OpenJDK 1.22 · javax.swing.tree.TreePath

TreePath represents an array of objects that uniquely identify the path to a node in a tree. The elements of the array are ordered with the root as the first element of the array. For example, a file on the file system is uniquely identified based on the array of parent directories and the name of the file. The path /tmp/foo/bar could be represented by a TreePath as new TreePath(new Object[] {"tmp", "foo", "bar"}).

TreePath is used extensively by JTree and related classes. For example, JTree represents the selection as an array of TreePaths. When used with JTree, the elements of the path are the objects returned from the TreeModel. When JTree is paired with DefaultTreeModel, the elements of the path are TreeNodes. The following example illustrates extracting the user object from the selection of a JTree:

  DefaultMutableTreeNode root = ...;
  DefaultTreeModel model = new DefaultTreeModel(root);
  JTree tree = new JTree(model);
  ...
  TreePath selectedPath = tree.getSelectionPath();
  DefaultMutableTreeNode selectedNode =
      ((DefaultMutableTreeNode)selectedPath.getLastPathComponent());
  Object myObject= selectedNode.getUserObject();

Subclasses typically need override only getLastPathComponent, and getParentPath. As JTree internally creates TreePaths at various points, it's generally not useful to subclass TreePath and use with JTree.

While TreePath is serializable, a NotSerializableException is thrown if any elements of the path are not serializable.

For further information and examples of using tree paths, see How to Use Trees in The Java Tutorial.

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 has been added to the java.beans package. Please see java.beans.XMLEncoder.

Modifier and Type	Field and Description
private Object	lastPathComponent Last path component.
private TreePath	parentPath Path representing the parent, null if lastPathComponent represents the root.

Constructor Summary

Access	Constructor and Description
public	TreePath(Object[] an array of objects representing the path to a node path) Creates a `TreePath` from an array.
public	TreePath(Object the root lastPathComponent) Creates a `TreePath` containing a single element.
protected	TreePath(TreePath the path to the parent, or `null` to indicate the root parent, Object the last path element lastPathComponent) Creates a `TreePath` with the specified parent and element.
protected	TreePath(Object[] the array to create the `TreePath` from path, int identifies the number of elements in `path` to create the `TreePath` from length) Creates a `TreePath` from an array.
protected	TreePath() Creates an empty `TreePath`.

Method Summary

Modifier and Type	Method and Description
public boolean	equals(Object the object to compare o) Overrides java.lang.Object.equals. Compares this `TreePath` to the specified object.
public Object	Returns: the last element in the path getLastPathComponent() Returns the last element of this path.
public TreePath	Returns: the parent path getParentPath() Returns the `TreePath` of the parent.
public Object[]	Returns: an array of the elements in this `TreePath` getPath() Returns an ordered array of the elements of this `TreePath`.
public Object	Returns: the element at the specified index getPathComponent(int the index of the element requested index) Returns the path element at the specified index.
public int	Returns: the number of elements in the path getPathCount() Returns the number of elements in the path.
public int	Returns: the hashCode for the object hashCode() Overrides java.lang.Object.hashCode. Returns the hash code of this `TreePath`.
public boolean	Returns: true if `aTreePath` is a descendant of this path isDescendant(TreePath the `TreePath` to check aTreePath) Returns true if `aTreePath` is a descendant of this `TreePath`.
public TreePath	Returns: a new path containing all the elements of this path plus `child` pathByAddingChild(Object the path element to add child) Returns a new path containing all the elements of this path plus `child`.
public String	Returns: a String representation of this object toString() Overrides java.lang.Object.toString. Returns a string that displays and identifies this object's properties.

Inherited from java.lang.Object:: clone finalize getClass notify notifyAll wait wait wait

Field Detail

lastPathComponent	back to summary
private Object lastPathComponent Last path component.

parentPath	back to summary
private TreePath parentPath Path representing the parent, null if lastPathComponent represents the root.

Constructor Detail

TreePath back to summary

TreePath	back to summary
public TreePath(Object[] path) Creates a `TreePath` from an array. The array uniquely identifies the path to a node. Parameters path:Object[] an array of objects representing the path to a node Annotations @ConstructorProperties:path Exceptions IllegalArgumentException: if `path` is `null`, empty, or contains a `null` value

public TreePath(Object[] path)

Creates a TreePath from an array. The array uniquely identifies the path to a node.

