java.lang.Object
- java.util.AbstractCollection<E>
- - java.util.AbstractSet<Long>
  - - org.apache.activemq.artemis.utils.collections.LongHashSet

All Implemented Interfaces:

Serializable, Iterable<Long>, Collection<Long>, Set<Long>
```
public class LongHashSet
extends AbstractSet<Long>
implements Serializable
```
A hash set implementation of Set<Long> that uses open addressing values. To minimize the memory footprint, this class uses open addressing rather than chaining. Collisions are resolved using linear probing. Deletions implement compaction, so cost of remove can approach O(N) for full maps, which makes a small loadFactor recommended. The implementation is based on Agrona IntHashSet but uses long primitive keys and a different MISSING_VALUE to account for Long.hashCode() being 0 for -1.

See Also:

Serialized Form

Nested Class Summary

Nested Classes
Modifier and Type Class Description

class LongHashSet.LongIterator
Iterator which supports unboxed access to values.

Field Summary

Fields
Modifier and Type Field Description

static int DEFAULT_INITIAL_CAPACITY
The initial capacity used when none is specified in the constructor.

static float DEFAULT_LOAD_FACTOR

Constructor Summary

Constructors
Constructor	Description
`LongHashSet()`	Construct a hash set with `DEFAULT_INITIAL_CAPACITY` and `DEFAULT_LOAD_FACTOR`.
`LongHashSet(int proposedCapacity)`	Construct a hash set with a proposed capacity and `DEFAULT_LOAD_FACTOR`.
`LongHashSet(int proposedCapacity, float loadFactor)`	Construct a hash set with a proposed initial capacity and load factor.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`boolean`	`add(long value)`	Primitive specialised overload of {this#add(Long)}
`boolean`	`add(Long value)`
`boolean`	`addAll(Collection<? extends Long> coll)`
`int`	`capacity()`	Get the total capacity for the set to which the load factor with be a fraction of.
`void`	`clear()`
`void`	`compact()`	Compact the backing arrays by rehashing with a capacity just larger than current size and giving consideration to the load factor.
`boolean`	`contains(long value)`	Contains method that does not box values.
`boolean`	`contains(Object value)`
`boolean`	`containsAll(LongHashSet other)`	LongHashSet specialised variant of {this#containsAll(Collection)}.
`boolean`	`equals(Object other)`
`int`	`hashCode()`
`boolean`	`isEmpty()`
`LongHashSet.LongIterator`	`iterator()`
`float`	`loadFactor()`	Get the load factor beyond which the set will increase size.
`boolean`	`remove(long value)`	An int specialised version of {this#remove(Object)}.
`boolean`	`remove(Object value)`
`boolean`	`removeAll(Collection<?> coll)`
`int`	`resizeThreshold()`	Get the actual threshold which when reached the map will resize.
`int`	`size()`
`Object[]`	`toArray()`
`<E> E[]`	`toArray(E[] a)`
`String`	`toString()`

Methods inherited from class java.util.AbstractCollection
containsAll, retainAll

Methods inherited from class java.lang.Object
clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface java.util.Collection
parallelStream, removeIf, stream, toArray

Methods inherited from interface java.lang.Iterable
forEach

Methods inherited from interface java.util.Set
containsAll, retainAll, spliterator

- Field Detail
  - DEFAULT_INITIAL_CAPACITY
```
public static final int DEFAULT_INITIAL_CAPACITY
```
    The initial capacity used when none is specified in the constructor.
    
    See Also:
    
    Constant Field Values
  - DEFAULT_LOAD_FACTOR
```
public static final float DEFAULT_LOAD_FACTOR
```
    See Also:
    
    Constant Field Values
- Constructor Detail
  - LongHashSet
```
public LongHashSet()
```
    Construct a hash set with DEFAULT_INITIAL_CAPACITY and DEFAULT_LOAD_FACTOR.
  - LongHashSet
```
public LongHashSet(int proposedCapacity)
```
    Construct a hash set with a proposed capacity and DEFAULT_LOAD_FACTOR.
    
    Parameters:
    
    proposedCapacity - for the initial capacity of the set.
  - LongHashSet
```
public LongHashSet(int proposedCapacity,
                   float loadFactor)
```
    Construct a hash set with a proposed initial capacity and load factor.
    
    Parameters:
    
    proposedCapacity - for the initial capacity of the set.
    
    loadFactor - to be used for resizing.
- Method Detail
  - loadFactor
```
public float loadFactor()
```
    Get the load factor beyond which the set will increase size.
    
    Returns:
    
    load factor for when the set should increase size.
  - capacity
```
public int capacity()
```
    Get the total capacity for the set to which the load factor with be a fraction of.
    
    Returns:
    
    the total capacity for the set.
  - resizeThreshold
```
public int resizeThreshold()
```
    Get the actual threshold which when reached the map will resize. This is a function of the current capacity and load factor.
    
