org.abora.white.collection.tables
Class HashTable

java.lang.Object
  |
  +--org.abora.white.xpp.basic.Heaper
        |
        +--org.abora.white.collection.tables.ScruTable
              |
              +--org.abora.white.collection.tables.MuTable
                    |
                    +--org.abora.white.collection.tables.HashTable

Direct Known Subclasses:

ActualHashTable

public abstract class HashTable

extends MuTable

Constructor Summary

protected	HashTable()
protected	HashTable(Rcvr rcvr)

Method Summary

abstract Heaper	atStore(Position key, Heaper value) Associate value with key, whether or not there is a previous association.
abstract CoordinateSpace	coordinateSpace() The kind of elements used to index into the table are Positions of this coordinate space.
abstract ScruTable	copy() A new one whose initial state is my current state, but that doesn't track changes.
abstract IntegerValue	count() Return the number of domain elements, which is to say, the number of associations.
abstract XnRegion	domain() Return an XuRegion representing a snapshot of the current domain.
abstract ScruTable	emptySize(IntegerValue size) Return an empty table just like the current one.
abstract Heaper	fetch(Position key) Return the range element at the domain position key.
abstract boolean	includesKey(Position aKey) includesKey is used to test for the presence of a key->value pair in the table.
abstract boolean	isEmpty() Is there anything in the table? 'table->isEmpty()' iff 'table->domain()->isEmpty()'.
static MuTable	make(CoordinateSpace cs) A new empty MuTable whose domain space is 'cs'.
static HashTable	make(CoordinateSpace cs, IntegerValue size)
abstract XnRegion	runAt(Position key) Return the length of the run starting at position key.
abstract TableStepper	stepper(OrderSpec order) Return a TableStepper which will enumerate my key->value mappings.
abstract ScruTable	subTable(XnRegion reg) Return a table which contains only the intersection of this table's domain and the domain specified by 'region'.
abstract Heaper	theOne() Iff I contain exactly one range element, return it.
abstract boolean	wipe(Position anIdx) Remove a key->value association from the table.

Methods inherited from class org.abora.white.collection.tables.MuTable

actualHashForEqual, asImmuTable, asMuTable, atIntIntroduce, atIntReplace, atIntroduce, atIntStore, atReplace, includesIntKey, intFetch, intRemove, introduceAll, introduceAll, introduceAll, intWipe, isEqual, make, problems, remove, removeAll, replaceAll, replaceAll, replaceAll, runAtInt, sendSelfTo, storeAll, storeAll, storeAll, wipeAll

Methods inherited from class org.abora.white.collection.tables.ScruTable

backfollowFrom, contentsEqual, contentsHash, get, intGet, printOn, printOnWithSimpleSyntax, printOnWithSyntax, range, stepper, transformedBy

Methods inherited from class org.abora.white.xpp.basic.Heaper

destroy, destruct, equals, hashForEqual, printContentsOn, toString

Methods inherited from class java.lang.Object

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

Constructor Detail

HashTable

protected HashTable()

HashTable

protected HashTable(Rcvr rcvr)

Method Detail

atStore

public abstract Heaper atStore(Position key,
                               Heaper value)

Associate value with key, whether or not there is a previous association.

Specified by:

atStore in class MuTable

coordinateSpace

public abstract CoordinateSpace coordinateSpace()

Description copied from class: ScruTable

The kind of elements used to index into the table are Positions of this coordinate space. Therefore, the domain of this table is an XuRegion in this coordinate space.

Specified by:

coordinateSpace in class MuTable

count

public abstract IntegerValue count()

Description copied from class: ScruTable

Return the number of domain elements, which is to say, the number of associations. 'table->count()' should be equivalent to 'table->domain()->count()'. Used to say: 'Return the number of range elements'. This seems clearly wrong.

Specified by:

count in class MuTable

domain

public abstract XnRegion domain()

Description copied from class: ScruTable

Return an XuRegion representing a snapshot of the current domain. 'table->domain()->hasMember(p)' iff 'table->fetch(p) !!= NULL'.

Specified by:

domain in class MuTable

fetch

public abstract Heaper fetch(Position key)

Description copied from class: ScruTable

Return the range element at the domain position key. The routine will return NULL if the position is not in the table.

