Trait CacheAccessor 

pub trait CacheAccessor<K, V>: Send + Sync {
    // Required methods
    fn get(&self, key: &K) -> Option<V>;
    fn put(&self, key: &K, value: V) -> Option<V>;
    fn remove(&self, k: &K) -> Option<V>;
    fn contains_key(&self, k: &K) -> bool;
    fn len(&self) -> usize;
    fn clear(&self);
    fn name(&self) -> String;

    // Provided method
    fn is_empty(&self) -> bool { ... }
}

Base trait for cache implementations with common operations.

This trait provides the fundamental cache operations (get, put, remove, etc.) that all cache types share. Specific cache traits like cache_manager::FileStatisticsCache, cache_manager::ListFilesCache, and cache_manager::FileMetadataCache extend this trait with their specialized methods.

Thread Safety

Implementations must handle their own locking via internal mutability, as methods do not take mutable references and may be accessed by multiple concurrent queries.

Validation Pattern

Validation metadata (e.g., file size, last modified time) should be embedded in the value type V. The typical usage pattern is:

1. Call get(key) to check for cached value
2. If Some(cached), validate with cached.is_valid_for(&current_meta)
3. If invalid or missing, compute new value and call put(key, new_value)

Required Methods

fn get(&self, key: &K) -> Option<V>

Get a cached entry if it exists.

Returns the cached value without any validation. The caller should validate the returned value if freshness matters.

fn put(&self, key: &K, value: V) -> Option<V>

Store a value in the cache.

Returns the previous value if one existed.

fn remove(&self, k: &K) -> Option<V>

Remove an entry from the cache, returning the value if it existed.

fn contains_key(&self, k: &K) -> bool

Check if the cache contains a specific key.

fn len(&self) -> usize

Fetch the total number of cache entries.

fn clear(&self)

Remove all entries from the cache.

fn name(&self) -> String

Return the cache name.

Provided Methods

fn is_empty(&self) -> bool

Check if the cache collection is empty.

Implementors

impl CacheAccessor<Path, CachedFileMetadata> for DefaultFileStatisticsCache

impl CacheAccessor<Path, CachedFileMetadataEntry> for DefaultFilesMetadataCache

impl CacheAccessor<TableScopedPath, CachedFileList> for DefaultListFilesCache