Tree

Type Parameters:

E - the type of elements in this tree

All Superinterfaces:

java.util.Collection<E>, java.lang.Iterable<E>

All Known Implementing Classes:

AbstractTree, BinaryTree, OrderedTree, UnorderedTree
```
public interface Tree<E>
extends java.util.Collection<E>
```
An interface for a general-purpose tree and a node.

Author:

Jun Araki

Method Summary

All Methods Instance Methods Abstract Methods
Modifier and Type	Method and Description
`void`	`addChild(E element)` Adds a child with the given element to this node.
`int`	`degree()` Returns the degree of this tree.
`int`	`degree(Tree<E> node)` Returns the degree of the given node.
`int`	`depth()` Returns the depth of this tree.
`int`	`depth(Tree<E> node)` Returns the depth of the given node.
`boolean`	`equals(java.lang.Object obj)` Returns `true` if the given object is equal to this tree.
`Tree<E>`	`find(E element)` Finds a node of the first occurrence of the given element in this tree.
`Tree<E>`	`findChild(E element)` Finds a child of the first occurrence of the given element in this node.
`java.util.List<E>`	`getAncestorElements()` Returns a list of elements of ancestors of this node, ordered from the root to the parent of this node.
`E`	`getElement()` Returns the element of this node.
`java.util.List<E>`	`getElements()` Returns a list of all elements of this tree.
`java.util.List<Tree<E>>`	`getNodes()` Returns a list of all nodes of this tree.
`Tree<E>`	`getParent()` Returns the parent of this node.
`Tree<E>`	`getRoot()` Returns the root of this tree.
`java.util.Collection<E>`	`getSiblingElements()` Returns a collection of elements of siblings of this node.
`boolean`	`hasAncestor(E element)` Returns `true` if this node has an ancestor with the given element.
`boolean`	`hasAncestor(Tree<E> ancestor)` Returns `true` if this node has the given ancestor.
`boolean`	`hasChild()` Returns `true` if this node has a child.
`boolean`	`hasChild(E element)` Returns `true` if this node has a child with the given element.
`boolean`	`hasDescendant(E element)` Returns `true` if this node has a descendant with the given element.
`boolean`	`hasDescendant(Tree<E> descendant)` Returns `true` if this node has the given descendant.
`boolean`	`hasElement()` Returns `true` if this node has an element.
`boolean`	`hasElement(E element)` Returns `true` if this node has the given element.
`int`	`hashCode()` Returns the hash code value for this tree.
`boolean`	`hasParent()` Returns `true` if this node has a parent.
`boolean`	`hasParent(E element)` Returns `true` if this node has a parent with the given element.
`boolean`	`hasParent(Tree<E> parent)` Returns `true` if this node has the given parent.
`boolean`	`isBalanced()` Returns `true` if this tree is balanced.
`boolean`	`isLabeled()` Returns `true` if this node is labeled.
`boolean`	`isLabeledTree(java.util.Set<E> alphabet)` Returns `true` if this tree is a labeled tree.
`boolean`	`isLeaf()` Returns `true` if this node is a leaf.
`boolean`	`isRoot()` Returns `true` if this node is the root.
`int`	`numChildren()` Returns the number of children of this node.
`int`	`numLeaves()` Returns the number of leaves in this tree.
`int`	`numSiblings()` Returns the number of siblings of this node.
`void`	`remove()` Removes this node.
`void`	`removeChild(E element)` Removes a child with the given element from this node.
`void`	`removeChildren()` Removes all children from this node.
`void`	`removeChildren(java.util.Collection<E> element)` Removes children with one of the given elements from this node.
`void`	`setElement(E element)` Sets the given element to this node.
`java.util.List<E>`	`yield()` Returns the yield of this tree as a list of elements of leaves.

Methods inherited from interface java.util.Collection
add, addAll, clear, contains, containsAll, isEmpty, iterator, parallelStream, remove, removeAll, removeIf, retainAll, size, spliterator, stream, toArray, toArray

Methods inherited from interface java.lang.Iterable
forEach

- Method Detail
  - equals
```
boolean equals(java.lang.Object obj)
```
    Returns true if the given object is equal to this tree.
    
    Specified by:
    
    equals in interface java.util.Collection<E>
    
    Overrides:
    
    equals in class java.lang.Object
    
    Parameters:
    
    obj - an object to be compared with this tree
    
    Returns:
    
    true if the given object is equal to this tree; false otherwise
  - hashCode
```
int hashCode()
```
    Returns the hash code value for this tree.
    
