edu.vt.marian.search
Class WtdObjDoubleLink

java.lang.Object
  |
  +--edu.vt.marian.common.FullID
        |
        +--edu.vt.marian.common.WtdObj
              |
              +--edu.vt.marian.search.WtdObjSingleLink
                    |
                    +--edu.vt.marian.search.WtdObjDoubleLink

public class WtdObjDoubleLink

extends WtdObjSingleLink

This class augments singly-linked weighted objects with a "pointer" to a "previous" FullID key. This is to enable the creation of weighted object tables which are "threaded" like a doubly-linked list. The purpose of such a table is to allow O(1) ("direct") access to any point in the logical list, but thereafter to "follow" the entries in the list from that point forwards or backwards.

See Also:

WtdObj, FullID, Debug

Field Summary

protected edu.vt.marian.common.FullID

previous "Pointer" to the previous "list" entry

Fields inherited from class edu.vt.marian.search.WtdObjSingleLink

next

Fields inherited from class edu.vt.marian.common.WtdObj

INVALID, weight

Fields inherited from class edu.vt.marian.common.FullID

BAD_PARAMS, classID, debug, instanceID, MAX_CLASS_ID, MAX_INSTANCE_ID, NULL_STREAM, OK

Constructor Summary

WtdObjDoubleLink(edu.vt.marian.common.Debug debug)
Create a doubly-linked weighted object given only a debug object.

WtdObjDoubleLink(edu.vt.marian.common.WtdObj w, edu.vt.marian.common.Debug debug)
Create a doubly-linked weighted object given a weighted object and a debug object.

WtdObjDoubleLink(edu.vt.marian.common.WtdObj w, edu.vt.marian.common.FullID next, edu.vt.marian.common.Debug debug)
Create a doubly-linked weighted object given a weighted object, a FullID pointing to the "next" list item, and a debug object.

WtdObjDoubleLink(edu.vt.marian.common.WtdObj w, edu.vt.marian.common.FullID next, edu.vt.marian.common.FullID prev, edu.vt.marian.common.Debug debug)
Create a doubly-linked weighted object given a weighted object, a FullID pointing to the "next" list item, and a debug object.

Method Summary

edu.vt.marian.common.FullID	getPrevious() Return the FullID key of the previous item pointed to in this ordering.
java.lang.String	toString() Convert this WtdObjDoubleLink to a string representation.

Methods inherited from class edu.vt.marian.search.WtdObjSingleLink

getNext, setNext

Methods inherited from class edu.vt.marian.common.WtdObj

accum, accum, compare, compare, getID, getWeight, isValid, readPacked, scale, scale, toStream, writePacked

Methods inherited from class edu.vt.marian.common.FullID

equals, getClassID, getInstanceID, hashCode, setClassID, setInstanceID

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Field Detail

previous

protected edu.vt.marian.common.FullID previous

"Pointer" to the previous "list" entry

Constructor Detail

WtdObjDoubleLink

public WtdObjDoubleLink(edu.vt.marian.common.Debug debug)

Create a doubly-linked weighted object given only a debug object. The resultant object will have its weighted object set to a newly-created WtdObj and its previous and next "pointers" set to newly-created---and invalid---FullIDs.

Parameters:

debug - debug object

WtdObjDoubleLink

public WtdObjDoubleLink(edu.vt.marian.common.WtdObj w,
                        edu.vt.marian.common.Debug debug)

Create a doubly-linked weighted object given a weighted object and a debug object. The resultant object will have its next and previous "pointers" set to newly-created---and invalid---FullIDs.

Parameters:

w - weighted object

debug - debug object

WtdObjDoubleLink

public WtdObjDoubleLink(edu.vt.marian.common.WtdObj w,
                        edu.vt.marian.common.FullID next,
                        edu.vt.marian.common.Debug debug)

Create a doubly-linked weighted object given a weighted object, a FullID pointing to the "next" list item, and a debug object. The resultant object will have its next "pointer" set to the one given, and its "previous" pointer to a newly-created---and invalid---FullID.

Parameters:

w - weighted object

next - key of next element in this list

debug - debug object

WtdObjDoubleLink

public WtdObjDoubleLink(edu.vt.marian.common.WtdObj w,
                        edu.vt.marian.common.FullID next,
                        edu.vt.marian.common.FullID prev,
                        edu.vt.marian.common.Debug debug)

Create a doubly-linked weighted object given a weighted object, a FullID pointing to the "next" list item, and a debug object. The resultant object will have its next "pointer" set to the one given, and its "previous" pointer to a newly-created---and invalid---FullID.

Parameters:

w - weighted object

next - key of next element in this list

prev - key of previous element in this list

debug - debug object

Method Detail

getPrevious

public edu.vt.marian.common.FullID getPrevious()

Return the FullID key of the previous item pointed to in this ordering.

Returns:

key of the next weighted object in this ordering

toString

public java.lang.String toString()

Convert this WtdObjDoubleLink to a string representation. The printable form is "WtdObjSingleLink(FullID)", where WtdObjSingleLink is the string representation of the singly-linked weighted object portion of this object, and the FullIDs are the string representations of the FullID "next" and "previous" pointers of this object respectively.

Returns:

string containing printable representation of object data

Overrides:

toString in class WtdObjSingleLink

See Also:

WtdObjSingleLink.toString(), FullID.toString()