Package com.blackrook.small.struct

Class HashDequeMap<K,V>

java.lang.Object

java.util.AbstractMap<K,V>

java.util.HashMap<K,Deque<V>>

com.blackrook.small.struct.HashDequeMap<K,V>

Type Parameters:

K - the key type.

V - the value type stored.

All Implemented Interfaces:

Serializable, Cloneable, Map<K,Deque<V>>

public class HashDequeMap<K,V>
extends HashMap<K,Deque<V>>

A hash map that stores deques of a particular type.

Author:

Matthew Tropiano

See Also:

• Serialized Form

Nested Class Summary

Nested classes/interfaces inherited from class java.util.AbstractMap

AbstractMap.SimpleEntry<K extends Object,V extends Object>, AbstractMap.SimpleImmutableEntry<K extends Object,V extends Object>

Nested classes/interfaces inherited from interface java.util.Map

Map.Entry<K extends Object,V extends Object>

Constructor Summary

Constructors

Constructor	Description
HashDequeMap()	Creates a new HashDequeMap that has default capacity and load factor.
HashDequeMap(int initialCapacity)	Creates a new HashDequeMap that has a specific capacity and default load factor.
HashDequeMap(int initialCapacity, float loadFactor)	Creates a new HashDequeMap that has a specific capacity and default load factor.

Method Summary

Modifier and Type	Method	Description
boolean	add(K key, V value)	Adds a value to the end of a deque.
void	addFirst(K key, V value)	Adds a value to the beginning of a deque.
void	addLast(K key, V value)	Adds a value to the end of a deque.
protected Deque<V>	create()	Called to create a new Deque implementation that gets stored in the table.
V	peekFirst(K key)	Returns the value at the beginning of a deque.
V	peekLast(K key)	Returns the value at the end of a deque.
V	poll(K key)	Removes a value from the front of a deque.
V	pollFirst(K key)	Removes a value from the beginning of a deque.
V	pollLast(K key)	Removes a value from the end of a deque.
V	pop(K key)	Removes a value from the front of a deque.
void	push(K key, V value)	Adds a value to the front of a deque.
V	removeFirst(K key)	Removes a value from the beginning of a deque.
V	removeLast(K key)	Removes a value from the end of a deque.
boolean	removeValue(K key, V value)	Removes a value from a deque.

Methods inherited from class java.util.HashMap

clear, clone, compute, computeIfAbsent, computeIfPresent, containsKey, containsValue, entrySet, forEach, get, getOrDefault, isEmpty, keySet, merge, put, putAll, putIfAbsent, remove, remove, replace, replace, replaceAll, size, values

Methods inherited from class java.util.AbstractMap

equals, hashCode, toString

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.util.Map

equals, hashCode

Constructor Details

HashDequeMap

public HashDequeMap()

Creates a new HashDequeMap that has default capacity and load factor.

HashDequeMap

public HashDequeMap(int initialCapacity)

Creates a new HashDequeMap that has a specific capacity and default load factor.

Parameters:

initialCapacity - the initial capacity.

HashDequeMap

public HashDequeMap(int initialCapacity,
 float loadFactor)

Creates a new HashDequeMap that has a specific capacity and default load factor.

Parameters:

initialCapacity - the initial capacity.

loadFactor - the load factor.

Method Details

create

protected Deque<V> create()

Called to create a new Deque implementation that gets stored in the table. By default, this calls new LinkedList%lt;>().

Returns:

a new deque.

addFirst

public void addFirst(K key,
 V value)

Adds a value to the beginning of a deque. If no corresponding deque, this creates a new deque.

Parameters:

key - the key.

value - the value.

See Also:

• Deque.addFirst(Object)

addLast

public void addLast(K key,
 V value)

Adds a value to the end of a deque. If no corresponding deque, this creates a new deque.

Parameters:

key - the key.

value - the value.

See Also:

• Deque.addLast(Object)

removeFirst

public V removeFirst(K key)

Removes a value from the beginning of a deque. If no corresponding deque, this throws an exception.

Parameters:

key - the key.

Returns:

the element removed.

Throws:

NoSuchElementException - if the key does not correspond to an existing deque.

See Also:

• Deque.removeFirst()

removeLast

public V removeLast(K key)

Removes a value from the end of a deque. If no corresponding deque, this throws an exception.

Parameters:

key - the key.

Returns:

the element removed.

Throws:

NoSuchElementException - if the key does not correspond to an existing deque.

See Also:

• Deque.removeLast()

pollFirst

public V pollFirst(K key)

Removes a value from the beginning of a deque. If no corresponding deque, this returns null.

Parameters:

key - the key.

Returns:

the element removed, or null if no element.

See Also:

• Deque.pollFirst()

pollLast

public V pollLast(K key)

Removes a value from the end of a deque. If no corresponding deque, this returns null.

Parameters:

key - the key.

Returns:

the element removed, or null if no element.

See Also:

• Deque.pollLast()

peekFirst

public V peekFirst(K key)

Returns the value at the beginning of a deque. If no corresponding deque, this returns null.

Parameters:

key - the key.

Returns:

the element found, or null if no element.

See Also:

• Deque.peekFirst()

peekLast

public V peekLast(K key)

Returns the value at the end of a deque. If no corresponding deque, this returns null.

Parameters:

key - the key.

Returns:

the element found, or null if no element.

See Also:

• Deque.peekLast()

add

public boolean add(K key,
 V value)

Adds a value to the end of a deque. If no corresponding deque, this creates a new deque.

Parameters:

key - the key.

value - the value.

Returns:

true (as specified by Collection.add(Object))

See Also:

• Deque.add(Object)

removeValue

public boolean removeValue(K key,
 V value)

Removes a value from a deque. If no corresponding deque, this returns false.

Parameters:

key - the key.

value - the value to remove.

Returns:

true if an element was removed as a result of this call

Throws:

ClassCastException - if the class of the specified element is incompatible with the deque (optional)

NullPointerException - if the specified element is null and this deque does not permit null elements (optional)

See Also:

• Deque.remove(Object)

pop

public V pop(K key)

Removes a value from the front of a deque. If no corresponding deque, this throws an exception.

Parameters:

key - the key.

Returns:

the element removed.

Throws:

NoSuchElementException - if the key does not correspond to an existing deque.

See Also:

• Deque.pop()

poll

public V poll(K key)

Removes a value from the front of a deque. If no corresponding deque, this returns null.

Parameters:

key - the key.

Returns:

the element removed, or null if no element.

See Also:

• Deque.poll()

push

public void push(K key,
 V value)

Adds a value to the front of a deque. If no corresponding deque, this creates it.

Parameters:

key - the key.

value - the value.

See Also:

• Deque.push(Object)