Object
A TupleEntry is a Tuple (i.e. a possible entry in some Tuplespace) together with expiry and cancellation data.
Creates a TupleEntry based on
ary with an optional renewer or expiry time sec.
A renewer must implement the renew method which returns a
Numeric, nil, or true to indicate when the tuple has expired.
# File rinda/tuplespace.rb, line 25
def initialize(ary, sec=nil)
@cancel = false
@expires = nil
@tuple = make_tuple(ary)
@renewer = nil
renew(sec)
end
Retrieves key from the tuple.
# File rinda/tuplespace.rb, line 109
def [](key)
@tuple[key]
end
A TupleEntry is dead when it is canceled or expired.
# File rinda/tuplespace.rb, line 43
def alive?
!canceled? && !expired?
end
Marks this TupleEntry as canceled.
# File rinda/tuplespace.rb, line 36
def cancel
@cancel = true
end
Returns the canceled status.
# File rinda/tuplespace.rb, line 56
def canceled?; @cancel; end
Has this tuple expired? (true/false).
A tuple has expired when its expiry timer based on the sec
argument to initialize runs out.
# File rinda/tuplespace.rb, line 64
def expired?
return true unless @expires
return false if @expires > Time.now
return true if @renewer.nil?
renew(@renewer)
return true unless @expires
return @expires < Time.now
end
Fetches key from the tuple.
# File rinda/tuplespace.rb, line 116
def fetch(key)
@tuple.fetch(key)
end
Returns an expiry Time based on sec which can be one of:
sec seconds into the future
true
the expiry time is the start of 1970 (i.e. expired)
nil
it is Tue Jan 19 03:14:07 GMT Standard Time 2038 (i.e. when UNIX clocks will die)
# File rinda/tuplespace.rb, line 95
def make_expires(sec=nil)
case sec
when Numeric
Time.now + sec
when true
Time.at(1)
when nil
Time.at(2**31-1)
end
end
Creates a Rinda::Tuple for ary.
# File rinda/tuplespace.rb, line 130
def make_tuple(ary)
Rinda::Tuple.new(ary)
end
Reset the expiry time according to sec_or_renewer.
nil
it is set to expire in the far future.
true
it has expired.
it will expire in that many seconds.
Otherwise the argument refers to some kind of renewer object which will reset its expiry time.
# File rinda/tuplespace.rb, line 83
def renew(sec_or_renewer)
sec, @renewer = get_renewer(sec_or_renewer)
@expires = make_expires(sec)
end