de.caff.generics

Class HashCoderMap<K,V>

java.lang.Object

de.caff.generics.HashCoderMap<K,V>

Type Parameters:

K - type of hash key

V - value type

All Implemented Interfaces:

java.util.Map<K,V>

public class HashCoderMap<K,V>
extends java.lang.Object
implements java.util.Map<K,V>

A hashmap implementation that allows to provide a dedicated hashcode implementation for its elements.

Especially for mutable objects you should take care of providing a useful copier with either the HashCoder argument in HashCoderMap(HashCoder) or directly with HashCoderMap(Function).

Since:

Mai 18, 2020

Author:

Rammi

Nested Class Summary

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

java.util.Map.Entry<K,V>

Constructor Summary

Constructors

Constructor and Description
HashCoderMap(java.util.function.Function<K,K> copier) Constructor for creating a hashmap with keys created from mutable objects.
HashCoderMap(HashCodeCalculator<? super K> calculator) Constructor.
HashCoderMap(HashCodeCalculator<? super K> calculator, Matcher<? super K,? super K> matcher) Constructor.
HashCoderMap(HashCodeCalculator<? super K> calculator, Matcher<? super K,? super K> matcher, Function1<K,K> copier) Constructor.
HashCoderMap(HashCoder<K> hashCoder) Constructor.
HashCoderMap(HashCoder<K> hashCoder, int initialCapacity) Constructor.
HashCoderMap(HashCoder<K> hashCoder, int initialCapacity, float loadFactor) Constructor.
HashCoderMap(HashCoder<K> hashCoder, java.util.Map<? extends K,? extends V> sourceMap) Copy constructor.

Method Summary

Modifier and Type	Method and Description
void	clear()
boolean	containsKey(java.lang.Object key)
boolean	containsValue(java.lang.Object value)
java.util.Set<java.util.Map.Entry<K,V>>	entrySet()
V	get(java.lang.Object key)
HashCoder<? super K>	getHashCoder() Get the hash coder used in this map.
boolean	isEmpty()
java.util.Set<K>	keySet()
V	put(K key, V value)
void	putAll(java.util.Map<? extends K,? extends V> m)
V	remove(java.lang.Object key)
int	size()
java.util.Collection<V>	values()

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.util.Map

compute, computeIfAbsent, computeIfPresent, equals, forEach, getOrDefault, hashCode, merge, putIfAbsent, remove, replace, replace, replaceAll

Constructor Detail

HashCoderMap

public HashCoderMap(@NotNull
                    HashCoder<K> hashCoder)

Constructor.

Parameters:

hashCoder - hash coder used for hashcode calculation, equality checks and copying

HashCoderMap

public HashCoderMap(@NotNull
                    HashCoder<K> hashCoder,
                    int initialCapacity)

Constructor.

Parameters:

hashCoder - hash coder used for hashcode calculation, equality checks and copying

initialCapacity - initial map capacity

HashCoderMap

public HashCoderMap(@NotNull
                    HashCoder<K> hashCoder,
                    int initialCapacity,
                    float loadFactor)

Constructor.

Parameters:

hashCoder - hash coder used for hashcode calculation, equality checks and copying

initialCapacity - initial map capacity

loadFactor - map load factor

HashCoderMap

public HashCoderMap(@NotNull
                    HashCoder<K> hashCoder,
                    @NotNull
                    java.util.Map<? extends K,? extends V> sourceMap)

Copy constructor.

Parameters:

hashCoder - hash coder used for

sourceMap - source map which is copied to this map

HashCoderMap

public HashCoderMap(@NotNull
                    HashCodeCalculator<? super K> calculator)

Constructor. This uses Objects.equals(Object, Object) for equality checks.

Parameters:

calculator - hash code calculator

HashCoderMap

public HashCoderMap(@NotNull
                    HashCodeCalculator<? super K> calculator,
                    @NotNull
                    Matcher<? super K,? super K> matcher)

Constructor.

Parameters:

calculator - hash code calculator

matcher - equality checker fpr hash keys

HashCoderMap

public HashCoderMap(@NotNull
                    HashCodeCalculator<? super K> calculator,
                    @NotNull
                    Matcher<? super K,? super K> matcher,
                    @NotNull
                    Function1<K,K> copier)

Constructor.

Parameters:

calculator - hash code calculator

matcher - equality checker fpr hash keys

copier - copier for keys, useful to decouple the keys from their basically mutable source objects

HashCoderMap

public HashCoderMap(@NotNull
                    java.util.function.Function<K,K> copier)

Constructor for creating a hashmap with keys created from mutable objects. As this decouples the internally used keys from incoming and outgoing keys the basic hashmap requirements are always guaranteed.

Otherwise this uses the Object.hashCode()

Parameters:

copier - copier for keys

Method Detail

getHashCoder

@NotNull
public HashCoder<? super K> getHashCoder()

Get the hash coder used in this map.

Returns:

hash coder used for hashcode calculation, equality checks and copying

size

public int size()

Specified by:

size in interface java.util.Map<K,V>

isEmpty

public boolean isEmpty()

Specified by:

isEmpty in interface java.util.Map<K,V>

containsKey

public boolean containsKey(java.lang.Object key)

Specified by:

containsKey in interface java.util.Map<K,V>

containsValue

public boolean containsValue(java.lang.Object value)

Specified by:

containsValue in interface java.util.Map<K,V>

get

public V get(java.lang.Object key)

Specified by:

get in interface java.util.Map<K,V>

put

public V put(K key,
             V value)

Specified by:

put in interface java.util.Map<K,V>

remove

public V remove(java.lang.Object key)

Specified by:

remove in interface java.util.Map<K,V>

putAll

public void putAll(java.util.Map<? extends K,? extends V> m)

Specified by:

putAll in interface java.util.Map<K,V>

clear

public void clear()

Specified by:

clear in interface java.util.Map<K,V>

keySet

@NotNull
public java.util.Set<K> keySet()

Specified by:

keySet in interface java.util.Map<K,V>

values

@NotNull
public java.util.Collection<V> values()

Specified by:

values in interface java.util.Map<K,V>

entrySet

@NotNull
public java.util.Set<java.util.Map.Entry<K,V>> entrySet()

Specified by:

entrySet in interface java.util.Map<K,V>