edu.rice.cs.plt.collect
Class IntersectionRelation<T1,T2>

java.lang.Object
  java.util.AbstractCollection<E>
      java.util.AbstractSet<T>
          edu.rice.cs.plt.collect.AbstractPredicateSet<Pair<T1,T2>>
              edu.rice.cs.plt.collect.AbstractRelation<T1,T2>
                  edu.rice.cs.plt.collect.FilteredRelation<T1,T2>
                      edu.rice.cs.plt.collect.IntersectionRelation<T1,T2>

All Implemented Interfaces:

PredicateSet<Pair<T1,T2>>, Relation<T1,T2>, SizedIterable<Pair<T1,T2>>, Predicate<Object>, Predicate2<T1,T2>, Composite, Serializable, Iterable<Pair<T1,T2>>, Collection<Pair<T1,T2>>, Set<Pair<T1,T2>>

public class IntersectionRelation<T1,T2>
extends FilteredRelation<T1,T2>

The intersection of two relations, lazily constructed and updated dynamically. This improves on a general FilteredRelation by taking advantage of the fact that the predicate used for filtering is also a relation.

See Also:

Serialized Form

Nested Class Summary

Nested classes/interfaces inherited from class edu.rice.cs.plt.collect.AbstractRelation

AbstractRelation.InverseRelation

Field Summary

Fields inherited from class edu.rice.cs.plt.collect.FilteredRelation

_pred, _rel

Constructor Summary

IntersectionRelation(Relation<? super T1,? super T2> rel1, Relation<T1,T2> rel2)
For best performance of FilteredRelation.iterator(), AbstractPredicateSet.size(), and isEmpty(), set2 should be the smaller of the two sets (this is not handled automatically because calculating sizes may be expensive).

Method Summary

boolean	hasFixedSize() true if this iterable is known to have a fixed size.
boolean	isEmpty() Returns size(1) == 0.
boolean	isInfinite() true if the iterable is known to have infinite size.
boolean	isStatic() true if this iterable is unchanging.
PredicateSet<T2>	matchFirst(T1 first) The set of seconds corresponding to a specific first.
PredicateSet<T1>	matchSecond(T2 second) The set of firsts corresponding to a specific second.

Methods inherited from class edu.rice.cs.plt.collect.FilteredRelation

compositeHeight, compositeSize, contains, contains, firstSet, iterator, secondSet

Methods inherited from class edu.rice.cs.plt.collect.AbstractRelation

add, add, containsFirst, containsSecond, excludeFirsts, excludeSeconds, inverse, remove, remove

Methods inherited from class edu.rice.cs.plt.collect.AbstractPredicateSet

size, size

Methods inherited from class java.util.AbstractSet

equals, hashCode, removeAll

Methods inherited from class java.util.AbstractCollection

addAll, clear, containsAll, retainAll, toArray, toArray, toString

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.util.Set

addAll, clear, containsAll, equals, hashCode, removeAll, retainAll, size, toArray, toArray

Methods inherited from interface edu.rice.cs.plt.iter.SizedIterable

size, size

Constructor Detail

IntersectionRelation

public IntersectionRelation(Relation<? super T1,? super T2> rel1,
                            Relation<T1,T2> rel2)

For best performance of FilteredRelation.iterator(), AbstractPredicateSet.size(), and isEmpty(), set2 should be the smaller of the two sets (this is not handled automatically because calculating sizes may be expensive).

Method Detail

matchFirst

public PredicateSet<T2> matchFirst(T1 first)

Description copied from interface: Relation

The set of seconds corresponding to a specific first. Need not allow mutation, but must reflect subsequent changes.

Specified by:

matchFirst in interface Relation<T1,T2>

Overrides:

matchFirst in class FilteredRelation<T1,T2>

matchSecond

public PredicateSet<T1> matchSecond(T2 second)

Description copied from interface: Relation

The set of firsts corresponding to a specific second. Need not allow mutation, but must reflect subsequent changes.

Specified by:

matchSecond in interface Relation<T1,T2>

Overrides:

matchSecond in class FilteredRelation<T1,T2>

isInfinite

public boolean isInfinite()

Description copied from interface: SizedIterable

true if the iterable is known to have infinite size. If true, an iterator over the iterable in its current state will never return false from hasNext().

Specified by:

isInfinite in interface SizedIterable<Pair<T1,T2>>

Overrides:

isInfinite in class FilteredRelation<T1,T2>

hasFixedSize

public boolean hasFixedSize()

Description copied from interface: SizedIterable

true if this iterable is known to have a fixed size. This is the case if the iterable is immutable, or if changes can only replace values, not remove or add them. An infinite iterable may be fixed if it is guaranteed to never become finite.

Specified by:

hasFixedSize in interface SizedIterable<Pair<T1,T2>>

Overrides:

hasFixedSize in class FilteredRelation<T1,T2>

isStatic

public boolean isStatic()

Description copied from interface: SizedIterable

true if this iterable is unchanging. This implies that hasFixedSize() is true, and that iterator() will always return the same (either == or equal() and immutable) elements in the same order. ("Immutable" here means that equals() invocations are consistent over time -- if two objects are equal, they will never become inequal, and vice versa.)

Specified by:

isStatic in interface SizedIterable<Pair<T1,T2>>

Overrides:

isStatic in class FilteredRelation<T1,T2>

isEmpty

public boolean isEmpty()

Description copied from class: AbstractPredicateSet

Returns size(1) == 0.

Specified by:

isEmpty in interface SizedIterable<Pair<T1,T2>>

Specified by:

isEmpty in interface Collection<Pair<T1,T2>>

Specified by:

isEmpty in interface Set<Pair<T1,T2>>

Overrides:

isEmpty in class FilteredRelation<T1,T2>