    Specified by:
    
    hashCode in interface java.util.Collection<E>
    
    Overrides:
    
    hashCode in class java.lang.Object
    
    Returns:
    
    the hash code value for this tree
  - find
```
Tree<E> find(E element)
```
    Finds a node of the first occurrence of the given element in this tree.
    
    Parameters:
    
    element - an element to be found in this tree, if present
    
    Returns:
    
    a node of the first occurrence of the given element in this tree
  - findChild
```
Tree<E> findChild(E element)
```
    Finds a child of the first occurrence of the given element in this node.
    
    Parameters:
    
    element - an element to be found in the children of this node, if present
    
    Returns:
    
    a child of the first occurrence of the given element in this node
  - depth
```
int depth()
```
    Returns the depth of this tree. The depth of a tree is defined as the maximum depth of a node in the tree.
    
    Returns:
    
    the depth of this tree
  - depth
```
int depth(Tree<E> node)
```
    Returns the depth of the given node. The depth of a node is defined as the number edges on the path from the node to this node (as the root). Returns -1 if this node is not an ancestor of the given node.
    
    Parameters:
    
    node - a node whose depth will be returned
    
    Returns:
    
    the depth of the given node
  - getParent
```
Tree<E> getParent()
```
    Returns the parent of this node.
    
    Returns:
    
    the parent of this node
  - hasParent
```
boolean hasParent()
```
    Returns true if this node has a parent.
    
    Returns:
    
    true if this node has a parent; false otherwise
  - hasParent
```
boolean hasParent(E element)
```
    Returns true if this node has a parent with the given element.
    
    Parameters:
    
    element - an element whose presence in the parent of this node will be tested
    
    Returns:
    
    true if this node has a parent with the given element; false otherwise
  - hasParent
```
boolean hasParent(Tree<E> parent)
```
    Returns true if this node has the given parent.
    
    Parameters:
    
    parent - a parent whose presence in this node will be tested
    
    Returns:
    
    true if this node has the given parent; false otherwise
  - degree
```
int degree()
```
    Returns the degree of this tree. The degree of a tree is defined as the maximum degree of a node in the tree.
    
    Returns:
    
    the degree of this tree
  - degree
```
int degree(Tree<E> node)
```
    Returns the degree of the given node. The degree of a node is defined as the number of children of the node.
    
    Parameters:
    
    node - a node whose degree will be returned
    
    Returns:
    
    the degree of the given node
  - numChildren
```
int numChildren()
```
    Returns the number of children of this node.
    
    Returns:
    
    the number of children of this node
  - hasChild
```
boolean hasChild()
```
    Returns true if this node has a child.
    
    Returns:
    
    true if this node has a child; false otherwise
  - hasChild
```
boolean hasChild(E element)
```
    Returns true if this node has a child with the given element.
    
    Parameters:
    
    element - an element whose presence in the children of this node will be tested
    
    Returns:
    
    true if this node has a child with the given element; false otherwise
  - addChild
```
void addChild(E element)
```
    Adds a child with the given element to this node.
    
    Parameters:
    
    element - an element that will be added to the children of this node
  - getSiblingElements
```
java.util.Collection<E> getSiblingElements()
```
    Returns a collection of elements of siblings of this node.
    
    Returns:
    
    a collection of elements of siblings of this node
  - numSiblings
```
int numSiblings()
```
    Returns the number of siblings of this node.
    
    Returns:
    
    the number of siblings of this node
  - getRoot
```
Tree<E> getRoot()
```
    Returns the root of this tree.
    
    Returns:
    
    the root of this tree
  - isRoot
```
boolean isRoot()
```
    Returns true if this node is the root.
    
    Returns:
    
    true if this node is the root; false otherwise
  - getAncestorElements
```
java.util.List<E> getAncestorElements()
```
    Returns a list of elements of ancestors of this node, ordered from the root to the parent of this node.
    
    Returns:
    
    a list of elements of ancestors of this node, ordered from the root to the parent of this node
  - remove
```
void remove()
```
    Removes this node.
  - removeChild
```
void removeChild(E element)
```
    Removes a child with the given element from this node. This operation removes the child and its all descendants.
    
