shvets / design_patterns_in_ruby

# proxy.bsh
 
# Provides a surrogate or placeholder for another object to control access to it.
 
# 1. type interface
 
class Subject
  def process
  end
end
 
# 2. type implementation
 
class MySubject < Subject
  def process
    puts "my process"
  end
end
 
# 3.type proxy implementation
 
class SubjectProxy < Subject
 
  def initialize(subject)
    @subject = subject
  end
 
  def process
    @subject.process
  end
end
 
class DynamicSubjectProxy 
 
  def initialize(subject)
    @subject = subject
  end
 
#  def process
#    @subject.process
#  end
  def method_missing(name, *args)
    puts("Delegating #{name} message to subject.")
  
    @subject.send(name, *args)
  end
end
 
 
# 4. test 
 
proxy = SubjectProxy.new(MySubject.new)
 
proxy.process
 
dynamic_proxy = DynamicSubjectProxy.new(MySubject.new)
 
dynamic_proxy.process