String interning (WAS: SAX2/Java: Towards a final form)

[Miles Sabin]

Tyler Baker wrote,
> For most documents, making a call to String.intern()
> 50-100 times in a 100KB document is a lot less expensive than 
> doing:
>
> if (x.equals("foo") {
> 
> }
> else if (x.equals("bar") {
>
> }
> etc...
> 
> As opposed to:
>
> if (x == "foo") {
> 
> }
> else if (x == "bar) {
>
>}
> etc.
>
> Calling the equals method can get expensive for large case > > statements.

Sure ... so Don't Do That (tm) ...

If you've got what's effectively a huge case statement then
use a lookup table ... a HashMap or a trie of some sort or
another. Either of those will outperform a large number of
chained String.equals() calls or == tests.

Cheers,


Miles

-- 
Miles Sabin                       Cromwell Media
Internet Systems Architect        5/6 Glenthorne Mews
+44 (0)20 8817 4030               London, W6 0LJ, England
msabin at cromwellmedia.com          http://www.cromwellmedia.com/


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