HashGenMap (SwimOS)

java.lang.Object
- swim.util.HashGenMap<K,V>

```
public class HashGenMap<K,V>
extends Object
```
A hashed generational map evicts the least recently used value with the worst hit rate per hash bucket. HashGenMap is a concurrent and lock-free LRFU cache, with O(1) access time, that strongly references its values.
Maintaining four "generations" of cached values per hash bucket, the cache discards from the younger generations based on least recent usage, and promotes younger generations to older generations based on most frequent usage. Cache misses count as negative usage of the older generations, biasing the cache against least recently used values with poor hit rates.
The evict(K, V) method is guaranteed to be called when a value is displaced from the cache.

Constructor Summary

Constructors
Constructor Description

HashGenMap(int size)

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`void`	`clear()`
`protected void`	`evict(K key, V value)`
`V`	`get(K key)`
`double`	`hitRatio()`
`V`	`put(K key, V value)`
`V`	`remove(K key)`

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail
- HashGenMap
```
public HashGenMap(int size)
```

Method Detail

evict

protected void evict(K key,
                     V value)

get
```
public V get(K key)
```

put

public V put(K key,
             V value)

remove
```
public V remove(K key)
```

clear
```
public void clear()
```

hitRatio
```
public double hitRatio()
```