API: Speed up Timestamps#toHumanString #12447
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String#format uses regexes internally which can be expensive when used repeatedly. This PR switches out the implementation for a simple char array implementation that pads zeros as needed. A simple benchmark was written to compare these 2 implementations which shows an improvement from ~ 300ns per op to 15ns per op ``` Benchmark (monthOrdinal) Mode Cnt Score Error Units DateFormattingBenchmark.charArrayFormat 0 avgt 10 17.580 ± 5.029 ns/op DateFormattingBenchmark.charArrayFormat 1 avgt 10 16.082 ± 0.220 ns/op DateFormattingBenchmark.charArrayFormat 12 avgt 10 13.504 ± 0.151 ns/op DateFormattingBenchmark.charArrayFormat 15 avgt 10 13.541 ± 0.684 ns/op DateFormattingBenchmark.charArrayFormat 123 avgt 10 17.616 ± 5.112 ns/op DateFormattingBenchmark.charArrayFormat 1234 avgt 10 13.350 ± 0.544 ns/op DateFormattingBenchmark.charArrayFormat 12345 avgt 10 13.656 ± 0.128 ns/op DateFormattingBenchmark.stringFormat 0 avgt 10 296.576 ± 1.027 ns/op DateFormattingBenchmark.stringFormat 1 avgt 10 356.724 ± 277.416 ns/op DateFormattingBenchmark.stringFormat 12 avgt 10 320.441 ± 1.802 ns/op DateFormattingBenchmark.stringFormat 15 avgt 10 298.042 ± 11.098 ns/op DateFormattingBenchmark.stringFormat 123 avgt 10 302.227 ± 11.005 ns/op DateFormattingBenchmark.stringFormat 1234 avgt 10 309.586 ± 11.386 ns/op DateFormattingBenchmark.stringFormat 12345 avgt 10 305.583 ± 1.682 ns/op ```
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String#format uses regexes internally which can be expensive when used repeatedly. This PR switches out the implementation for a char array implementation that pads zeros as needed.
A simple benchmark was written to compare these 2 implementations which shows an improvement from ~ 300ns per op to 15ns per op