    Parameters:
    
    element - an element to be removed from the children of this node
  - removeChildren
```
void removeChildren()
```
    Removes all children from this node.
  - removeChildren
```
void removeChildren(java.util.Collection<E> element)
```
    Removes children with one of the given elements from this node. This operation removes the children and their all descendants.
    
    Parameters:
    
    element - a collection of elements to be removed from the children of this node
  - hasAncestor
```
boolean hasAncestor(E element)
```
    Returns true if this node has an ancestor with the given element.
    
    Parameters:
    
    element - an element whose presence in the ancestors of this node will be tested
    
    Returns:
    
    true if this node has the given ancestor; false otherwise
  - hasAncestor
```
boolean hasAncestor(Tree<E> ancestor)
```
    Returns true if this node has the given ancestor.
    
    Parameters:
    
    ancestor - an ancestor whose presence for this node will be tested
    
    Returns:
    
    true if this node has the given ancestor; false otherwise
  - hasDescendant
```
boolean hasDescendant(E element)
```
    Returns true if this node has a descendant with the given element.
    
    Parameters:
    
    element - an element whose presence in the descendants of this node will be tested
    
    Returns:
    
    true if this node has the given descendant; false otherwise
  - hasDescendant
```
boolean hasDescendant(Tree<E> descendant)
```
    Returns true if this node has the given descendant.
    
    Parameters:
    
    descendant - a descendant whose presence for this node will be tested
    
    Returns:
    
    true if this node has the given descendant; false otherwise
  - getElements
```
java.util.List<E> getElements()
```
    Returns a list of all elements of this tree.
    
    Returns:
    
    a list of all elements of this tree
  - getNodes
```
java.util.List<Tree<E>> getNodes()
```
    Returns a list of all nodes of this tree.
    
    Returns:
    
    a list of all nodes of this tree
  - isLeaf
```
boolean isLeaf()
```
    Returns true if this node is a leaf.
    
    Returns:
    
    true if this node is a leaf; false otherwise
  - numLeaves
```
int numLeaves()
```
    Returns the number of leaves in this tree.
    
    Returns:
    
    the number of leaves in this tree
  - getElement
```
E getElement()
```
    Returns the element of this node.
    
    Returns:
    
    the element of this node
  - setElement
```
void setElement(E element)
```
    Sets the given element to this node.
    
    Parameters:
    
    element - an element that will be set to this node
  - hasElement
```
boolean hasElement()
```
    Returns true if this node has an element.
    
    Returns:
    
    true if this node has an element; false otherwise
  - hasElement
```
boolean hasElement(E element)
```
    Returns true if this node has the given element.
    
    Parameters:
    
    element - an element whose presence in this node will be tested
    
    Returns:
    
    true if this node has the given element; false otherwise
  - isLabeled
```
boolean isLabeled()
```
    Returns true if this node is labeled.
    
    Returns:
    
    true if this node is labeled; false otherwise
  - isLabeledTree
```
boolean isLabeledTree(java.util.Set<E> alphabet)
```
    Returns true if this tree is a labeled tree. A labeled tree is defined as a tree such that each node has a symbol assigned from a fixed finite alphabet.
    
    Parameters:
    
    alphabet - a set of elements to be compared with elements in this tree
    
    Returns:
    
    true if this tree is a labeled tree; false otherwise
  - yield
```
java.util.List<E> yield()
```
    Returns the yield of this tree as a list of elements of leaves.
    
    Returns:
    
    the yield of this tree
  - isBalanced
```
boolean isBalanced()
```
    Returns true if this tree is balanced. A balanced tree is a tree such that all leaf nodes of the tree are at the same depth.
    
    Returns:
    
    true if this tree is balanced; false otherwise

Interface Tree<E>

Method Summary

Methods inherited from interface java.util.Collection

Methods inherited from interface java.lang.Iterable

Method Detail

equals

hashCode

find

findChild

depth

depth

getParent

hasParent

hasParent

hasParent

degree

degree

numChildren

hasChild

hasChild

addChild

getSiblingElements

numSiblings

getRoot

isRoot

getAncestorElements

remove

removeChild

removeChildren

removeChildren

hasAncestor

hasAncestor

hasDescendant

hasDescendant

getElements

getNodes

isLeaf

numLeaves

getElement

setElement

hasElement

hasElement

isLabeled

isLabeledTree

yield

isBalanced