Package com.opencloud.util

Class IntSet

java.lang.Object

com.opencloud.util.IntSet

All Implemented Interfaces:

FastSerializable, Serializable, Cloneable, Iterable<Integer>

public class IntSet
extends Object
implements Cloneable, Serializable, FastSerializable, Iterable<Integer>

IntSet provides efficient management of a set of primitive integers. The underlying storage is an int[]. IntSet tries to avoid reallocating storage where possible.

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor	Description
IntSet()	Construct a new empty set.
IntSet(int capacity)	Construct a new empty set, with the given initial allocation size
IntSet(int[] fromData)	Construct a set from an integer array.
IntSet(int[] fromData, boolean sorted)	Construct a set from an integer array.
IntSet(IntSet fromSet)	Construct a copy of an IntSet.
IntSet(DataInput inStream)	FastSerializable constructor.
IntSet(String str)	Construct a set from a toString() representation

Method Summary

Modifier and Type	Method	Description
boolean	add(int val)	Add a value to the set.
IntSet	addAll(int[] vals)	Add an array of values to the set.
IntSet	addAll(IntSet other)	Add the values from another IntSet to this set.
StringBuffer	appendToStringBuffer(StringBuffer sb)	Appends a textual representation of this IntSet to the given StringBuffer.
void	clear()	Sets this IntSet to represent the empty set.
IntSet	clone()	Performs a deep copy of the set.
static IntSet	complement(IntSet superset, IntSet subset)	Return a new set that is the complement of a subset within a superset.
boolean	contains(int val)	Check if a value is contained in the set.
boolean	containsAll(int[] vals)	Check if the given values are contained in the set.
boolean	containsAll(IntSet other)	Check if the given values are contained in this set.
static IntSet	copyOf(int[] from)	Construct a new set that contains the given values.
static IntSet	copyOf(Set<Integer> fromSet)	Construct a new set that contains a copy of the values in the given set.
static IntSet	emptySet()	Construct a new empty set.
boolean	equals(Object other)	Set equality.
void	fromArray(int[] fromData)	Sets the integers in this IntSet to be those in the given array.
void	fromArray(int[] fromData, boolean sorted)	Sets the integers in this IntSet to be those in the given array.
int	get(int index)	Get the value at a specified index.
int	hashCode()	Computes a hash code value for this object.
static IntSet	intersection(IntSet setA, IntSet setB)	Return a new set that is the intersection of two other sets.
boolean	isEmpty()	Determines whether this IntSet represents an empty set.
boolean	isSubsetOf(IntSet superset)	Determines whether this IntSet is a subset of the given IntSet.
boolean	isSupersetOf(IntSet subset)	Determines whether this IntSet is a superset of the given IntSet.
Iterator<Integer>	iterator()
int	lowestMember()	Gets the smallest valued int from this IntSet.
static IntSet	of(int... values)	Construct a set with the given values.
boolean	remove(int val)	Remove a value from the set.
IntSet	removeAll(int[] vals)	Remove an array of values to the set.
IntSet	removeAll(IntSet other)	Remove all values in the provided IntSet from this set.
int	size()	Gets the size of this IntSet.
int[]	toArray()	Return an array containing only the set data (sorted).
void	toStream(DataOutput outStream)	Serialize the state of this object to a stream.
String	toString()	Returns a textual representation of this IntSet.
static IntSet	union(IntSet setA, IntSet setB)	Return a new set that is the union of two other sets.

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.lang.Iterable

forEach, spliterator

Constructor Detail

IntSet

public IntSet()

Construct a new empty set.

IntSet

public IntSet(int capacity)

Construct a new empty set, with the given initial allocation size

Parameters:

capacity - the initial storage capacity to use; may be adjusted if too small.

IntSet

public IntSet(IntSet fromSet)

Construct a copy of an IntSet.

Parameters:

fromSet - the set to copy

IntSet

public IntSet(int[] fromData,
              boolean sorted)

Construct a set from an integer array.

Parameters:

fromData - the initial contents of the set; not modified

sorted - if true, fromArray is assumed to be already sorted

IntSet

public IntSet(int[] fromData)

Construct a set from an integer array.

Parameters:

fromData - an array holding the initial set contents; assumed to be unsorted.

IntSet

public IntSet(DataInput inStream)
       throws IOException

FastSerializable constructor.

Throws:

IOException

IntSet

public IntSet(String str)
       throws IllegalArgumentException

Construct a set from a toString() representation

Throws:

IllegalArgumentException

Method Detail

of

public static IntSet of(int... values)

Construct a set with the given values. This is a separate static method to avoid confusion with the single-int ctor variant.

Parameters:

values - values to include in the new set

Returns:

a new IntSet

emptySet

public static IntSet emptySet()

Construct a new empty set. Equivalent to "new IntSet()" but reads a little more nicely.

Returns:

a new empty IntSet

copyOf

public static IntSet copyOf(int[] from)

Construct a new set that contains the given values.

Parameters:

from - an array of unsorted values

Returns:

a new IntSet

copyOf

public static IntSet copyOf(Set<Integer> fromSet)

Construct a new set that contains a copy of the values in the given set.

