Class LFUCache<K,​V>

  • All Implemented Interfaces:
    SolrInfoBean, SolrMetricProducer, SolrCache<K,​V>

    public class LFUCache<K,​V>
    extends Object
    implements SolrCache<K,​V>
    SolrCache based on ConcurrentLFUCache implementation.

    This implementation does not use a separate cleanup thread. Instead it uses the calling thread itself to do the cleanup when the size of the cache exceeds certain limits.

    Also see SolrCaching

    This API is experimental and subject to change

    solr 3.6
    See Also:
    ConcurrentLFUCache, SolrCache
    • Constructor Detail

      • LFUCache

        public LFUCache()
    • Method Detail

      • init

        public Object init​(Map args,
                           Object persistence,
                           CacheRegenerator regenerator)
        Description copied from interface: SolrCache
        The initialization routine. Instance specific arguments are passed in the args map.

        The persistence object will exist across different lifetimes of similar caches. For example, all filter caches will share the same persistence object, sometimes at the same time (it must be thread-safe). If null is passed, then the cache implementation should create and return a new persistence object. If not null, the passed in object should be returned again.

        Since it will exist across the lifetime of many caches, care should be taken to not reference any particular cache instance and prevent it from being garbage collected (no using inner classes unless they are static).

        The persistence object is designed to be used as a way for statistics to accumulate across all instances of the same type of cache, however the object may be of any type desired by the cache implementation.

        The CacheRegenerator is what the cache uses during auto-warming to regenerate an item in the new cache from an entry in the old cache.

        Specified by:
        init in interface SolrCache<K,​V>
      • name

        public String name()
        Description copied from interface: SolrCache
        Name the Cache can be referenced with by SolrRequestHandlers. This method must return the identifier that the Cache instance expects SolrRequestHandlers to use when requesting access to it from the SolrIndexSearcher. It is strongly recommended that this method return the value of the "name" parameter from the init args. :TODO: verify this.
        Specified by:
        name in interface SolrCache<K,​V>
      • size

        public int size()
        Description copied from interface: SolrCache
        :TODO: copy from Map
        Specified by:
        size in interface SolrCache<K,​V>
      • put

        public V put​(K key,
                     V value)
        Description copied from interface: SolrCache
        :TODO: copy from Map
        Specified by:
        put in interface SolrCache<K,​V>
      • get

        public V get​(K key)
        Description copied from interface: SolrCache
        :TODO: copy from Map
        Specified by:
        get in interface SolrCache<K,​V>
      • clear

        public void clear()
        Description copied from interface: SolrCache
        :TODO: copy from Map
        Specified by:
        clear in interface SolrCache<K,​V>
      • setState

        public void setState​(SolrCache.State state)
        Description copied from interface: SolrCache
        Set different cache states. The state a cache is in can have an effect on how statistics are kept. The cache user (SolrIndexSearcher) will take care of switching cache states.
        Specified by:
        setState in interface SolrCache<K,​V>
      • warm

        public void warm​(SolrIndexSearcher searcher,
                         SolrCache old)
        Description copied from interface: SolrCache
        Warm this cache associated with searcher using the old cache object. this and old will have the same concrete type.
        Specified by:
        warm in interface SolrCache<K,​V>
      • close

        public void close()
        Description copied from interface: SolrCache
        Frees any non-memory resources
        Specified by:
        close in interface SolrCache<K,​V>
      • getName

        public String getName()
        Description copied from interface: SolrInfoBean
        Simple common usage name, e.g. BasicQueryHandler, or fully qualified class name.
        Specified by:
        getName in interface SolrInfoBean
      • getMetricNames

        public Set<String> getMetricNames()
        Description copied from interface: SolrInfoBean
        Modifiable set of metric names that this component reports (default is null, which means none). If not null then this set is used by SolrInfoBean.registerMetricName(String) to capture what metrics names are reported from this component.

        NOTE: this set has to allow iteration under modifications.

        Specified by:
        getMetricNames in interface SolrInfoBean
      • getMetricRegistry

        public com.codahale.metrics.MetricRegistry getMetricRegistry()
        Description copied from interface: SolrInfoBean
        An instance of MetricRegistry that this component uses for metrics reporting (default is null, which means no registry).
        Specified by:
        getMetricRegistry in interface SolrInfoBean