Class ConcurrentLruCache<T>

java.lang.Object
org.apache.tomcat.util.collections.ConcurrentLruCache<T>
Type Parameters:
T - the type of entries stored in the cache
public class ConcurrentLruCache<T> extends Object
A thread-safe LRU (Least Recently Used) cache with a configurable size limit. Entries beyond the limit are evicted in LRU order.

  • Constructor Summary

    Constructors
    Constructor
    Description
    ConcurrentLruCache(int limit)
    Creates a new LRU cache with the specified size limit.

  • Method Summary

    Modifier and Type
    Method
    Description
    void
    add(T entry)
    Adds an entry to the cache.
    void
    clear()
    Removes all entries from the cache.
    boolean
    contains(T entry)
    Checks whether the cache contains the given entry.
    int
    getLimit()
    Returns the current maximum number of entries allowed in the cache.
    void
    setLimit(int limit)
    Sets the maximum number of entries in the cache.

    Methods inherited from class Object

    clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

  • Constructor Details

    • ConcurrentLruCache

      public ConcurrentLruCache(int limit)
      Creates a new LRU cache with the specified size limit.
      Parameters:
      limit - the maximum number of entries in the cache

  • Method Details

    • add

      public void add(T entry)
      Adds an entry to the cache. If the cache is at its limit, the least recently used entry will be evicted.
      Parameters:
      entry - the entry to add

    • contains

      public boolean contains(T entry)
      Checks whether the cache contains the given entry. Accessing an entry through this method updates its recency.
      Parameters:
      entry - the entry to check
      Returns:
      true if the entry is in the cache

    • clear

      public void clear()
      Removes all entries from the cache.

    • setLimit

      public void setLimit(int limit)
      Sets the maximum number of entries in the cache. If the new limit is smaller than the current size, the least recently used entries will be evicted. A limit of 0 or less disables the cache.
      Parameters:
      limit - the new maximum number of entries

    • getLimit

      public int getLimit()
      Returns the current maximum number of entries allowed in the cache.
      Returns:
      the cache limit, or -1 if the cache is disabled