Parameters

path:Object[]: an array of objects representing the path to a node

Annotations

@ConstructorProperties:path

Exceptions

IllegalArgumentException:: if path is null, empty, or contains a null value

TreePath back to summary

TreePath	back to summary
public TreePath(Object lastPathComponent) Creates a `TreePath` containing a single element. This is used to construct a `TreePath` identifying the root. Parameters lastPathComponent:Object the root Exceptions IllegalArgumentException: if `lastPathComponent` is `null` See Also `TreePath(Object[])`

public TreePath(Object lastPathComponent)

Creates a TreePath containing a single element. This is used to construct a TreePath identifying the root.

Parameters

lastPathComponent:Object: the root

Exceptions

IllegalArgumentException:: if lastPathComponent is null

See Also

TreePath(Object[])

TreePath back to summary

TreePath	back to summary
protected TreePath(TreePath parent, Object lastPathComponent) Creates a `TreePath` with the specified parent and element. Parameters parent:TreePath the path to the parent, or `null` to indicate the root lastPathComponent:Object the last path element Exceptions IllegalArgumentException: if `lastPathComponent` is `null`

protected TreePath(TreePath parent, Object lastPathComponent)

Creates a TreePath with the specified parent and element.

Parameters

parent:TreePath: the path to the parent, or null to indicate the root
lastPathComponent:Object: the last path element

Exceptions

IllegalArgumentException:: if lastPathComponent is null

TreePath back to summary

TreePath	back to summary
protected TreePath(Object[] path, int length) Creates a `TreePath` from an array. The returned `TreePath` represents the elements of the array from `0` to `length - 1`. This constructor is used internally, and generally not useful outside of subclasses. Parameters path:Object[] the array to create the `TreePath` from length:int identifies the number of elements in `path` to create the `TreePath` from Exceptions NullPointerException: if `path` is `null` ArrayIndexOutOfBoundsException: if `length - 1` is outside the range of the array IllegalArgumentException: if any of the elements from `0` to `length - 1` are `null`

protected TreePath(Object[] path, int length)

Creates a TreePath from an array. The returned TreePath represents the elements of the array from 0 to length - 1.

This constructor is used internally, and generally not useful outside of subclasses.

Parameters

path:Object[]: the array to create the TreePath from
length:int: identifies the number of elements in path to create the TreePath from

Exceptions

NullPointerException:: if path is null
ArrayIndexOutOfBoundsException:: if length - 1 is outside the range of the array
IllegalArgumentException:: if any of the elements from 0 to length - 1 are null

TreePath	back to summary
protected TreePath() Creates an empty `TreePath`. This is provided for subclasses that represent paths in a different manner. Subclasses that use this constructor must override `getLastPathComponent`, and `getParentPath`.

Method Detail

equals back to summary

equals	back to summary
public boolean equals(Object o) Overrides java.lang.Object.equals. Compares this `TreePath` to the specified object. This returns `true` if `o` is a `TreePath` with the exact same elements (as determined by using `equals` on each element of the path). Parameters o:Object the object to compare Returns:boolean Doc from java.lang.Object.equals. `true` if this object is the same as the obj argument; `false` otherwise.

public boolean equals(Object o)

Overrides java.lang.Object.equals.

Compares this TreePath to the specified object. This returns true if o is a TreePath with the exact same elements (as determined by using equals on each element of the path).

Parameters

o:Object: the object to compare

Returns:boolean

Doc from java.lang.Object.equals.

true if this object is the same as the obj argument; false otherwise.

getLastPathComponent	back to summary
public Object getLastPathComponent() Returns the last element of this path. Returns:Object the last element in the path

getLastPathComponent

back to summary

public Object getLastPathComponent()

Returns the last element of this path.

Returns:Object: the last element in the path

getParentPath back to summary

getParentPath	back to summary
public TreePath getParentPath() Returns the `TreePath` of the parent. A return value of `null` indicates this is the root node. Returns:TreePath the parent path

public TreePath getParentPath()

Returns the TreePath of the parent. A return value of null indicates this is the root node.

