Class: Foobara::LruCache

Inherits:
Object
  • Object
show all
Defined in:
foobara-lru-cache-0.0.2/lib/foobara/lru_cache.rb

Defined Under Namespace

Classes: Node

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(capacity = 10) ⇒ LruCache

Returns a new instance of LruCache.



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# File 'foobara-lru-cache-0.0.2/lib/foobara/lru_cache.rb', line 16

def initialize(capacity = 10)
  @capacity = capacity
  @size = 0
  @key_to_node = {}
  @head = @tail = nil
end

Instance Attribute Details

#size ⇒ Object (readonly)

Returns the value of attribute size.



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# File 'foobara-lru-cache-0.0.2/lib/foobara/lru_cache.rb', line 14

def size
  @size
end

Instance Method Details

#cached(key) ⇒ Object 



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# File 'foobara-lru-cache-0.0.2/lib/foobara/lru_cache.rb', line 23

def cached(key)
  mutex.synchronize do
    if @key_to_node.key?(key)
      node = @key_to_node[key]
      move_node_to_front(node)
      return node.value
    end
  end

  value = yield
  mutex.synchronize do
    if @key_to_node.key?(key)
      node = @key_to_node[key]
      move_node_to_front(node)
    else
      node = Node.new(key, value)
      @key_to_node[key] = node
      prepend_node(node)
    end
  end

  value
end

#key?(key) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'foobara-lru-cache-0.0.2/lib/foobara/lru_cache.rb', line 47

def key?(key)
  @key_to_node.key?(key)
end

#reset! ⇒ Object 



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# File 'foobara-lru-cache-0.0.2/lib/foobara/lru_cache.rb', line 51

def reset!
  mutex.synchronize do
    @size = 0
    @key_to_node.clear
    @head = @tail = nil
  end
end