The caching that in ObjectName most likely makes it faster, but for
your test, you should try a name with like 5 key value pairs, because
the JSR 77 names tend to be very long.
-dain
On Wednesday, September 3, 2003, at 03:34 AM, gianny DAMOUR wrote:
Simon wrote:
> My guess it it is faster to use a (pre-compiled) regular
> expression to
> grab the chunk you are interested in out our the string
> directly. Last
> I checked constructing an ObjectName was very expensive.
[...]
So, IMHO no need to use regexp.
I have done a micro-bench and the regexp approach is an order of
magnitude (2 times) slower than a naive ObjectName.getKeyProperty.
I used the RE of the JDK1.4, yet perhaps that Jakarta regexp is
quicker.
A snippet to check it for yourself:
Pattern pattern = Pattern.compile("(.*):j2eeType=(.*)");
int iter = 100000;
long start = System.currentTimeMillis();
for (int i = 0; i < iter; i++) {
Matcher m = pattern.matcher("fwewe:j2eeType=ffqwefqwe");
m.matches();
m.group(2);
}
long end = System.currentTimeMillis();
System.out.println("perf=" + (end - start));
start = System.currentTimeMillis();
for (int i = 0; i < iter; i++) {
ObjectName name = new
ObjectName("fwewe:j2eeType=ffqwefqwe");
name.getKeyProperty("j2eeType");
}
end = System.currentTimeMillis();
System.out.println("perf=" + (end - start));
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