Struct SyncLruCache

pub struct SyncLruCache<K, V> { /* private fields */ }

A wrapper around LruCache. This struct is thread safe, doesn’t return any references to any elements inside.

Implementations

impl<K, V> SyncLruCache<K, V>

where K: Hash + Eq, V: Clone,

pub fn new(cap: usize) -> Self

Creates a new LRU cache that holds at most cap items.

pub fn len(&self) -> usize

Returns the number of key-value pairs that are currently in the cache.

pub fn is_empty(&self) -> bool

Returns true if the cache is empty and false otherwise.

pub fn contains(&self, key: &K) -> bool

Returns true if the cache contains the key and false otherwise.

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

Pushes a key-value pair into the cache. If an entry with key k already exists in the cache or another cache entry is removed (due to the lru’s capacity), then it returns the old entry’s key-value pair. Otherwise, returns None.

pub fn get_or_put<F>(&self, key: K, f: F) -> V

where V: Clone, F: FnOnce(&K) -> V,

Return the value of they key in the cache otherwise computes the value and inserts it into the cache. If the key is already in the cache, they get moved to the head of the LRU list.

pub fn get_or_try_put<F, E>(&self, key: K, f: F) -> Result<V, E>

where V: Clone, F: FnOnce(&K) -> Result<V, E>,

Returns the value of they key in the cache if present, otherwise computes the value using the provided closure.

If the key is already in the cache, it gets moved to the head of the LRU list.

If the provided closure fails, the error is returned and the cache is not updated.

pub fn put(&self, key: K, value: V)

Puts a key-value pair into cache. If the key already exists in the cache, then it updates the key’s value.

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

Returns the value of the key in the cache or None if it is not present in the cache. Moves the key to the head of the LRU list if it exists.

pub fn lock(&self) -> MutexGuard<'_, LruCache<K, V>>

Returns the lock over underlying LRU cache.