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Two exceptions

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I am writing something like a recursive descent parser: That is, I inspect 
object and its parts. When a part of an object is wrong, my method parse() 
throws my exception ParseException. It is sometimes handled in parse() of a 
higher-level object.

Example:

An object X may be either X1 or X2 or X3 class.

I try to call parse() for an object of X1 class. If it parses, the higher 
level parse() (for X) return X1 casted to X. If it fails with exception 
ParseException, X2 is tried, and if that fails too X3 is tried.

Or for an object X I try calling parse() for subobjects Y and Z. If either 
throws ParseException, the parse exception is propagated for parse() of X.

In this way, I consider an object and its possible parts. This is sometimes 
called recursive descent.

But I want also FatalParseException meant to stop parsing of a file 
altogether if it happens in the object or its subobject.

Human logic suggests that FatalParseException is a kind of ParseException 
and so should be its subclass. But this way handling ParseException we would 
also handle FatalParseException what is wrong, because FatalParseException 
is meant to be handled only in the outer method, outside of all parse() 
methods.

So I have two alternatives:

1. Derive ParseException from FatalParseException what seems to do the right 
thing but seems illogical.

2. Not derive either of these two exceptions from each other.

By the way, I am to rewrite an Ada project in Java (because the Ada compiler 
is too buggy and I can't work with it). In Ada all exceptions are 
independent (no exception is a subclass of another one).

-- 
Victor Porton - http://portonvictor.org

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Two exceptions Victor Porton <porton@narod.ru> - 2017-12-09 00:53 +0200
  Re: Two exceptions Eric Sosman <esosman@comcast-dot-net.invalid> - 2017-12-08 18:21 -0500
    Re: Two exceptions Victor Porton <porton@narod.ru> - 2017-12-09 01:55 +0200
      Re: Two exceptions Eric Sosman <esosman@comcast-dot-net.invalid> - 2017-12-09 07:39 -0500
        Re: Two exceptions Victor Porton <porton@narod.ru> - 2017-12-10 02:39 +0200
          Re: Two exceptions Victor Porton <porton@narod.ru> - 2017-12-10 02:46 +0200
          Re: Two exceptions Kiwi User <martin@mydomain.invalid> - 2017-12-10 00:52 +0000
      Re: Two exceptions Patrick Roemer <sangamon@netcologne.de> - 2017-12-09 13:47 +0100
  Re: Two exceptions Arne Vajhøj <arne@vajhoej.dk> - 2017-12-08 18:49 -0500
    Re: Two exceptions v_borchert@despammed.com (Volker Borchert) - 2017-12-09 07:53 +0000
  Re: Two exceptions Eric Sosman <esosman@comcast-dot-net.invalid> - 2017-12-09 14:55 -0500
    Re: Two exceptions Patrick Roemer <sangamon@netcologne.de> - 2017-12-11 15:09 +0100

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