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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.
Removes all objects from the queue.
 
               # File thread.rb, line 324
def clear
  super
  @mutex.synchronize do
    @max.times do
      @enque_cond.signal
    end
  end
end
             
            Returns the maximum size of the queue.
 
               # File thread.rb, line 274
def max
  @max
end
             
            Sets the maximum size of the queue.
 
               # File thread.rb, line 281
def max=(max)
  raise ArgumentError, "queue size must be positive" unless max > 0
  @mutex.synchronize do
    if max <= @max
      @max = max
    else
      diff = max - @max
      @max = max
      diff.times do
        @enque_cond.signal
      end
    end
  end
  max
end
             
            Returns the number of threads waiting on the queue.
 
               # File thread.rb, line 369
def num_waiting
  @num_waiting + @num_enqueue_waiting
end
             
            Retrieves data from the queue and runs a waiting thread, if any.
 
               # File thread.rb, line 346
def pop(*args)
  retval = super
  @mutex.synchronize do
    if @que.length < @max
      @enque_cond.signal
    end
  end
  retval
end
             
            Pushes obj to the queue.  If there is no space left in the
queue, waits until space becomes available.
 
               # File thread.rb, line 302
def push(obj)
  Thread.handle_interrupt(RuntimeError => :on_blocking) do
    @mutex.synchronize do
      while true
        break if @que.length < @max
        @num_enqueue_waiting += 1
        begin
          @enque_cond.wait @mutex
        ensure
          @num_enqueue_waiting -= 1
        end
      end
      @que.push obj
      @cond.signal
    end
  end
end