Parameters:

fromSet - a set of Integers

Returns:

a new IntSet

clone

public IntSet clone()

Performs a deep copy of the set.

Overrides:

clone in class Object

toStream

public void toStream(DataOutput outStream)
              throws IOException

Description copied from interface: FastSerializable

Serialize the state of this object to a stream.

Specified by:

toStream in interface FastSerializable

Parameters:

outStream - the stream to serialize to.

Throws:

IOException - if an error occurs during serialization

equals

public boolean equals(Object other)

Set equality.

Overrides:

equals in class Object

hashCode

public int hashCode()

Computes a hash code value for this object.

Overrides:

hashCode in class Object

Returns:

int hash code

isEmpty

public boolean isEmpty()

Determines whether this IntSet represents an empty set.

Returns:

whether size of set is 0

add

public boolean add(int val)

Add a value to the set.

Parameters:

val - the value to add

Returns:

true if the value was not already present

addAll

public IntSet addAll(int[] vals)

Add an array of values to the set.

Parameters:

vals - the values to add.

Returns:

this IntSet

addAll

public IntSet addAll(IntSet other)

Add the values from another IntSet to this set.

Parameters:

other - the set of values to add.

Returns:

this IntSet.

remove

public boolean remove(int val)

Remove a value from the set.

Parameters:

val - the value to remove

Returns:

true if the value was present (and removed)

removeAll

public IntSet removeAll(int[] vals)

Remove an array of values to the set.

Parameters:

vals - the values to remove.

Returns:

this IntSet

removeAll

public IntSet removeAll(IntSet other)

Remove all values in the provided IntSet from this set.

Parameters:

other - the set of values to remove from this set.

Returns:

this IntSet.

contains

public boolean contains(int val)

Check if a value is contained in the set.

Parameters:

val - the value to check for

Returns:

true if val is present in the set

containsAll

public boolean containsAll(int[] vals)

Check if the given values are contained in the set.

Parameters:

vals - the values to check for

Returns:

true if all the values are present in the set, false otherwise

containsAll

public boolean containsAll(IntSet other)

Check if the given values are contained in this set.

Parameters:

other - the set of values to check for.

Returns:

true if all the values are present in the set, false otherwise

fromArray

public void fromArray(int[] fromData)

Sets the integers in this IntSet to be those in the given array.

Parameters:

fromData - array of ints

fromArray

public void fromArray(int[] fromData,
                      boolean sorted)

Sets the integers in this IntSet to be those in the given array.

Parameters:

fromData - array of ints

sorted - whether the ints in array fromData are in sorted sequence

clear

public void clear()

Sets this IntSet to represent the empty set.

toArray

public int[] toArray()

Return an array containing only the set data (sorted).

Returns:

a sorted array containing the set members

toString

public String toString()

Returns a textual representation of this IntSet. The textual representation is of the form [i_1, ..., i_n].

Overrides:

toString in class Object

Returns:

String

appendToStringBuffer

public StringBuffer appendToStringBuffer(StringBuffer sb)

Appends a textual representation of this IntSet to the given StringBuffer. The textual representation is of the form [i_1, ..., i_n].

Parameters:

sb - StringBuffer

Returns:

the given StringBuffer

intersection

public static IntSet intersection(IntSet setA,
                                  IntSet setB)

Return a new set that is the intersection of two other sets. O(n+m).

Parameters:

setA - the first set to intersect; null means an empty set

setB - the second set to intersect; null means an empty set

Returns:

a new set (always non-null) containing those members in both setA and setB

union

public static IntSet union(IntSet setA,
                           IntSet setB)

Return a new set that is the union of two other sets. O(n+m).

Parameters:

setA - the first set to union; null means an empty set

setB - the second set to union; null means an empty set

Returns:

a new set (always non-null) containing all members of setA and setB

complement

public static IntSet complement(IntSet superset,
                                IntSet subset)

Return a new set that is the complement of a subset within a superset. O(n+m).

Parameters:

superset - the superset to perform the complement within; null means the empty set

subset - the subset to complement; null means the empty set

Returns:

a new set (always non-null) containing all members of superset that are not in subset

isSupersetOf

public boolean isSupersetOf(IntSet subset)

Determines whether this IntSet is a superset of the given IntSet.

Parameters:

subset - the conjectured subset of this IntSet

isSubsetOf

public boolean isSubsetOf(IntSet superset)

Determines whether this IntSet is a subset of the given IntSet.

Parameters:

superset - the conjectured superset of this IntSet

size

public int size()

Gets the size of this IntSet.

Returns:

int size

lowestMember

public int lowestMember()

Gets the smallest valued int from this IntSet.

Returns:

lowest int

Throws:

NoSuchElementException - if this IntSet is empty

get

public int get(int index)
        throws ArrayIndexOutOfBoundsException

Get the value at a specified index. As the set is sorted, an index of 0 returns the smallest value in the set, an index of size() - 1 returns the highest value, and any index in between returns the corresponding value.

Parameters:

index - the index.

Returns:

the value at the index.

Throws:

ArrayIndexOutOfBoundsException - if index is less than zero or greater than or equal to the size of the set.

iterator

public Iterator<Integer> iterator()

Specified by:

iterator in interface Iterable<Integer>