Package org.apache.commons.math.util

Class OpenIntToFieldHashMap<T extends FieldElement<T>>

java.lang.Object

org.apache.commons.math.util.OpenIntToFieldHashMap<T>

Type Parameters:

T - the type of the field elements

All Implemented Interfaces:

Serializable

public class OpenIntToFieldHashMap<T extends FieldElement<T>>
extends Object
implements Serializable

Open addressed map from int to FieldElement.

This class provides a dedicated map from integers to FieldElements with a much smaller memory overhead than standard java.util.Map.

This class is not synchronized. The specialized iterators returned by iterator() are fail-fast: they throw a ConcurrentModificationException when they detect the map has been modified during iteration.

Since:

2.0

See Also:

• Serialized Form

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
class	OpenIntToFieldHashMap.Iterator	Iterator class for the map.

Constructor Summary

Constructors

Constructor	Description
OpenIntToFieldHashMap(Field<T> field)	Build an empty map with default size and using zero for missing entries.
OpenIntToFieldHashMap(Field<T> field, int expectedSize)	Build an empty map with specified size and using zero for missing entries.
OpenIntToFieldHashMap(Field<T> field, int expectedSize, T missingEntries)	Build an empty map with specified size.
OpenIntToFieldHashMap(Field<T> field, T missingEntries)	Build an empty map with default size
OpenIntToFieldHashMap(OpenIntToFieldHashMap<T> source)	Copy constructor.

Method Summary

Modifier and Type	Method	Description
boolean	containsKey(int key)	Check if a value is associated with a key.
T	get(int key)	Get the stored value associated with the given key
OpenIntToFieldHashMap<T>.Iterator	iterator()	Get an iterator over map elements.
T	put(int key, T value)	Put a value associated with a key in the map.
T	remove(int key)	Remove the value associated with a key.
int	size()	Get the number of elements stored in the map.

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Details

OpenIntToFieldHashMap

public OpenIntToFieldHashMap(Field<T> field)

Build an empty map with default size and using zero for missing entries.

Parameters:

field - field to which the elements belong

OpenIntToFieldHashMap

public OpenIntToFieldHashMap(Field<T> field,
 T missingEntries)

Build an empty map with default size

Parameters:

field - field to which the elements belong

missingEntries - value to return when a missing entry is fetched

OpenIntToFieldHashMap

public OpenIntToFieldHashMap(Field<T> field,
 int expectedSize)

Build an empty map with specified size and using zero for missing entries.

Parameters:

field - field to which the elements belong

expectedSize - expected number of elements in the map

OpenIntToFieldHashMap

public OpenIntToFieldHashMap(Field<T> field,
 int expectedSize,
 T missingEntries)

Build an empty map with specified size.

Parameters:

field - field to which the elements belong

expectedSize - expected number of elements in the map

missingEntries - value to return when a missing entry is fetched

OpenIntToFieldHashMap

public OpenIntToFieldHashMap(OpenIntToFieldHashMap<T> source)

Copy constructor.

Parameters:

source - map to copy

Method Details

get

public T get(int key)

Get the stored value associated with the given key

Parameters:

key - key associated with the data

Returns:

data associated with the key

containsKey

public boolean containsKey(int key)

Check if a value is associated with a key.

Parameters:

key - key to check

Returns:

true if a value is associated with key

iterator

public OpenIntToFieldHashMap<T>.Iterator iterator()

Get an iterator over map elements.

The specialized iterators returned are fail-fast: they throw a ConcurrentModificationException when they detect the map has been modified during iteration.

Returns:

iterator over the map elements

size

public int size()

Get the number of elements stored in the map.

Returns:

number of elements stored in the map

remove

public T remove(int key)

Remove the value associated with a key.

Parameters:

key - key to which the value is associated

Returns:

removed value

put

public T put(int key,
 T value)

Put a value associated with a key in the map.

Parameters:

key - key to which value is associated

value - value to put in the map

Returns:

previous value associated with the key