Class: Copland::ServiceModel::Proxy

Inherits:
Object
  • Object
show all
Defined in:
lib/copland/models/proxy.rb

Overview

A proxy class to aid in deferred instantiation of service points. This is used primarily by the “deferred” service models.

Instance Method Summary collapse

Constructor Details

#initialize(service_point, &init) ⇒ Proxy

Create a new proxy that wraps the given service point.



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# File 'lib/copland/models/proxy.rb', line 44

def initialize( service_point, &init )
  @service_point = service_point
  @mutex = Mutex.new
  @init = init
end

Dynamic Method Handling

This class handles dynamic methods through the method_missing method

#method_missing(sym, *args, &block) ⇒ Object

Attempts to invoke the given message on the service. If the service has not yet been instantiated, it will be instantiated and stored.



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# File 'lib/copland/models/proxy.rb', line 52

def method_missing( sym, *args, &block )
  unless @instance || @instantiation_failed
    @mutex.synchronize do
      unless @instance || @instantiation_failed
        begin
          @instance = @service_point.instantiate( &@init )
        rescue Exception
          @instantiation_failed = true
          raise
        end
      end
    end
  end

  unless @instantiation_failed
    @instance.__send__ sym, *args, &block
  else
    # just return nil... this way, a failed instantiation won't barf
    # more than once... I hope...
  end
end

Instance Method Details

#inspect ⇒ Object 



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# File 'lib/copland/models/proxy.rb', line 91

def inspect
  "#<#{self.class.name}:#{"0x%08x"%self.id}:" +
  "service_point=>#{@service_point.full_name}:" +
  "instantiated=>#{@instance ? true : false}>"
end