textmaven.tst
Class TSTIterator

java.lang.Object
  textmaven.tst.TSTIterator

All Implemented Interfaces:

java.util.Iterator

Direct Known Subclasses:

TSTCountIterator

public class TSTIterator

extends java.lang.Object

implements java.util.Iterator

Read only iterator for TST.

Author:

Peter Kolloch

Field Summary

protected static int[]	REL_TO_STATE Conversion array from node relative constants to states.
protected static int[]	STATE_TO_REL Converstion from states to node relative constants.
static int	STATE0_LO Inspect child with lower key next
static int	STATE1_NODE Inspect current node next
static int	STATE2_EQ Inspect child with equal, but longer key next
static int	STATE3_HI Inspect child with higher key next
static int	STATE4_DONE Move back to parent

Constructor Summary

TSTIterator(textmaven.tst.TSTNode root)
Constructs an iterator traversing the tree with the given root node.

Method Summary

protected void	calculateNext(int state) Starts looking for a plausible next node at the current node with the given state.
boolean	hasNext()
java.lang.Object	next()
TSTEntry	nextEntry() As next, but with the concrete rather than the abstract return type.
void	remove() NOT SUPPORTED!
protected boolean	visitNode(textmaven.tst.TSTNode node)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

STATE0_LO

public static final int STATE0_LO

Inspect child with lower key next

See Also:

Constant Field Values

STATE1_NODE

public static final int STATE1_NODE

Inspect current node next

See Also:

Constant Field Values

STATE2_EQ

public static final int STATE2_EQ

Inspect child with equal, but longer key next

See Also:

Constant Field Values

STATE3_HI

public static final int STATE3_HI

Inspect child with higher key next

See Also:

Constant Field Values

STATE4_DONE

public static final int STATE4_DONE

Move back to parent

See Also:

Constant Field Values

REL_TO_STATE

protected static final int[] REL_TO_STATE

Conversion array from node relative constants to states.

STATE_TO_REL

protected static final int[] STATE_TO_REL

Converstion from states to node relative constants.

Constructor Detail

TSTIterator

public TSTIterator(textmaven.tst.TSTNode root)

Constructs an iterator traversing the tree with the given root node. The returned keys are relative to the given root.

Parameters:

root - the root of the traversed sub tree (not tested for anything but the root node)

Method Detail

remove

public void remove()

NOT SUPPORTED!

Specified by:

remove in interface java.util.Iterator

visitNode

protected boolean visitNode(textmaven.tst.TSTNode node)

calculateNext

protected void calculateNext(int state)

Starts looking for a plausible next node at the current node with the given state. The states are explained in the doc of the state constants. The result is stored in the nextNode instance variable. If nextNode != null nothing is done.

See Also:

STATE0_LO, STATE1_NODE, STATE2_EQ, STATE3_HI, STATE4_DONE

hasNext

public boolean hasNext()

Specified by:

hasNext in interface java.util.Iterator

See Also:

Iterator.hasNext()

next

public java.lang.Object next()

Specified by:

next in interface java.util.Iterator

See Also:

Iterator.next()

nextEntry

public TSTEntry nextEntry()

As next, but with the concrete rather than the abstract return type.