org.abora.white.collection.tables
Class ImmuTable

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

Direct Known Subclasses:

ImmuTableOnMu, OffsetImmuTable

public abstract class ImmuTable

extends ScruTable

ImmuTable are to ScruTables much like ImmuSets are to ScruSets. See ImmuSet. The ImmuTable subclass of tables represents all tables which CANNOT be side-effected during operations on them. They are intended to represent mathematical abstractions (such as vectors) and are intended to be used in a functional-programming style. Operations are provided for building new ImmuTables out of old ones.

Constructor Summary

protected	ImmuTable()
protected	ImmuTable(Rcvr rcvr)

Method Summary

int	actualHashForEqual() See ScruTable::isEqual
ImmuTable	asImmuTable() Return a side-effect-free snapshot of my current contents.
abstract MuTable	asMuTable() Return a side-effectable version of the same table.
abstract ImmuTable	combineWith(ImmuTable other) Similar to unionWith.
abstract CoordinateSpace	coordinateSpace() The kind of elements used to index into the table are Positions of this coordinate space.
ScruTable	copy() don't need to actually make a copy, as this is immutable
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) The idea of a 'size' argument would seem kind of ridiculous here as the resulting empty table can't be changed.
abstract Heaper	fetch(Position key) Return the range element at the domain position key.
boolean	includesIntKey(IntegerValue aKey) Unboxed version.
abstract boolean	includesKey(Position aKey) includesKey is used to test for the presence of a key->value pair in the table.
Heaper	intFetch(IntegerValue key) Unboxed version.
abstract boolean	isEmpty() Is there anything in the table? 'table->isEmpty()' iff 'table->domain()->isEmpty()'.
boolean	isEqual(Heaper other) All MuTable subclasses have equality based on identity (now and forever equal.
static Heaper	make(CoordinateSpace cs) An empty ImmuTable whose domain space is 'cs'.
static Heaper	make(java.lang.Object something) (something isKindOf: MuTable) ifTrue: [^self make.MuTable: something].
static ImmuTable	offsetImmuTable(ImmuTable aTable, Dsp aDsp)
abstract XnRegion	runAt(Position key) Return the length of the run starting at position key.
abstract XnRegion	runAtInt(IntegerValue key) Unboxed version.
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'.
ScruTable	transformedBy(Dsp dsp) Return a ScruTable with the domain of the receiver transformed by the Dsp.
abstract ImmuTable	without(Position index) Return a new table just like the current one except with the association whose key is 'index'.

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

backfollowFrom, contentsEqual, contentsHash, get, intGet, printOn, printOnWithSimpleSyntax, printOnWithSyntax, problems, range, stepper, theOne

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

destroy, destruct, equals, hashForEqual, printContentsOn, sendSelfTo, toString

Methods inherited from class java.lang.Object

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

Constructor Detail

ImmuTable

protected ImmuTable()

ImmuTable

protected ImmuTable(Rcvr rcvr)

Method Detail

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 ScruTable

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 ScruTable

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 ScruTable

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 ScruTable

intFetch

public Heaper intFetch(IntegerValue key)

Description copied from class: ScruTable

Unboxed version. See class comment for XuInteger

Overrides:

intFetch 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 ScruTable

runAtInt

public abstract XnRegion runAtInt(IntegerValue key)

Description copied from class: ScruTable

Unboxed version. See class comment for XuInteger

Overrides:

runAtInt in class ScruTable

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 ScruTable

transformedBy

public ScruTable transformedBy(Dsp dsp)

Return a ScruTable with the domain of the receiver transformed by the Dsp. 'table->transformedBy(d)->fetch(p)' is equivalent to 'table->fetch(d->of(p))'. See ScruTable::subTable for caveats regarding whether we return a snapshot or a view. All the same caveats apply. In this case of transforming an ImmuTable, it makes sense to return an ImmuTable.

Overrides:

transformedBy in class ScruTable

copy

public ScruTable copy()

don't need to actually make a copy, as this is immutable

Specified by:

copy in class ScruTable

emptySize

public abstract ScruTable emptySize(IntegerValue size)

The idea of a 'size' argument would seem kind of ridiculous here as the resulting empty table can't be changed.

Specified by:

emptySize in class ScruTable

combineWith

public abstract ImmuTable combineWith(ImmuTable other)

Similar to unionWith. In particular, if 'a = b->combineWith(c);', then: 'a->domain()->isEqual(b->domain()->unionWith(c->domain())' and 'a->range()->isSubsetOf(b->range()->unionWith(c->range())'. (Note that the domain case uses XuRegion::unionWith, while the range case uses ImmuSet::unionWith.) Despite this correspondence, unionWith is symmetrical while combineWith is not. Given that the two input tables have different associations for a given key, one gets to dominate. I need to specify which one here, but the code seems inconsistent on this question. Until this is resolved, console youself with the thought that if the tables don't conflict we have a simple unionWith of the two sets of associations (and the 'isSubsetOf' above can be replaced with 'isEqual').

without

public abstract ImmuTable without(Position index)

Return a new table just like the current one except with the association whose key is 'index'.

actualHashForEqual

public int actualHashForEqual()

Description copied from class: ScruTable

See ScruTable::isEqual

Overrides:

actualHashForEqual in class ScruTable

includesIntKey

public boolean includesIntKey(IntegerValue aKey)

Description copied from class: ScruTable

Unboxed version. See class comment for XuInteger

Overrides:

includesIntKey in class ScruTable

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)'.

Overrides:

includesKey in class ScruTable

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 ScruTable

isEqual

public boolean isEqual(Heaper other)

Description copied from class: ScruTable

All MuTable subclasses have equality based on identity (now and forever equal. Many ScruTable subclasses will represent an aspect of another table. Therefore they have hashForEqual and isEqual: based on both their contained table, and the aspect that they represent. Thus, two similar views onto the same MuTable are now (and forever) equal. The hashForEqual: must use exactly the same aspects for the hash as get used for isEqual:. ImmuTables all use contentBased comparison operations.

Specified by:

isEqual in class ScruTable

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 ScruTable

asImmuTable

public ImmuTable asImmuTable()

Description copied from class: ScruTable

Return a side-effect-free snapshot of my current contents. See ScruSet::asImmuSet.

Specified by:

asImmuTable in class ScruTable

asMuTable

public abstract MuTable asMuTable()

Description copied from class: ScruTable

Return a side-effectable version of the same table. See ScruSet::asMuSet.

Specified by:

asMuTable in class ScruTable

make

public static Heaper make(CoordinateSpace cs)

An empty ImmuTable whose domain space is 'cs'.

offsetImmuTable

public static ImmuTable offsetImmuTable(ImmuTable aTable,
                                        Dsp aDsp)

make

public static Heaper make(java.lang.Object something)

(something isKindOf: MuTable) ifTrue: [^self make.MuTable: something].