 0;
while (pBounds != null && paths.hasMoreElements()) {
pBounds = getBounds((TreePath)paths.nextElement(),
pBounds);
if (pBounds != null && pBounds.y < endY) {
width = Math.max(width, pBounds.x + pBounds.width);
}
else {
pBounds = null;
}
}
return width;
}
}
return 0;
}
//
// Abstract methods that must be implemented to be concrete.
//
/**
* Returns true if the value identified by row is currently expanded.
*/
public abstract boolean isExpanded(TreePath path);
/**
* Returns a rectangle giving the bounds needed to draw path.
*
* @param path a TreePath specifying a node
* @param placeIn a Rectangle object giving the
* available space
* @return a Rectangle object specifying the space to be used
*/
public abstract Rectangle getBounds(TreePath path, Rectangle placeIn);
/**
* Returns the path for passed in row. If row is not visible
* null is returned.
*
* @param row the row being queried
* @return the TreePath for the given row
*/
public abstract TreePath getPathForRow(int row);
/**
* Returns the row that the last item identified in path is visible
* at. Will return -1 if any of the elements in path are not
* currently visible.
*
* @param path the TreePath being queried
* @return the row where the last item in path is visible or -1
* if any elements in path aren't currently visible
*/
public abstract int getRowForPath(TreePath path);
/**
* Returns the path to the node that is closest to x,y. If
* there is nothing currently visible this will return null,
* otherwise it'll 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.
*
* @param x the horizontal component of the desired location
* @param y the vertical component of the desired location
* @return the TreePath closest to the specified point
*/
public abstract TreePath getPathClosestTo(int x, int y);
/**
* 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.
* The first element of the returned enumeration will be path,
* unless it isn't visible,
* in which case null will be returned.
*
* @param path the starting location for the enumeration
* @return the Enumerator starting at the desired location
*/
public abstract Enumerationpath expanded state to
* isExpanded.
*
* @param path the path being expanded or collapsed
* @param isExpanded true if the path should be expanded, false otherwise
*/
public abstract void setExpandedState(TreePath path, boolean isExpanded);
/**
* Returns true if the path is expanded, and visible.
*
* @param path the path being queried
* @return true if the path is expanded and visible, false otherwise
*/
public abstract boolean getExpandedState(TreePath path);
/**
* Number of rows being displayed.
*
* @return the number of rows being displayed
*/
public abstract int getRowCount();
/**
* Informs the TreeState that it needs to recalculate
* all the sizes it is referencing.
*/
public abstract void invalidateSizes();
/**
* Instructs the LayoutCache that the bounds for
* path are invalid, and need to be updated.
*
* @param path the path being updated
*/
public abstract void invalidatePathBounds(TreePath path);
//
// TreeModelListener methods
// AbstractTreeState does not directly become a TreeModelListener on
// the model, it is up to some other object to forward these methods.
//
/**
* * 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).
* * @param e theTreeModelEvent
*/
public abstract void treeNodesChanged(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.
* * @param e theTreeModelEvent
*/
public abstract void treeNodesInserted(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.
* * @param e theTreeModelEvent
*/
public abstract void treeNodesRemoved(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.
* * @param e theTreeModelEvent
*/
public abstract void treeStructureChanged(TreeModelEvent e);
//
// RowMapper
//
/**
* Returns the rows that the TreePath instances in
* path are being displayed at.
* This method should return an array of the same length as that passed
* in, and if one of the TreePaths
* in path is not valid its entry in the array should
* be set to -1.
*
* @param paths the array of TreePaths being queried
* @return an array of the same length that is passed in containing
* the rows that each corresponding where each
* TreePath is displayed; if paths
* is null, null is returned
*/
public int[] getRowsForPaths(TreePath[] paths) {
if(paths == null)
return null;
int numPaths = paths.length;
int[] rows = new int[numPaths];
for(int counter = 0; counter < numPaths; counter++)
rows[counter] = getRowForPath(paths[counter]);
return rows;
}
//
// Local methods that subclassers may wish to use that are primarly
// convenience methods.
//
/**
* Returns, by reference in placeIn,
* the size needed to represent value.
* If inPlace is null, a newly created
* Rectangle should be returned, otherwise the value
* should be placed in inPlace and returned. This will
* return null if there is no renderer.
*
* @param value the value to be represented
* @param row row being queried
* @param depth the depth of the row
* @param expanded true if row is expanded, false otherwise
* @param placeIn a Rectangle containing the size needed
* to represent value
* @return a Rectangle containing the node dimensions,
* or null if node has no dimension
*/
protected Rectangle getNodeDimensions(Object value, int row, int depth,
boolean expanded,
Rectangle placeIn) {
NodeDimensions nd = getNodeDimensions();
if(nd != null) {
return nd.getNodeDimensions(value, row, depth, expanded, placeIn);
}
return null;
}
/**
* Returns true if the height of each row is a fixed size.
*/
protected boolean isFixedRowHeight() {
return (rowHeight > 0);
}
/**
* Used by AbstractLayoutCache to determine the size
* and x origin of a particular node.
*/
static public abstract class NodeDimensions {
/**
* Returns, by reference in bounds, the size and x origin to
* place value at. The calling method is responsible for determining
* the Y location. If bounds is null, a newly created
* Rectangle should be returned,
* otherwise the value should be placed in bounds and returned.
*
* @param value the value to be represented
* @param row row being queried
* @param depth the depth of the row
* @param expanded true if row is expanded, false otherwise
* @param bounds a Rectangle containing the size needed
* to represent value
* @return a Rectangle containing the node dimensions,
* or null if node has no dimension
*/
public abstract Rectangle getNodeDimensions(Object value, int row,
int depth,
boolean expanded,
Rectangle bounds);
}
}