Returns:TreePath: the parent path

getPath back to summary

getPath	back to summary
public Object[] getPath() Returns an ordered array of the elements of this `TreePath`. The first element is the root. Returns:Object[] an array of the elements in this `TreePath`

public Object[] getPath()

Returns an ordered array of the elements of this TreePath. The first element is the root.

Returns:Object[]: an array of the elements in this TreePath

getPathComponent	back to summary
public Object getPathComponent(int index) Returns the path element at the specified index. Parameters index:int the index of the element requested Returns:Object the element at the specified index Exceptions IllegalArgumentException: if the index is outside the range of this path

getPathComponent

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public Object getPathComponent(int index)

Returns the path element at the specified index.

Parameters

index:int: the index of the element requested

Returns:Object

the element at the specified index

Exceptions

IllegalArgumentException:: if the index is outside the range of this path

getPathCount	back to summary
public int getPathCount() Returns the number of elements in the path. Returns:int the number of elements in the path

getPathCount

back to summary

public int getPathCount()

Returns the number of elements in the path.

Returns:int: the number of elements in the path

hashCode back to summary

hashCode	back to summary
public int hashCode() Overrides java.lang.Object.hashCode. Returns the hash code of this `TreePath`. The hash code of a `TreePath` is the hash code of the last element in the path. Returns:int the hashCode for the object

public int hashCode()

Overrides java.lang.Object.hashCode.

Returns the hash code of this TreePath. The hash code of a TreePath is the hash code of the last element in the path.

Returns:int: the hashCode for the object

isDescendant back to summary

isDescendant	back to summary
public boolean isDescendant(TreePath aTreePath) Returns true if `aTreePath` is a descendant of this `TreePath`. A `TreePath` `P1` is a descendant of a `TreePath` `P2` if `P1` contains all of the elements that make up `P2's` path. For example, if this object has the path `[a, b]`, and `aTreePath` has the path `[a, b, c]`, then `aTreePath` is a descendant of this object. However, if `aTreePath` has the path `[a]`, then it is not a descendant of this object. By this definition a `TreePath` is always considered a descendant of itself. That is, `aTreePath.isDescendant(aTreePath)` returns `true`. Parameters aTreePath:TreePath the `TreePath` to check Returns:boolean true if `aTreePath` is a descendant of this path

public boolean isDescendant(TreePath aTreePath)

Returns true if aTreePath is a descendant of this TreePath. A TreePath P1 is a descendant of a TreePath P2 if P1 contains all of the elements that make up P2's path. For example, if this object has the path [a, b], and aTreePath has the path [a, b, c], then aTreePath is a descendant of this object. However, if aTreePath has the path [a], then it is not a descendant of this object. By this definition a TreePath is always considered a descendant of itself. That is, aTreePath.isDescendant(aTreePath) returns true.

Parameters

aTreePath:TreePath: the TreePath to check

Returns:boolean

true if aTreePath is a descendant of this path

pathByAddingChild back to summary

pathByAddingChild	back to summary
public TreePath pathByAddingChild(Object child) Returns a new path containing all the elements of this path plus `child`. `child` is the last element of the newly created `TreePath`. Parameters child:Object the path element to add Returns:TreePath a new path containing all the elements of this path plus `child` Exceptions NullPointerException: if `child` is `null`

public TreePath pathByAddingChild(Object child)

Returns a new path containing all the elements of this path plus child. child is the last element of the newly created TreePath.

Parameters

child:Object: the path element to add

Returns:TreePath

a new path containing all the elements of this path plus child

Exceptions

NullPointerException:: if child is null

toString	back to summary
public String toString() Overrides java.lang.Object.toString. Returns a string that displays and identifies this object's properties. Returns:String a String representation of this object

toString

back to summary

public String toString()

Overrides java.lang.Object.toString.

Returns a string that displays and identifies this object's properties.

Returns:String: a String representation of this object

public Class TreePath

Field Summary

Constructor Summary

Method Summary

Field Detail

Constructor Detail

Method Detail