Specified by:

fetch in class MuTable

subTable

public abstract ScruTable subTable(XnRegion reg)

Description copied from class: ScruTable

Return a table which contains only the intersection of this table's domain and the domain specified by 'region'. table->subTable(r)->domain()->isEqual( table->domain()->intersect(r) ). It is unspecified whether the resulting table starts as a snapshot of a subset of me, after which we go our own ways; or whether the resulting table is a view onto a subset of me, such that changes to me are also visible to him. Of course, subclasses may specify more. If you want to ensure snapshot behavior, do 'table->subTable(r)->asImmuTable()'. NOTE: In the future we may specify snapshot behavior or we may specify view behavior. As a client this shouldn't effect you. However, if you implement a new kind of ScruTable, please let us know. Also, if you have an opinion as to which way you'd like the specification tightened up, please tell us.

Specified by:

subTable in class MuTable

wipe

public abstract boolean wipe(Position anIdx)

Remove a key->value association from the table. Do not blast (or do anything else) if the key is not in my current domain.

Specified by:

wipe in class MuTable

includesKey

public abstract boolean includesKey(Position aKey)

Description copied from class: ScruTable

includesKey is used to test for the presence of a key->value pair in the table. This routine returns true if there is a value present at the specified key, and false otherwise. 'table->includesKey(p)' iff 'table->domain()->hasMember(p)'.

Specified by:

includesKey in class MuTable

isEmpty

public abstract boolean isEmpty()

Description copied from class: ScruTable

Is there anything in the table? 'table->isEmpty()' iff 'table->domain()->isEmpty()'.

Specified by:

isEmpty in class MuTable

stepper

public abstract TableStepper stepper(OrderSpec order)

Description copied from class: ScruTable

Return a TableStepper which will enumerate my key->value mappings. The Stepper component of the TableStepper protocol will just enumerate my values (as that is what I'm a container *of*--the keys are simply how I organize my contents). TableStepper provides additional protocol to ascetain the current key. See TableStepper and XuRegion::stepper. The TableStepper I produce given an order must enumerate keys according to the same rules which specify how XuRegion::stepper must enumerate positions. I am not asserting that the actual orders are the same, only that the correctness criteria on the allowable orders are the same. Keeping in mind that we are talking about equivalence of specification and not equivalence of particular behavior, the following two statements are equivalent: { SPTR(TableStepper) stomp = table->stepper(o); SPTR(Position) key; FOR_EACH(Heaper,val,stomp, { key = stomp->key(); doSomethingWith(key, val); }); } and { SPTR(Heaper) val; SPTR(ImmuTable) snapShot = table->asImmuTable(); FOR_EACH(Position,key,(snapShot->domain()->stepper(o)), { val = snapShot->get (key); doSomethingWith(key, val); }); }

Specified by:

stepper in class MuTable

theOne

public abstract Heaper theOne()

Description copied from class: ScruTable

Iff I contain exactly one range element, return it. Otherwise BLAST. The idea for this message is taken from the THE function of ONTIC (reference McAllester)

Overrides:

theOne in class ScruTable

runAt

public abstract XnRegion runAt(Position key)

Description copied from class: ScruTable

Return the length of the run starting at position key. A run is defined as a contiguous (charming) sequence of domain positions mapping to equal (isEqual) objects. Charming is defined as: Given a charming region R, for all a,c which are elements of R and a >= b >= c, b is an element of R. Where '>=' is according to the 'isGE' message. NOTE: We may retire the above definition of charming. The possible changes will only effect spaces which aren't fully ordered. OrderedRegions, TreeRegions, and IntegerRegions will be unaffected, as any future definition of 'runAt' will be equivalent for them.

Specified by:

runAt in class MuTable

copy

public abstract ScruTable copy()

Description copied from class: ScruTable

A new one whose initial state is my current state, but that doesn't track changes. Note that there is no implication that these can be 'destroy'ed separately, because (for example) an ImmuTable just returns itself

Specified by:

copy in class MuTable

emptySize

public abstract ScruTable emptySize(IntegerValue size)

Description copied from class: ScruTable

Return an empty table just like the current one. The 'size' argument is a hint about how big the count of the table will probably become (so that the new table can be prepared to grow to that size efficiently).

Specified by:

emptySize in class MuTable

make

public static MuTable make(CoordinateSpace cs)

Description copied from class: MuTable

A new empty MuTable whose domain space is 'cs'.

make

public static HashTable make(CoordinateSpace cs,
                             IntegerValue size)