EvictableCache (Helidon 0.9.1 API)

java.lang.Object
- io.helidon.security.providers.EvictableCache<K,V>

Type Parameters:

K - type of keys in this cache

V - type of values in this cache
```
public final class EvictableCache<K,V>
extends Object
```
Generic cache with eviction and max size.

Nested Class Summary

Nested Classes
Modifier and Type Class Description

static class EvictableCache.Builder<K,V>
Builder to create instances of EvictableCache.

Nested Classes
Modifier and Type	Class	Description
`static class`	`EvictableCache.Builder<K,V>`	Builder to create instances of `EvictableCache`.

Field Summary

Fields
Modifier and Type	Field	Description
`static long`	`CACHE_EVICT_DELAY_MINUTES`	Default eviction delay in minutes (how long to wait after the cache is started).
`static long`	`CACHE_EVICT_PERIOD_MINUTES`	Default eviction period in minutes (how often to evict records).
`static long`	`CACHE_MAX_SIZE`	Maximal number of records in the cache.
`static long`	`CACHE_TIMEOUT_MINUTES`	Default timeout of records in minutes (inactivity timeout).
`static long`	`EVICT_PARALLELISM_THRESHOLD`	Parameter to `ConcurrentHashMap.forEachKey(long, Consumer)` used for eviction.
`static int`	`EVICT_THREAD_COUNT`	Number of threads in the scheduled thread pool to evict records.

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`static <K,V> EvictableCache.Builder<K,V>`	`builder()`	Create a new builder for a cache.
`void`	`close()`	Close this cache.
`Optional<V>`	`computeValue(K key, Supplier<Optional<V>> valueSupplier)`	Either return a cached value or compute it and cache it.
`static <K,V> EvictableCache<K,V>`	`create()`	Create a new cache with default values.
`Optional<V>`	`get(K key)`	Get current cached value if valid.
`Optional<V>`	`remove(K key)`	Remove a key from the cache.
`int`	`size()`	Current size of the cache.

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

- Field Detail
  - EVICT_THREAD_COUNT
```
public static final int EVICT_THREAD_COUNT
```
    Number of threads in the scheduled thread pool to evict records.
    
    See Also:
    
    Constant Field Values
  - CACHE_TIMEOUT_MINUTES
```
public static final long CACHE_TIMEOUT_MINUTES
```
    Default timeout of records in minutes (inactivity timeout).
    
    See Also:
    
    Constant Field Values
  - CACHE_EVICT_PERIOD_MINUTES
```
public static final long CACHE_EVICT_PERIOD_MINUTES
```
    Default eviction period in minutes (how often to evict records).
    
    See Also:
    
    Constant Field Values
  - CACHE_EVICT_DELAY_MINUTES
```
public static final long CACHE_EVICT_DELAY_MINUTES
```
    Default eviction delay in minutes (how long to wait after the cache is started).
    
    See Also:
    
    Constant Field Values
  - CACHE_MAX_SIZE
```
public static final long CACHE_MAX_SIZE
```
    Maximal number of records in the cache. If the cache is full, no caching is done and the supplier of value is called for every uncached value.
    
    See Also:
    
    Constant Field Values
  - EVICT_PARALLELISM_THRESHOLD
```
public static final long EVICT_PARALLELISM_THRESHOLD
```
    Parameter to ConcurrentHashMap.forEachKey(long, Consumer) used for eviction.
    
    See Also:
    
    Constant Field Values
- Method Detail
  - builder
```
public static <K,V> EvictableCache.Builder<K,V> builder()
```
    Create a new builder for a cache.
    
    Type Parameters:
    
    K - type of keys in the cache
    
    V - type of values in the cache
    
    Returns:
    
    a builder to build the cache
  - create
```
public static <K,V> EvictableCache<K,V> create()
```
    Create a new cache with default values.
    
    Type Parameters:
    
    K - type of keys in the cache
    
    V - type of values in the cache
    
    Returns:
    
    new cache built with default values
  - remove
```
public Optional<V> remove(K key)
```
    Remove a key from the cache. Return the value if it was cached and valid.
    
    Parameters:
    
    key - key to remove
    
    Returns:
    
    value if it was removed and valid, empty otherwise
  - get
```
public Optional<V> get(K key)
```
    Get current cached value if valid.
    
    Parameters:
    
    key - key to use
    
    Returns:
    
    current value in the cache or empty if not present (or invalid)
  - size
```
public int size()
```
    Current size of the cache. As this cache is using ConcurrentHashMap as backing store, be aware that this value is not guaranteed to be consistent, as puts and removed may be happening in parallel.
    
    Returns:
    
    current size of the cache (including valid and invalid - not yet evicted - values)
  - computeValue
```
public Optional<V> computeValue(K key,
                                Supplier<Optional<V>> valueSupplier)
```
    Either return a cached value or compute it and cache it.
    
    Parameters:
    
    key - key to check/insert value for
    
    valueSupplier - supplier called if the value is not yet cached, or is invalid
    
    Returns:
    
    current value from the cache, or computed value from the supplier
  - close
```
public void close()
```
    Close this cache. Cancels eviction future and clears the cache.

Class EvictableCache<K,V>

Nested Class Summary

Field Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

EVICT_THREAD_COUNT

CACHE_TIMEOUT_MINUTES

CACHE_EVICT_PERIOD_MINUTES

CACHE_EVICT_DELAY_MINUTES

CACHE_MAX_SIZE

EVICT_PARALLELISM_THRESHOLD

Method Detail

builder

create

remove

get

size

computeValue

close