In Files

  • thread.rb

Class/Module Index [+]

Quicksearch

SizedQueue

This class represents queues of specified size capacity. The push operation may be blocked if the capacity is full.

See Queue for an example of how a SizedQueue works.

Public Class Methods

new(max) click to toggle source

Creates a fixed-length queue with a maximum size of max.

 
               # File thread.rb, line 246
def initialize(max)
  raise ArgumentError, "queue size must be positive" unless max > 0
  @max = max
  @queue_wait = []
  @queue_wait.taint           # enable tainted comunication
  super()
end

Public Instance Methods

<<(obj) click to toggle source

Alias of push

Alias for: push
deq(*args) click to toggle source

Alias of pop

Alias for: pop
enq(obj) click to toggle source

Alias of push

Alias for: push
max() click to toggle source

Returns the maximum size of the queue.

 
               # File thread.rb, line 257
def max
  @max
end
max=(max) click to toggle source

Sets the maximum size of the queue.

 
               # File thread.rb, line 264
def max=(max)
  diff = nil
  @mutex.synchronize {
    if max <= @max
      @max = max
    else
      diff = max - @max
      @max = max
    end
  }
  if diff
    diff.times do
      begin
        t = @queue_wait.shift
        t.run if t
      rescue ThreadError
        retry
      end
    end
  end
  max
end
num_waiting() click to toggle source

Returns the number of threads waiting on the queue.

 
               # File thread.rb, line 361
def num_waiting
  @waiting.size + @queue_wait.size
end
pop(*args) click to toggle source

Retrieves data from the queue and runs a waiting thread, if any.

 
               # File thread.rb, line 328
def pop(*args)
  retval = super
  t = nil
  @mutex.synchronize {
    if @que.length < @max
      begin
        t = @queue_wait.shift
        t.wakeup if t
      rescue ThreadError
        retry
      end
    end
  }
  begin
    t.run if t
  rescue ThreadError
  end
  retval
end
Also aliased as: shift, deq
push(obj) click to toggle source

Pushes obj to the queue. If there is no space left in the queue, waits until space becomes available.

 
               # File thread.rb, line 291
def push(obj)
  t = nil
  @mutex.synchronize{
    while true
      break if @que.length < @max
      @queue_wait.push Thread.current
      @mutex.sleep
    end
  
    @que.push obj
    begin
      t = @waiting.shift
      t.wakeup if t
    rescue ThreadError
      retry
    end
  }
  
  begin
    t.run if t
  rescue ThreadError
  end
end
Also aliased as: <<, enq
shift(*args) click to toggle source

Alias of pop

Alias for: pop

Commenting is here to help enhance the documentation. For example, code samples, or clarification of the documentation.

If you have questions about Ruby or the documentation, please post to one of the Ruby mailing lists. You will get better, faster, help that way.

If you wish to post a correction of the docs, please do so, but also file bug report so that it can be corrected for the next release. Thank you.

If you want to help improve the Ruby documentation, please visit Documenting-ruby.org.

blog comments powered by Disqus