Re: I lost the point: purpose of putting objects to null?

From: AnonymousOne (nobody_at_nowhere.org)
Date: 09/23/04 

Date: Thu, 23 Sep 2004 20:23:06 GMT

I personally use this to test if an object was ever set or not. If you
just check for (x == null) without actually SETTING x to null, then the
compiler would give you a "x may not be initialized" error.

Example:

java.sql.Connection c;

try {
        c = java.sql.DriverManager.connect(...);
        java.sql.Statement s = c.createStatement();
        ...
}
catch (Throwable thrown) {
        // some code here
}
finally {
        if (c == null) then c.close();
}

This example would not compile, because "c" is never initialized.
However, if we change the first line to:

java.sql.Connection c = null;

Then the finally block would work.

Dado wrote:
> I lost the point:
> What is purpose of putting objects to null:
>
> If I make a class, JFrame for example, with button which start connection
> dialog, which is class with connection and statement Object.
> And every time I click the button first I put :
> dialog = null
> dialog = new dialog()
>
> What is purpose to put dialog = null when all its objects are stay non-null?
>
>
>
>
>
> ---
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