Package org.apache.hc.client5.http.impl.cache

Class CacheValidityPolicy

  • class CacheValidityPolicy
extends java.lang.Object

    • Field Detail

      • LOG

        private static final org.slf4j.Logger LOG

      • shared

        private final boolean shared

      • useHeuristicCaching

        private final boolean useHeuristicCaching

      • heuristicCoefficient

        private final float heuristicCoefficient

      • heuristicDefaultLifetime

        private final org.apache.hc.core5.util.TimeValue heuristicDefaultLifetime

    • Constructor Detail

      • CacheValidityPolicy

        CacheValidityPolicy​(CacheConfig config)
        Constructs a CacheValidityPolicy with the provided CacheConfig. If the config is null, it will use default heuristic coefficient and default heuristic lifetime from CacheConfig.DEFAULT.
        Parameters:
        config - The CacheConfig to use for this CacheValidityPolicy. If null, default values are used.

      • CacheValidityPolicy

        CacheValidityPolicy()
        Default constructor for CacheValidityPolicy. Initializes the policy with default values.

    • Method Detail

      • getCurrentAge

        public org.apache.hc.core5.util.TimeValue getCurrentAge​(HttpCacheEntry entry,
                                                        java.time.Instant now)

      • getFreshnessLifetime

        public org.apache.hc.core5.util.TimeValue getFreshnessLifetime​(ResponseCacheControl responseCacheControl,
                                                               HttpCacheEntry entry)
        Calculate the freshness lifetime of a response based on the provided cache control and cache entry.
        • If the cache is shared and the s-maxage response directive is present, use its value.
        • If the max-age response directive is present, use its value.
        • If the Expires response header field is present, use its value minus the value of the Date response header field.
        • Otherwise, a heuristic freshness lifetime might be applicable.
        Parameters:
        responseCacheControl - the cache control directives associated with the response.
        entry - the cache entry associated with the response.
        Returns:
        the calculated freshness lifetime as a TimeValue.

      • getHeuristicFreshnessLifetime

        org.apache.hc.core5.util.TimeValue getHeuristicFreshnessLifetime​(HttpCacheEntry entry)

      • getApparentAge

        org.apache.hc.core5.util.TimeValue getApparentAge​(HttpCacheEntry entry)

      • getAgeValue

        long getAgeValue​(HttpCacheEntry entry)
        Extracts and processes the Age value from an HttpCacheEntry by tokenizing the Age header value. The Age header value is interpreted as a sequence of tokens, and the first token is parsed into a number representing the age in delta-seconds. If the first token cannot be parsed into a number, the Age value is considered as invalid and this method returns 0. If the first token represents a negative number or a number that exceeds Integer.MAX_VALUE, the Age value is set to MAX_AGE (in seconds). This method uses CacheSupport.parseTokens to robustly handle the Age header value.

        Note: If the HttpCacheEntry contains multiple Age headers, only the first one is considered.

        Parameters:
        entry - The HttpCacheEntry from which to extract the Age value.
        Returns:
        The Age value in delta-seconds, or MAX_AGE in seconds if the Age value exceeds Integer.MAX_VALUE or is negative. If the Age value is invalid (cannot be parsed into a number or contains non-numeric characters), this method returns 0.

      • getCorrectedAgeValue

        org.apache.hc.core5.util.TimeValue getCorrectedAgeValue​(HttpCacheEntry entry)

      • getResponseDelay

        org.apache.hc.core5.util.TimeValue getResponseDelay​(HttpCacheEntry entry)

      • getCorrectedInitialAge

        org.apache.hc.core5.util.TimeValue getCorrectedInitialAge​(HttpCacheEntry entry)

      • getResidentTime

        org.apache.hc.core5.util.TimeValue getResidentTime​(HttpCacheEntry entry,
                                                   java.time.Instant now)