RFR: 8058230: Improve java.sql toString formatting

[Lance Andersen]

Hi Claes,

I think this is OK,  however, would like to see if others feel if  formatDecimalInt should be located elsewhere so that we just make this change once.

Best,
Lance
On Sep 11, 2014, at 10:44 AM, Claes Redestad <claes.redestad at oracle.com> wrote:

> Hi,
> 
> requesting reviews for this patch which optimizes java.sql.Date/Time/Timestamp::toString
> by avoiding some unnecessary object allocations. java.sql.Date had similar optimizations
> applied which this patch improves upon.
> 
> bug: https://bugs.openjdk.java.net/browse/JDK-8058230
> webrev: http://cr.openjdk.java.net/~redestad/8058230/webrev.00/
> 
> Testing: jtreg jdk/test/java/sql with and without 8057826 tests
> 
> Before/after performance running a minimal JMH micro[1]:
> 
> Benchmark                         Mode  Samples      Score Score error   Units
> t.DateBench.dateToString         thrpt       20 30225.628      623.887  ops/ms
> t.DateBench.dateToString         thrpt       20 38350.173     1349.432  ops/ms  # 1.3x
> 
> t.DateBench.timeToString         thrpt       20 11793.338      232.121  ops/ms
> t.DateBench.timeToString         thrpt       20 47048.344     1969.939  ops/ms  # 4.0x
> 
> t.DateBench.timestampToString    thrpt       20 2529.601       45.990  ops/ms
> t.DateBench.timestampToString    thrpt       20 14143.612      407.351  ops/ms  # 5.6x
> 
> /Claes
> 
> [1]
> 
> package test;
> 
> import org.openjdk.jmh.annotations.*;
> 
> @State(Scope.Thread)
> public class DateBench {
> 
>    public java.sql.Time time = java.sql.Time.valueOf("15:15:25");
> 
>    @Benchmark
>    public String timeToString() {
>        return time.toString();
>    }
> 
>    public java.sql.Date date = java.sql.Date.valueOf("2013-01-01");
> 
>    @Benchmark
>    public String dateToString() {
>        return date.toString();
>    }
> 
>    public Timestamp timestamp = Timestamp.valueOf("1999-12-13 15:15:25.645634");
> 
>    @Benchmark
>    public String timestampToString() {
>        return timestamp.toString();
>    }
> 
> }



Lance Andersen| Principal Member of Technical Staff | +1.781.442.2037
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