Package org.apache.pdfbox.util

Class SmallMap<K,V>

java.lang.Object

org.apache.pdfbox.util.SmallMap<K,V>

All Implemented Interfaces:

Map<K,V>

public class SmallMap<K,V>
extends Object
implements Map<K,V>

Map implementation with a smallest possible memory usage. It should only be used for maps with small number of items (e.g. <30) since most operations have an O(n) complexity. Thus it should be used in cases with large number of map objects, each having only few items.

null is not supported for keys or values.

Nested Class Summary

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

Map.Entry<K,V>

Constructor Summary

Constructors

Constructor	Description
SmallMap()	Creates empty map.
SmallMap(Map<? extends K,? extends V> initMap)	Creates map filled with entries from provided map.

Method Summary

Modifier and Type	Method	Description
void	clear()
boolean	containsKey(Object key)
boolean	containsValue(Object value)
Set<Map.Entry<K,V>>	entrySet()
V	get(Object key)
boolean	isEmpty()
Set<K>	keySet()	Returns a set view of the keys contained in this map.
V	put(K key, V value)
final void	putAll(Map<? extends K,? extends V> otherMap)
V	remove(Object key)
int	size()
Collection<V>	values()	Returns a collection of the values contained in this map.

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 Details

SmallMap

public SmallMap()

Creates empty map.

SmallMap

public SmallMap(Map<? extends K,? extends V> initMap)

Creates map filled with entries from provided map.

Method Details

size

public int size()

Specified by:

size in interface Map<K,V>

isEmpty

public boolean isEmpty()

Specified by:

isEmpty in interface Map<K,V>

containsKey

public boolean containsKey(Object key)

Specified by:

containsKey in interface Map<K,V>

containsValue

public boolean containsValue(Object value)

Specified by:

containsValue in interface Map<K,V>

get

public V get(Object key)

Specified by:

get in interface Map<K,V>

put

public V put(K key,
 V value)

Specified by:

put in interface Map<K,V>

remove

public V remove(Object key)

Specified by:

remove in interface Map<K,V>

putAll

public final void putAll(Map<? extends K,? extends V> otherMap)

Specified by:

putAll in interface Map<K,V>

clear

public void clear()

Specified by:

clear in interface Map<K,V>

keySet

public Set<K> keySet()

Returns a set view of the keys contained in this map.

The current implementation does not allow changes to the returned key set (which would have to be reflected in the underlying map.

Specified by:

keySet in interface Map<K,V>

values

public Collection<V> values()

Returns a collection of the values contained in this map.

The current implementation does not allow changes to the returned collection (which would have to be reflected in the underlying map.

Specified by:

values in interface Map<K,V>

entrySet

public Set<Map.Entry<K,V>> entrySet()

Specified by:

entrySet in interface Map<K,V>