Object
The Tuplespace manages access to the tuples it contains, ensuring mutual exclusion requirements are met.
The sec
option for the write, take, move, read and notify
methods may either be a number of seconds or a Renewer object.
Creates a new TupleSpace.
period
is used to control how often to look for dead tuples
after modifications to the TupleSpace.
If no dead tuples are found period
seconds after the last
modification, the TupleSpace will stop
looking for dead tuples.
# File rinda/tuplespace.rb, line 437 def initialize(period=60) super() @bag = TupleBag.new @read_waiter = TupleBag.new @take_waiter = TupleBag.new @notify_waiter = TupleBag.new @period = period @keeper = nil end
Moves tuple
to port
.
# File rinda/tuplespace.rb, line 484 def move(port, tuple, sec=nil) template = WaitTemplateEntry.new(self, tuple, sec) yield(template) if block_given? synchronize do entry = @bag.find(template) if entry port.push(entry.value) if port @bag.delete(entry) notify_event('take', entry.value) return port ? nil : entry.value end raise RequestExpiredError if template.expired? begin @take_waiter.push(template) start_keeper if template.expires while true raise RequestCanceledError if template.canceled? raise RequestExpiredError if template.expired? entry = @bag.find(template) if entry port.push(entry.value) if port @bag.delete(entry) notify_event('take', entry.value) return port ? nil : entry.value end template.wait end ensure @take_waiter.delete(template) end end end
Registers for notifications of event
. Returns a NotifyTemplateEntry. See NotifyTemplateEntry for examples of how
to listen for notifications.
event
can be:
A tuple was added
A tuple was taken or moved
A tuple was lost after being overwritten or expiring
The TupleSpace will also notify you of the ‘close’ event when the NotifyTemplateEntry has expired.
# File rinda/tuplespace.rb, line 567 def notify(event, tuple, sec=nil) template = NotifyTemplateEntry.new(self, event, tuple, sec) synchronize do @notify_waiter.push(template) end template end
Reads tuple
, but does not remove it.
# File rinda/tuplespace.rb, line 521 def read(tuple, sec=nil) template = WaitTemplateEntry.new(self, tuple, sec) yield(template) if block_given? synchronize do entry = @bag.find(template) return entry.value if entry raise RequestExpiredError if template.expired? begin @read_waiter.push(template) start_keeper if template.expires template.wait raise RequestCanceledError if template.canceled? raise RequestExpiredError if template.expired? return template.found ensure @read_waiter.delete(template) end end end
Returns all tuples matching tuple
. Does not remove the found
tuples.
# File rinda/tuplespace.rb, line 545 def read_all(tuple) template = WaitTemplateEntry.new(self, tuple, nil) synchronize do entry = @bag.find_all(template) entry.collect do |e| e.value end end end
Removes tuple
# File rinda/tuplespace.rb, line 477 def take(tuple, sec=nil, &block) move(nil, tuple, sec, &block) end
Adds tuple
# File rinda/tuplespace.rb, line 450 def write(tuple, sec=nil) entry = create_entry(tuple, sec) synchronize do if entry.expired? @read_waiter.find_all_template(entry).each do |template| template.read(tuple) end notify_event('write', entry.value) notify_event('delete', entry.value) else @bag.push(entry) start_keeper if entry.expires @read_waiter.find_all_template(entry).each do |template| template.read(tuple) end @take_waiter.find_all_template(entry).each do |template| template.signal end notify_event('write', entry.value) end end entry end