edu.rice.cs.plt.collect
Class AbstractRelation<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>

All Implemented Interfaces:

PredicateSet<Pair<T1,T2>>, Relation<T1,T2>, SizedIterable<Pair<T1,T2>>, Predicate<java.lang.Object>, Predicate2<T1,T2>, java.lang.Iterable<Pair<T1,T2>>, java.util.Collection<Pair<T1,T2>>, java.util.Set<Pair<T1,T2>>

Direct Known Subclasses:

AbstractFunctionalRelation, AbstractInjectiveRelation, CartesianRelation, ComposedRelation, FilteredRelation, IndexedRelation, UnindexedRelation, UnionRelation

public abstract class AbstractRelation<T1,T2>
extends AbstractPredicateSet<Pair<T1,T2>>
implements Relation<T1,T2>

An abstract parent class for implementations of Relation. Subclasses must provide the size methods isInfinite(), hasFixedSize(), and isStatic(), and the query methods contains(Object, Object), contains(Object), iterator(), firstSet(), matchFirst(T1), secondSet(), and matchSecond(T2). To support mutation, they must also override add(Object, Object) and remove(Object, Object). For best performance, they may also override AbstractPredicateSet.isEmpty(), AbstractPredicateSet.size(int) and AbstractCollection.clear().

Nested Class Summary

protected class

AbstractRelation.InverseRelation An inverse of the enclosing relation, defined in terms of Pair.inverse().

Constructor Summary

AbstractRelation()

Method Summary

boolean	add(Pair<T1,T2> p) Invokes add(Object, Object).
boolean	add(T1 first, T2 second) Add Pair.make(first, second) to the set.
abstract boolean	contains(java.lang.Object obj) Test whether the set contains an object.
abstract boolean	contains(T1 first, T2 second) Tests whether the given objects appear as a pair in this relation.
boolean	containsFirst(T1 first) Returns firstSet().contains(first).
boolean	containsSecond(T2 second) Returns secondSet().contains(second).
PredicateSet<T2>	excludeFirsts() Returns secondSet().
PredicateSet<T1>	excludeSeconds() Returns firstSet().
abstract PredicateSet<T1>	firstSet() The set of firsts.
abstract boolean	hasFixedSize() true if this iterable is known to have a fixed size.
Relation<T2,T1>	inverse() Returns an AbstractRelation.InverseRelation.
abstract boolean	isInfinite() true if the iterable is known to have infinite size.
abstract boolean	isStatic() true if this iterable is unchanging.
abstract java.util.Iterator<Pair<T1,T2>>	iterator()
abstract PredicateSet<T2>	matchFirst(T1 first) The set of seconds corresponding to a specific first.
abstract PredicateSet<T1>	matchSecond(T2 second) The set of firsts corresponding to a specific second.
boolean	remove(java.lang.Object o) Invokes remove(Object, Object) if contains(o) is true.
boolean	remove(T1 first, T2 second) Remove Pair.make(first, second) from the set.
abstract PredicateSet<T2>	secondSet() The set of seconds.

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

isEmpty, 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, isEmpty, removeAll, retainAll, size, toArray, toArray

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

isEmpty, size, size

Constructor Detail

AbstractRelation

public AbstractRelation()

Method Detail

isInfinite

public abstract 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>>

hasFixedSize

public abstract 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>>

isStatic

public abstract 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>>

contains

public abstract boolean contains(T1 first,
                                 T2 second)

Tests whether the given objects appear as a pair in this relation. Not guaranteed to have types T1 and T2 because the Collection.contains(java.lang.Object) method allows arbitrary objects.

Specified by:

contains in interface Relation<T1,T2>

Specified by:

contains in interface Predicate2<T1,T2>

contains

public abstract boolean contains(java.lang.Object obj)

Description copied from class: AbstractPredicateSet

Test whether the set contains an object. Overridden here to force subclasses to provide an implementation. The default implementation (AbstractCollection.contains(java.lang.Object)) is a linear search, which is almost always unreasonable for a set.

Specified by:

contains in interface Relation<T1,T2>

Specified by:

contains in interface Predicate<java.lang.Object>

Specified by:

contains in interface java.util.Collection<Pair<T1,T2>>

Specified by:

contains in interface java.util.Set<Pair<T1,T2>>

Specified by:

contains in class AbstractPredicateSet<Pair<T1,T2>>

iterator

public abstract java.util.Iterator<Pair<T1,T2>> iterator()

Specified by:

iterator in interface java.lang.Iterable<Pair<T1,T2>>

Specified by:

iterator in interface java.util.Collection<Pair<T1,T2>>

Specified by:

iterator in interface java.util.Set<Pair<T1,T2>>

Specified by:

iterator in class java.util.AbstractCollection<Pair<T1,T2>>

firstSet

public abstract PredicateSet<T1> firstSet()

Description copied from interface: Relation

The set of firsts. Need not allow mutation, but must reflect subsequent changes.

Specified by:

firstSet in interface Relation<T1,T2>

matchFirst

public abstract 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>

secondSet

public abstract PredicateSet<T2> secondSet()

Description copied from interface: Relation

The set of seconds. Need not allow mutation, but must reflect subsequent changes.

Specified by:

secondSet in interface Relation<T1,T2>

matchSecond

public abstract 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>

add

public boolean add(T1 first,
                   T2 second)

Description copied from interface: Relation

Add Pair.make(first, second) to the set.

Specified by:

add in interface Relation<T1,T2>

remove

public boolean remove(T1 first,
                      T2 second)

Description copied from interface: Relation

Remove Pair.make(first, second) from the set.

Specified by:

remove in interface Relation<T1,T2>

add

public boolean add(Pair<T1,T2> p)

Invokes add(Object, Object).

Specified by:

add in interface Relation<T1,T2>

Specified by:

add in interface java.util.Collection<Pair<T1,T2>>

Specified by:

add in interface java.util.Set<Pair<T1,T2>>

Overrides:

add in class java.util.AbstractCollection<Pair<T1,T2>>

remove

public boolean remove(java.lang.Object o)

Invokes remove(Object, Object) if contains(o) is true.

Specified by:

remove in interface Relation<T1,T2>

Specified by:

remove in interface java.util.Collection<Pair<T1,T2>>

Specified by:

remove in interface java.util.Set<Pair<T1,T2>>

Overrides:

remove in class java.util.AbstractCollection<Pair<T1,T2>>

inverse

public Relation<T2,T1> inverse()

Returns an AbstractRelation.InverseRelation.

Specified by:

inverse in interface Relation<T1,T2>

containsFirst

public boolean containsFirst(T1 first)

Returns firstSet().contains(first).

Specified by:

containsFirst in interface Relation<T1,T2>

excludeFirsts

public PredicateSet<T2> excludeFirsts()

Returns secondSet().

Specified by:

excludeFirsts in interface Relation<T1,T2>

containsSecond

public boolean containsSecond(T2 second)

Returns secondSet().contains(second).

Specified by:

containsSecond in interface Relation<T1,T2>

excludeSeconds

public PredicateSet<T1> excludeSeconds()

Returns firstSet().

Specified by:

excludeSeconds in interface Relation<T1,T2>