Package components.tree

Interface TreeKernel<T>

Type Parameters:

T - type of TreeKernel node labels

All Superinterfaces:

Iterable<T>, Standard<Tree<T>>

All Known Subinterfaces:

Tree<T>

All Known Implementing Classes:

Tree1, TreeSecondary

public interface TreeKernel<T>
extends Standard<Tree<T>>, Iterable<T>

Tree kernel component with primary methods. (Note: by package-wide convention, all references are non-null.)

Mathematical Definitions:

PRE_ORDER(
  t: tree of T
 ): string of T satisfies
 if t = empty_tree
  then PRE_ORDER(tree) = <>
  else there exists root: T, children: string of tree of T
        (t = compose(root, children) and
         PRE_ORDER(t) = <root> * STRING_PRE_ORDER(children))

STRING_PRE_ORDER(
  s: string of tree of T
 ): string of T satisfies
 if s = empty_string
  then STRING_PRE_ORDER(s) = <>
  else there exists t: tree of T, rest: string of tree of T
        (s = <t> * rest and
         STRING_PRE_ORDER(s) = PRE_ORDER(t) * STRING_PRE_ORDER(rest))

Mathematical Model (abstract value and abstract invariant of this):

type TreeKernel is modeled by tree of T

Constructor(s) (initial abstract value(s) of this):

():
 ensures
  this = empty_tree

Iterator String (abstract value of ~this):

~this.seen * ~this.unseen = PRE_ORDER(this)

Method Summary

Modifier and Type	Method	Description
void	assemble(T root, Sequence<Tree<T>> children)	Assembles in this a tree with root label root and subtrees children; the declaration notwithstanding, the dynamic type of each entry of children must be the same as the dynamic type of this and the dynamic type of children must be the same as that returned by newSequenceOfTree.
T	disassemble(Sequence<Tree<T>> children)	Disassembles this into its root label, which is returned as the value of the function, and subtrees in children; the declaration notwithstanding, the dynamic type of children must be the same as that returned by newSequenceOfTree.
Sequence<Tree<T>>	newSequenceOfTree()	Creates and returns an empty Sequence<Tree<T>> of the dynamic type needed in assemble and disassemble.
int	size()	Reports the size of this.

Methods inherited from interface java.lang.Iterable

forEach, iterator, spliterator

Methods inherited from interface components.standard.Standard

clear, newInstance, transferFrom

Method Details

newSequenceOfTree

Sequence<Tree<T>> newSequenceOfTree()

Creates and returns an empty Sequence<Tree<T>> of the dynamic type needed in assemble and disassemble.

Returns:

a new empty Sequence<Tree<T>>

Ensures:

newSequenceOfTree = <>

assemble

void assemble(T root,
 Sequence<Tree<T>> children)

Assembles in this a tree with root label root and subtrees children; the declaration notwithstanding, the dynamic type of each entry of children must be the same as the dynamic type of this and the dynamic type of children must be the same as that returned by newSequenceOfTree.

Parameters:

root - the root label

children - the subtrees

Aliases:

reference root

Replaces:

this

Clears:

children

Ensures:

this = compose(root, #children)

disassemble

T disassemble(Sequence<Tree<T>> children)

Disassembles this into its root label, which is returned as the value of the function, and subtrees in children; the declaration notwithstanding, the dynamic type of children must be the same as that returned by newSequenceOfTree.

Parameters:

children - the subtrees

Returns:

the root label

Replaces:

children

Clears:

this

Requires:

this /= empty_tree

Ensures:

#this = compose(disassemble, children)

size

int size()

Reports the size of this.

Returns:

the size

Ensures:

size = |this|