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authormatz <matz@b2dd03c8-39d4-4d8f-98ff-823fe69b080e>2001-11-28 14:56:32 +0000
committermatz <matz@b2dd03c8-39d4-4d8f-98ff-823fe69b080e>2001-11-28 14:56:32 +0000
commit6ab0ff977d84d816cefa7a92c15aacd5b6694087 (patch)
tree645af2c635e9d5835c04e9136b163940ae4ef0c1 /lib/singleton.rb
parent186c8b592a8b5badfd42ff7295c5edb44ef1abdd (diff)
* eval.c (rb_thread_select): should subtract timeofday() from
limit, not reverse. * util.c (scan_hex): x is not a hexadecimal digit. * eval.c (rb_thread_schedule): should treat the case that select(2) returns 0, if a thread is under both WAIT_SELECT and WAIT_TIME. Jakub Travnik <J.Travnik@sh.cvut.cz> actually fixed this bug. git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@1862 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
Diffstat (limited to 'lib/singleton.rb')
-rw-r--r--lib/singleton.rb90
1 files changed, 49 insertions, 41 deletions
diff --git a/lib/singleton.rb b/lib/singleton.rb
index 696d37c..3ab048f 100644
--- a/lib/singleton.rb
+++ b/lib/singleton.rb
@@ -25,8 +25,8 @@
#
#
# This achieved by marking
-# * Klass.new and Klass.allocate - as private and
-# * Klass.inherited(sub_klass) - modifying to ensure
+# * Klass.new and Klass.allocate - as private and modifying
+# * Klass.inherited(sub_klass) - to ensure
# that the Singleton pattern is properly inherited.
#
# In addition Klass is provided with the class methods
@@ -39,7 +39,7 @@
# The sole instance method of Singleton is
# * _dump(depth) - returning the empty string
# The default Marshalling strategy is to strip all state information - i.e.
-# instance variables from ``the instance''. Providing costume
+# instance variables from ``the instance''. Providing custom
# _dump(depth) and _load(str) method allows the (partial) resurrection
# of a previous state of ``the instance'' - see third example.
#
@@ -53,12 +53,12 @@ module Singleton
# * nil - before (and after a failed) creation
# * false - during creation
# * sub_class instance - after a successful creation
- @__instance__ = nil
+ sub_klass.instance_eval { @__instance__ = nil }
def sub_klass.instance
unless @__instance__.nil?
# is the extra flexiblity having the hook method
# _wait() around ever useful?
- _wait() while false.equal?(@__instance__)
+ _wait()
# check for instance creation
return @__instance__ if @__instance__
end
@@ -86,7 +86,7 @@ module Singleton
instance
end
def _wait
- sleep(0.05)
+ sleep(0.05) while false.equal?(@__instance__)
end
private :new, :allocate
# hook methods are also marked private
@@ -115,55 +115,63 @@ rescue NoMethodError => mes
puts mes
end
-# threaded example with exception
-Thread.abort_on_exception = true
-class Ups < SomeSingletonClass
- @__threads__= []
- @__flip__ = nil
- @@__index__ = nil
+# threaded example with exception and customized hook #_wait method
+Thread.abort_on_exception = false
+def num_of_instances(mod)
+ "#{ObjectSpace.each_object(mod){}} #{mod} instance"
+end
+class Ups < SomeSingletonClass
def initialize
- sleep(rand(0.1)/10.0)
- Thread.current[:index] = @@__index__
+ type.__sleep
+ puts "initialize called by thread ##{Thread.current[:i]}"
end
class << self
+ def _wait
+ @enter.push Thread.current[:i]
+ sleep 0.02 while false.equal?(@__instance__)
+ @leave.push Thread.current[:i]
+ end
+ def __sleep
+ sleep (rand(0.1))
+ end
def allocate
- unless @__flip__
- @__flip__ = true
- raise "boom - allocation in thread ##{@@__index__} aborted"
- end
- super()
+ __sleep
+ def self.allocate; __sleep; super() end
+ raise "allocation in thread ##{Thread.current[:i]} aborted"
end
def instanciate_all
- 1.upto(5) do |@@__index__|
- sleep(rand(0.1)/10.0)
- @__threads__.push Thread.new {
- begin
- instance
- rescue RuntimeError => mes
- puts mes
- end
- }
+ @enter = []
+ @leave = []
+ 1.upto(9) do |i|
+ Thread.new do
+ begin
+ Thread.current[:i] = i
+ __sleep
+ instance
+ rescue RuntimeError => mes
+ puts mes
+ end
end
end
- def join
- @__threads__.each do |t|
- t.join
- puts "initialize called by thread ##{t[:index]}" if
-t[:index]
- end
+ puts "Before there were #{num_of_instances(Ups)}s"
+ sleep 3
+ puts "Now there is #{num_of_instances(Ups)}"
+ puts "#{@enter.join "; "} was the order of threads entering the waiting loop"
+ puts "#{@leave.join "; "} was the order of threads leaving the waiting loop"
end
end
end
-
-puts "There is(are) #{ObjectSpace.each_object(Ups) {}} Ups instance(s)"
- # => The is(are) 0 Ups instance(s)
Ups.instanciate_all
-Ups.join # => initialize called by thread # i - where i = 2 ... 5
-p Marshal.load(Marshal.dump(Ups.instance)) == Ups.instance # => true
-puts "There is(are) #{ObjectSpace.each_object(Ups) {}} Ups instance(s)"
- # => The is(are) 1 Ups instance(s)
+# results in message like
+# Before there were 0 Ups instances
+# boom - allocation in thread #8 aborted
+# initialize called by thread #3
+# Now there is 1 Ups instance
+# 2; 3; 6; 1; 7; 5; 9; 4 was the order of threads entering the waiting loop
+# 3; 2; 1; 7; 6; 5; 4; 9 was the order of threads leaving the waiting loop
+
# Customized marshalling
class A