org.netbeans.spi.viewmodel

Interface TreeModel

All Superinterfaces:

Model

All Known Subinterfaces:

ReorderableTreeModel

All Known Implementing Classes:

CachedChildrenTreeModel, Models.CompoundModel

public interface TreeModel
extends Model

Defines data model for tree.

Field Summary

Fields

Modifier and Type	Field and Description
static String	ROOT Constant for root node.

Method Summary

Modifier and Type	Method and Description
void	addModelListener(ModelListener l) Registers given listener.
Object[]	getChildren(Object parent, int from, int to) Returns children for given parent on given indexes.
int	getChildrenCount(Object node) Returns the number of children for given node.
Object	getRoot() Returns the root node of the tree or null, if the tree is empty.
boolean	isLeaf(Object node) Returns true if node is leaf.
void	removeModelListener(ModelListener l) Unregisters given listener.

Field Detail

ROOT

static final String ROOT

Constant for root node. This root node should be used if root node does not represent any valuable information and should not be visible in tree.

See Also:

Constant Field Values

Method Detail

getRoot

Object getRoot()

Returns the root node of the tree or null, if the tree is empty.

Returns:

the root node of the tree or null

getChildren

Object[] getChildren(Object parent,
                     int from,
                     int to)
              throws UnknownTypeException

Returns children for given parent on given indexes.

This method works in pair with TreeModel.getChildrenCount(java.lang.Object), the to parameter is up to the value that is returned from TreeModel.getChildrenCount(java.lang.Object). If the list of children varies over time, the implementation code needs to pay attention to bounds and check the from and to parameters, especially if TreeModel.getChildrenCount(java.lang.Object) returns Integer.MAX_VALUE. Caching of the children between TreeModel.getChildrenCount(java.lang.Object) and TreeModel.getChildren(java.lang.Object, int, int) can be used as well, if necessary.

Parameters:

parent - a parent of returned nodes

from - a start index

to - a end index

Returns:

children for given parent on given indexes

Throws:

UnknownTypeException - if this TreeModel implementation is not able to resolve children for given node type

See Also:

TreeModel.getChildrenCount(java.lang.Object)

isLeaf

boolean isLeaf(Object node)
        throws UnknownTypeException

Returns true if node is leaf.

Returns:

true if node is leaf

Throws:

UnknownTypeException - if this TreeModel implementation is not able to resolve children for given node type

getChildrenCount

int getChildrenCount(Object node)
              throws UnknownTypeException

Returns the number of children for given node.

This method works in pair with TreeModel.getChildren(java.lang.Object, int, int), which gets this returned value (or less) as the to parameter. This method is always called before a call to TreeModel.getChildren(java.lang.Object, int, int). This method can return e.g. Integer.MAX_VALUE when all children should be loaded.

Parameters:

node - the parent node

Returns:

the children count

Throws:

UnknownTypeException - if this TreeModel implementation is not able to resolve children for given node type

Since:

1.1

See Also:

TreeModel.getChildren(java.lang.Object, int, int)

addModelListener

void addModelListener(ModelListener l)

Registers given listener.

Parameters:

l - the listener to add

removeModelListener

void removeModelListener(ModelListener l)

Unregisters given listener.

Parameters:

l - the listener to remove