Parent

Files

Class/Module Index [+]

Quicksearch

Concurrent::Map

`Concurrent::Map` is a hash-like object and should have much better performance characteristics, especially under high concurrency, than `Concurrent::Hash`. However, `Concurrent::Map `is not strictly semantically equivalent to a ruby `Hash` -- for instance, it does not necessarily retain ordering by insertion time as `Hash` does. For most uses it should do fine though, and we recommend you consider `Concurrent::Map` instead of `Concurrent::Hash` for your concurrency-safe hash needs.

> require 'concurrent' > > map = Concurrent::Map.new

Public Class Methods

new(options = nil, &block) click to toggle source
# File lib/concurrent/map.rb, line 43
def initialize(options = nil, &block)
  if options.kind_of?(::Hash)
    validate_options_hash!(options)
  else
    options = nil
  end

  super(options)
  @default_proc = block
end

Public Instance Methods

[](key) click to toggle source
# File lib/concurrent/map.rb, line 54
def [](key)
  if value = super # non-falsy value is an existing mapping, return it right away
    value
    # re-check is done with get_or_default(key, NULL) instead of a simple !key?(key) in order to avoid a race condition, whereby by the time the current thread gets to the key?(key) call
    # a key => value mapping might have already been created by a different thread (key?(key) would then return true, this elsif branch wouldn't be taken and an incorrent +nil+ value
    # would be returned)
    # note: nil == value check is not technically necessary
  elsif @default_proc && nil == value && NULL == (value = get_or_default(key, NULL))
    @default_proc.call(self, key)
  else
    value
  end
end
Also aliased as: get
each_key() click to toggle source
# File lib/concurrent/map.rb, line 117
def each_key
  each_pair {|k, v| yield k}
end
each_value() click to toggle source
# File lib/concurrent/map.rb, line 121
def each_value
  each_pair {|k, v| yield v}
end
empty?() click to toggle source
# File lib/concurrent/map.rb, line 131
def empty?
  each_pair {|k, v| return false}
  true
end
fetch(key, default_value = NULL) click to toggle source
# File lib/concurrent/map.rb, line 71
def fetch(key, default_value = NULL)
  if NULL != (value = get_or_default(key, NULL))
    value
  elsif block_given?
    yield key
  elsif NULL != default_value
    default_value
  else
    raise_fetch_no_key
  end
end
fetch_or_store(key, default_value = NULL) click to toggle source
# File lib/concurrent/map.rb, line 83
def fetch_or_store(key, default_value = NULL)
  fetch(key) do
    put(key, block_given? ? yield(key) : (NULL == default_value ? raise_fetch_no_key : default_value))
  end
end
get(key) click to toggle source
Alias for: []
index(value) click to toggle source
Alias for: key
key(value) click to toggle source
# File lib/concurrent/map.rb, line 125
def key(value)
  each_pair {|k, v| return k if v == value}
  nil
end
Also aliased as: index
keys() click to toggle source
# File lib/concurrent/map.rb, line 105
def keys
  arr = []
  each_pair {|k, v| arr << k}
  arr
end
marshal_dump() click to toggle source
# File lib/concurrent/map.rb, line 142
def marshal_dump
  raise TypeError, "can't dump hash with default proc" if @default_proc
  h = {}
  each_pair {|k, v| h[k] = v}
  h
end
marshal_load(hash) click to toggle source
# File lib/concurrent/map.rb, line 149
def marshal_load(hash)
  initialize
  populate_from(hash)
end
put_if_absent(key, value) click to toggle source
# File lib/concurrent/map.rb, line 89
def put_if_absent(key, value)
  computed = false
  result = compute_if_absent(key) do
    computed = true
    value
  end
  computed ? nil : result
end
size() click to toggle source
# File lib/concurrent/map.rb, line 136
def size
  count = 0
  each_pair {|k, v| count += 1}
  count
end
value?(value) click to toggle source
# File lib/concurrent/map.rb, line 98
def value?(value)
  each_value do |v|
    return true if value.equal?(v)
  end
  false
end
values() click to toggle source
# File lib/concurrent/map.rb, line 111
def values
  arr = []
  each_pair {|k, v| arr << v}
  arr
end

[Validate]

Generated with the Darkfish Rdoc Generator 2.