From: Dave Mihalik <dmihalik@...>
Date: 2006-07-28T04:21:06+09:00
Subject: Prevent class instantiation from the initialize method?


Can some show me how to implement this java program using Ruby?
I am simply trying to prevent the testclass from being instantiated in 
the constructor.
I am then checking to see if the the class has instanatiated properly.

class testclass
{
public testclass() throws Exception
{

   Exception testexception;
   testexception = new Exception("Instantiation cancelled.");
   throw testexception;

}}

public class testprogram
{
public static void main(final String taArgv[])
{
   testclass mytest = null;

   try
   {
      mytest = new testclass();
   }
   catch(Exception myexception)
   {
      System.out.println(myexception.getMessage());
   }

   if (mytest == null)
   {
      System.exit(1);

   }
   System.out.println("Instantiation not cancelled.");
}}


I am new to Ruby but this is what I have so far:

class Testclass
  def initialize()

    raise "Instantiation cancelled."

  end
end

begin

   mytest = Testclass.new()

   rescue Exception => e
   begin

      puts e
      exit 1

   end

   puts "Instantiation not cancelled."


end

If the raise line in the initialize method is disabled, the puts 
"Instantiation not cancelled." line does not execute.

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