RFR: JDK-8005263: Logging APIs takes Supplier<String> for message

Peter Levart peter.levart at gmail.com
Fri Dec 21 17:52:48 UTC 2012

Hi Henry, again,

To delay constructing message to as late as possible, you could 
construct a LogRecord with a reference to Supplier<String> and only 
evaluate the Supplier on the first call to LogRecord.getMessage() and 
then cache-it. Like the following:


Also, the "staging" Block call-back in doLog() is a very nice lambda 
usage, but it comes with a cost of constructing another lambda object 
for each call to those methods...

Regards, Peter

On 12/21/2012 07:28 AM, Henry Jen wrote:
> Hi,
> This patch adds a couple APIs to java.util.logging.Logger so that
> construction of log messages only occurs when it is actually to be
> logged by using Supplier<String> instead of String.
> Since the idea is to avoid unnecessary construction of log messages,
> thus APIs imply formatting are not provided. Thus all forms of logrb and
> log with Parameters are not included.
> log with Throwable are named to be logEx or logpEx to avoid null
> ambiguous as it seems like it's quite common usage with
> logger.log(level, null, thrown)
> Specdiff and webrev can be found at following,
> http://cr.openjdk.java.net/~henryjen/ccc/8005263.0/specdiff/diff.html
> http://cr.openjdk.java.net/~henryjen/ccc/8005263.0/webrev/
> Cheers,
> Henry

More information about the core-libs-dev mailing list