can we assign an Exception Class object to the reference of Object class object

Question

why this is will not work, can any one give the exact answer for this one....

public class Manager
{
     public static void main(String args[])
     {
         try{

                 Object obj=new A();   //it will generate ClassNotFoundException object
                 System.out.println("currently the reference obj is pointer to the object:"+obj);

            }catch(Object o)
                  {
                      System.out.println(o);
                  }

        }

     System.out.println("End of Main");
}       

Answer 1

That won't work simply because the variable declared in the "catch" statement has to be an exception type (i.e. Throwable or a subtype).

From section 14.20 of the Java Language Specification:

A catch clause must have exactly one parameter (which is called an exception parameter); the declared type of the exception parameter must be the class Throwable or a subclass (not just a subtype) of Throwable, or a compile-time error occurs.In particular, it is a compile-time error if the declared type of the exception parameter is a type variable (§4.4). The scope of the parameter variable is the Block of the catch clause.

Of course you could write:

catch(Throwable t)
{
    Object o = t;
    System.out.println(o);
}

It's not clear why you'd want to though.

Answer 2

You said nothing about class A's constructor... Is it actually throwing an exception ? If yes, then the other answers should help you out. If no, then perhaps I might recall that instanciating an exception is not throwing an exception...

Examples :

This won't work :

try {
 new Exception();
} catch (Exception e) {
 System.out.println("This will never be printed...");
}

However you can get the intended result by adding the throw keyword :

try {
 throw new Exception();
} catch (Exception e) {
 System.out.println("This will actually be printed...");
}