CopyOnWriteHashMap (vespajlib 7.248.5 API)

java.lang.Object
- java.util.AbstractMap<K,V>
- - com.yahoo.collections.CopyOnWriteHashMap<K,V>

All Implemented Interfaces:

java.lang.Cloneable, java.util.Map<K,V>
```
public class CopyOnWriteHashMap<K,V>
extends java.util.AbstractMap<K,V>
implements java.lang.Cloneable
```
A hashmap wrapper which defers cloning of the enclosed map until it is written. Use this to make clones cheap in maps which are often not further modified.
As with regular maps, this can only be used safely if the content of the map is immutable. If not, the copyMap(java.util.Map<K, V>) method can be overridden to perform a deep clone.

Author:

bratseth

Nested Class Summary
- Nested classes/interfaces inherited from class java.util.AbstractMap
  java.util.AbstractMap.SimpleEntry<K extends java.lang.Object,V extends java.lang.Object>, java.util.AbstractMap.SimpleImmutableEntry<K extends java.lang.Object,V extends java.lang.Object>
- Nested classes/interfaces inherited from interface java.util.Map
  java.util.Map.Entry<K extends java.lang.Object,V extends java.lang.Object>

Constructor Summary

Constructors
Constructor Description

CopyOnWriteHashMap()

CopyOnWriteHashMap(int capacity)

CopyOnWriteHashMap(java.util.Map<K,V> map)

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`CopyOnWriteHashMap<K,V>`	`clone()`
`protected java.util.Map<K,V>`	`copyMap(java.util.Map<K,V> original)`	Make a copy of the given map with the requisite deepness.
`java.util.Set<java.util.Map.Entry<K,V>>`	`entrySet()`
`V`	`put(K key, V value)`
`V`	`remove(java.lang.Object key)`	Override to avoid using iterator.remove

Methods inherited from class java.util.AbstractMap
clear, containsKey, containsValue, equals, get, hashCode, isEmpty, keySet, putAll, size, toString, values

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

Methods inherited from interface java.util.Map
compute, computeIfAbsent, computeIfPresent, forEach, getOrDefault, merge, putIfAbsent, remove, replace, replace, replaceAll

- Constructor Detail
  - CopyOnWriteHashMap
```
public CopyOnWriteHashMap()
```
  - CopyOnWriteHashMap
```
public CopyOnWriteHashMap(int capacity)
```
  - CopyOnWriteHashMap
```
public CopyOnWriteHashMap(java.util.Map<K,V> map)
```
- Method Detail
  - copyMap
```
protected java.util.Map<K,V> copyMap(java.util.Map<K,V> original)
```
    Make a copy of the given map with the requisite deepness. This default implementation does return new HashMap<>(original);
  - clone
```
public CopyOnWriteHashMap<K,V> clone()
```
    Overrides:
    
    clone in class java.util.AbstractMap<K,V>
  - entrySet
```
public java.util.Set<java.util.Map.Entry<K,V>> entrySet()
```
    Specified by:
    
    entrySet in interface java.util.Map<K,V>
    
    Specified by:
    
    entrySet in class java.util.AbstractMap<K,V>
  - put
```
public V put(K key,
             V value)
```
    Specified by:
    
    put in interface java.util.Map<K,V>
    
    Overrides:
    
    put in class java.util.AbstractMap<K,V>
  - remove
```
public V remove(java.lang.Object key)
```
    Override to avoid using iterator.remove
    
    Specified by:
    
    remove in interface java.util.Map<K,V>
    
    Overrides:
    
    remove in class java.util.AbstractMap<K,V>