Re: Statements before super()

From:

Tom Anderson <twic@urchin.earth.li>

Newsgroups:

comp.lang.java.programmer

Date:

Wed, 10 Feb 2010 23:07:07 +0000

Message-ID:

<alpine.DEB.1.10.1002102305450.21102@urchin.earth.li>

On Wed, 10 Feb 2010, Lew wrote:

Mike Schilling wrote:

Tom Anderson wrote:

On Wed, 10 Feb 2010, Mike Schilling wrote:

Tom Anderson wrote:

new SeparatedString("foo=bar", '=')

is equivalent to:

new StringPair("foo", "bar)
*/
class SeparatedString {
public SeparatedString(String str, char separator) {
// now what?

   this(split(str, separator));
   }
}
private String[] split(String str, char separator)
{
   ...
}

private SeparatedString(String[] strings)
{
   super(strings[0], strings[1]);
}

I refuse to be concerned about the cost of the allocation of the
String array.

Okay. So now:

/** A string pair combining a search term, and the string resulting
from using the term as the parameter to the supplied query.
*/
class TermAndResult extends StringPair {
public KeyAndValueString(String term, PreparedStatement query) {
// and no, it's not Derby or H2
}
}

Believe me, i can keep contriving examples all week!

The same thing, but make "split" talk to the DBMS, and probably thow some
interesting exceptions.

Ugh, you're right. Sorry, not thinking terribly clearly there.

Believe us, all those examples you contrive can be handled with existing
Java semantics. Since by definition what you put in there cannot rely
on the instance being constructed, it must be available through a static
method call.

I'm not claming it can't be done. My point is that this pointless rule
forces ugly and in some cases actually inefficient workarounds. The
problem is the rule. The solution is to change it.

tom

--
Big Bang. No god. Fadeout. End. -- Stephen Baxter