    Returns:
    
    the threshold when the map will resize.
  - add
```
public boolean add(Long value)
```
    Specified by:
    
    add in interface Collection<Long>
    
    Specified by:
    
    add in interface Set<Long>
    
    Overrides:
    
    add in class AbstractCollection<Long>
  - add
```
public boolean add(long value)
```
    Primitive specialised overload of {this#add(Long)}
    
    Parameters:
    
    value - the value to add
    
    Returns:
    
    true if the collection has changed, false otherwise
    
    Throws:
    
    IllegalArgumentException - if value is missingValue
  - remove
```
public boolean remove(Object value)
```
    Specified by:
    
    remove in interface Collection<Long>
    
    Specified by:
    
    remove in interface Set<Long>
    
    Overrides:
    
    remove in class AbstractCollection<Long>
  - remove
```
public boolean remove(long value)
```
    An int specialised version of {this#remove(Object)}.
    
    Parameters:
    
    value - the value to remove
    
    Returns:
    
    true if the value was present, false otherwise
  - compact
```
public void compact()
```
    Compact the backing arrays by rehashing with a capacity just larger than current size and giving consideration to the load factor.
  - contains
```
public boolean contains(Object value)
```
    Specified by:
    
    contains in interface Collection<Long>
    
    Specified by:
    
    contains in interface Set<Long>
    
    Overrides:
    
    contains in class AbstractCollection<Long>
  - contains
```
public boolean contains(long value)
```
    Contains method that does not box values.
    
    Parameters:
    
    value - to be check for if the set contains it.
    
    Returns:
    
    true if the value is contained in the set otherwise false.
    
    See Also:
    
    Collection.contains(Object)
  - size
```
public int size()
```
    Specified by:
    
    size in interface Collection<Long>
    
    Specified by:
    
    size in interface Set<Long>
    
    Specified by:
    
    size in class AbstractCollection<Long>
  - isEmpty
```
public boolean isEmpty()
```
    Specified by:
    
    isEmpty in interface Collection<Long>
    
    Specified by:
    
    isEmpty in interface Set<Long>
    
    Overrides:
    
    isEmpty in class AbstractCollection<Long>
  - clear
```
public void clear()
```
    Specified by:
    
    clear in interface Collection<Long>
    
    Specified by:
    
    clear in interface Set<Long>
    
    Overrides:
    
    clear in class AbstractCollection<Long>
  - addAll
```
public boolean addAll(Collection<? extends Long> coll)
```
    Specified by:
    
    addAll in interface Collection<Long>
    
    Specified by:
    
    addAll in interface Set<Long>
    
    Overrides:
    
    addAll in class AbstractCollection<Long>
  - removeAll
```
public boolean removeAll(Collection<?> coll)
```
    Specified by:
    
    removeAll in interface Collection<Long>
    
    Specified by:
    
    removeAll in interface Set<Long>
    
    Overrides:
    
    removeAll in class AbstractSet<Long>
  - iterator
```
public LongHashSet.LongIterator iterator()
```
    Specified by:
    
    iterator in interface Collection<Long>
    
    Specified by:
    
    iterator in interface Iterable<Long>
    
    Specified by:
    
    iterator in interface Set<Long>
    
    Specified by:
    
    iterator in class AbstractCollection<Long>
  - toString
```
public String toString()
```
    Overrides:
    
    toString in class AbstractCollection<Long>
  - toArray
```
public <E> E[] toArray(E[] a)
```
    Specified by:
    
    toArray in interface Collection<Long>
    
    Specified by:
    
    toArray in interface Set<Long>
    
    Overrides:
    
    toArray in class AbstractCollection<Long>
  - toArray
```
public Object[] toArray()
```
    Specified by:
    
    toArray in interface Collection<Long>
    
    Specified by:
    
    toArray in interface Set<Long>
    
    Overrides:
    
    toArray in class AbstractCollection<Long>
  - containsAll
```
public boolean containsAll(LongHashSet other)
```
    LongHashSet specialised variant of {this#containsAll(Collection)}.
    
    Parameters:
    
    other - int hash set to compare against.
    
    Returns:
    
    true if every element in other is in this.
  - equals
```
public boolean equals(Object other)
```
    Specified by:
    
    equals in interface Collection<Long>
    
    Specified by:
    
    equals in interface Set<Long>
    
    Overrides:
    
    equals in class AbstractSet<Long>
  - hashCode
```
public int hashCode()
```
    Specified by:
    
    hashCode in interface Collection<Long>
    
    Specified by:
    
    hashCode in interface Set<Long>
    
    Overrides:
    
    hashCode in class AbstractSet<Long>

Modifier and Type	Field	Description
`static int`	`DEFAULT_INITIAL_CAPACITY`	The initial capacity used when none is specified in the constructor.
`static float`	`DEFAULT_LOAD_FACTOR`

Class LongHashSet

Nested Class Summary

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.util.AbstractCollection

Methods inherited from class java.lang.Object

Methods inherited from interface java.util.Collection

Methods inherited from interface java.lang.Iterable

Methods inherited from interface java.util.Set

Field Detail

DEFAULT_INITIAL_CAPACITY

DEFAULT_LOAD_FACTOR

Constructor Detail

LongHashSet

LongHashSet

LongHashSet

Method Detail

loadFactor

capacity

resizeThreshold

add

add

remove

remove

compact

contains

contains

size

isEmpty

clear

addAll

removeAll

iterator

toString

toArray

toArray

containsAll

equals

hashCode