Methods in TreeIterator Interface

 

 

TreeIterator Interface

boolean

addRoot (Object item)

Adds the specified item as the root of this tree.  Throws an exception if the item is null or the tree in nonempty, else return true.  The current node equals the root, and there is no current parent.

boolean

addFirstChild (Object item)

Adds the specified item as the first child of the current node.  Throws an exception if the item is null or if there is no current node, else returns true.  The current parent now equals the old current node, and the current node now equals the new node.

boolean

addRightSibling (Object item)

Adds the specified item as the right sibling of the current node.  Throws an exception if the item is null or if there is no current node or if the root is current, else returns true. The current parent does not change, and the current node now equals the new node.

Object

getCurrent ()

Returns the item in the current node or null if there is no current node.

Object

getFirstChild ()

If there is no current node then

    returns null

Else

    current parent = current node

    returns item in first child or null if there is none

    current node = first child or undefined if there is none

Endif

Object

getParent ()

If there is no current parent then

    returns null

Else

    returns item in current parent

    current node = current parent

    current parent = current node's parent or undefined if now at root

Endif

Object

getRightSibling ()

If there is no current node then

    returns null

Else

    returns item in right sibling or null if there is none

    current node = right sibling or undefined if there is none

Endif

Object

getRoot ()

Returns the item in the root or null if the tree is empty.

boolean

hasChild ()

Returns true if the current node has a child else false.  Throws an exception if there is no current node.

boolean

hasCurrentPosition ()

Returns true if there is a current node.

boolean

hasParent ()

Returns true if there is a current parent

boolean

hasRightSibling ()

Returns true if the current node has a right sibling.  Throws an exception if there is no current node.

boolean

moveTo (int index[])

If the index is invalid then

    returns true

    current node = specified node

    current parent = current node's parent or undefined if there is none

Else

    returns false

    current node and current parent are now undefined

Else

boolean

moveTo (Object item)

If the item is null then

    throws an exception

Else if the item is not found then

    returns false

    current node and current parent are now undefined

Else

    returns true

    current node = first node in preorder traversal that contains specified item

    current parent = current node's parent or undefined if there is none

End

Object

removeCurrent ()

If there is no current node then

    throws an exception

Else

    returns item in current node

    removes current node and its children

    current node = current node's right sibling or undefined if there is none

Endif   

Object

setCurrent (Object item)

Returns the item in the current node and sets the content of the current node to the specified item.  Throws an exception if the specified item is null or if there is no current node.

 

martin@cc.wwu.edu
Disclaimer

Copyright Martin Osborne 1998-2001
  All rights reserved