io.permazen.core.util

Class ObjIdBiMultiMap

java.lang.Object

io.permazen.core.util.ObjIdBiMultiMap

All Implemented Interfaces:

Serializable, Cloneable

@ThreadSafe
public class ObjIdBiMultiMap
extends Object
implements Cloneable, Serializable

A bi-directional, many-to-many mapping between ObjIds.

Instances can be thought of as containing a set of source, target ordered pairs. The many-to-many mapping can be efficiently queried and modified from either direction.

Instances of this class are thread-safe.

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
ObjIdBiMultiMap() Default constructor.
ObjIdBiMultiMap(int sourceCapacity, int targetCapacity) Constructs an instance with the given initial capacities.

Method Summary

Modifier and Type	Method and Description
boolean	add(ObjId source, ObjId target) Add an association.
boolean	addAll(ObjId source, Iterable<? extends ObjId> targets) Add multiple associations with a given source.
void	clear() Clear this instance.
ObjIdBiMultiMap	clone() Clone this instance.
boolean	containsSource(ObjId source) Determine if this instance has any targets associated with the specified source.
boolean	containsTarget(ObjId target) Determine if this instance has any sources associated with the specified target.
boolean	equals(Object obj) Compare for equality.
int	getNumSources() Get the the number of sources that have one or more associated targets.
int	getNumTargets() Get the the number of targets that have one or more associated sources.
ObjIdSet	getSources() Get all sources associated with this instance that have one or more associated targets.
ObjIdSet	getSources(ObjId target) Get the sources associated with the given target, if any.
ObjIdSet	getTargets() Get all targets associated with this instance that have one or more associated sources.
ObjIdSet	getTargets(ObjId source) Get the targets associated with the given source, if any.
int	hashCode() Calculate a hash code value for this instance.
ObjIdBiMultiMap	inverse() Get an inverse view backed by this instance.
boolean	remove(ObjId source, ObjId target) Remove an association.
boolean	removeAll(ObjId source, Iterable<? extends ObjId> targets) Remove multiple associations with a given source.
boolean	removeSource(ObjId source) Remove all associations involving the specified source.
boolean	removeTarget(ObjId target) Remove all associations involving the specified target.
String	toString() Create a String representation.

Methods inherited from class java.lang.Object

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

Constructor Detail

ObjIdBiMultiMap

public ObjIdBiMultiMap()

Default constructor.

ObjIdBiMultiMap

public ObjIdBiMultiMap(int sourceCapacity,
                       int targetCapacity)

Constructs an instance with the given initial capacities.

Parameters:

sourceCapacity - initial capacity for the number of sources

targetCapacity - initial capacity for the number of targets

Throws:

IllegalArgumentException - if either value is negative

Method Detail

getNumSources

public int getNumSources()

Get the the number of sources that have one or more associated targets.

Returns:

the number of sources contained in this instance

getNumTargets

public int getNumTargets()

Get the the number of targets that have one or more associated sources.

Returns:

the number of targets contained in this instance

getSources

public ObjIdSet getSources()

Get all sources associated with this instance that have one or more associated targets.

The returned ObjIdSet is mutable, but changes to it do not affect this instance.

Returns:

all source ID's associated with this instance, possibly empty

getTargets

public ObjIdSet getTargets()

Get all targets associated with this instance that have one or more associated sources.

The returned ObjIdSet is mutable, but changes to it do not affect this instance.

Returns:

all targets ID's associated with this instance, possibly empty

getSources

public ObjIdSet getSources(ObjId target)

Get the sources associated with the given target, if any.

The returned ObjIdSet is mutable, but changes to it do not affect this instance.

Parameters:

target - target ID

Returns:

one or more source ID's associated with target, or null if there are none

Throws:

IllegalArgumentException - if target is null

getTargets

public ObjIdSet getTargets(ObjId source)

Get the targets associated with the given source, if any.

The returned ObjIdSet is mutable, but changes to it do not affect this instance.

Parameters:

source - source ID

Returns:

one or more target ID's associated with source, or null if there are none

Throws:

IllegalArgumentException - if source is null

containsSource

public boolean containsSource(ObjId source)

Determine if this instance has any targets associated with the specified source.

Parameters:

source - source ID

Returns:

true if any target ID's are associated with source, otherwise false

Throws:

IllegalArgumentException - if source is null

containsTarget

public boolean containsTarget(ObjId target)

Determine if this instance has any sources associated with the specified target.

Parameters:

target - target ID

Returns:

true if any source ID's are associated with target, otherwise false

Throws:

IllegalArgumentException - if target is null

add

public boolean add(ObjId source,
                   ObjId target)

Add an association.

Parameters:

source - source ID

target - target ID

Returns:

true if association was added, false if the association already existed

Throws:

IllegalArgumentException - if source or target is null

addAll

public boolean addAll(ObjId source,
                      Iterable<? extends ObjId> targets)

Add multiple associations with a given source.

Parameters:

source - source ID

targets - target ID's

Returns:

true if any association was added, false if all associations already existed

Throws:

IllegalArgumentException - if source, targets, or any target in the iteration is null

remove

public boolean remove(ObjId source,
                      ObjId target)

Remove an association.

Parameters:

source - source ID

target - target ID

Returns:

true if association was removed, false if the association did not exist

Throws:

IllegalArgumentException - if source or target is null

removeAll

public boolean removeAll(ObjId source,
                         Iterable<? extends ObjId> targets)

Remove multiple associations with a given source.

Parameters:

source - source ID

targets - target ID's

Returns:

true if any association was removed, false if none of the specified associations existed

Throws:

IllegalArgumentException - if source, targets, or any target in the iteration is null

removeSource

public boolean removeSource(ObjId source)

Remove all associations involving the specified source.

Parameters:

source - source ID

Returns:

true if any source association(s) were removed, false if source had no target associations

Throws:

IllegalArgumentException - if source is null

removeTarget

public boolean removeTarget(ObjId target)

Remove all associations involving the specified target.

Parameters:

target - target ID

Returns:

true if any target association(s) were removed, false if target had no source associations

Throws:

IllegalArgumentException - if target is null

clear

public void clear()

Clear this instance.

inverse

public ObjIdBiMultiMap inverse()

Get an inverse view backed by this instance.

The returned ObjIdBiMultiMap is a view in which sources become targets and vice-versa; any changes are reflected back in this instance.

This method is efficient, requiring only constant time.

Returns:

inverse view of this instance

hashCode

public int hashCode()

Calculate a hash code value for this instance.

Overrides:

hashCode in class Object

equals

public boolean equals(Object obj)

Compare for equality.

Overrides:

equals in class Object

toString

public String toString()

Create a String representation.

Overrides:

toString in class Object

clone

public ObjIdBiMultiMap clone()

Clone this instance.

Overrides:

clone in class Object