Benchmark.java

import java.math.BigDecimal;
import java.time.format.DateTimeFormatter;
import java.time.ZoneId;
import java.time.Instant;


public abstract class Benchmark {

    final String name;
    DateTimeFormatter format = DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss").
        withZone(ZoneId.of("Asia/Tokyo"));

    public Benchmark(String name) {
        this.name = name;
    }

    abstract long run(int iterations) throws Throwable;

    private BigDecimal time() {
        try {
            int nextI = 1;
            int i;
            long duration;
            do {
                i = nextI;
                long start = System.nanoTime();
                run(i);
                duration = System.nanoTime() - start;
                nextI = (i << 1) | 1;
            } while (duration < 100000000 && nextI > 0);
            return new BigDecimal((duration) * 1000 / i).movePointLeft(3);
        } catch (Throwable e) {
            throw new RuntimeException(e);
        }
    }

    @Override
    public String toString() {
        return name + "\t" + time() + " ns";
    }

    public static void main(String[] args) throws Exception {
        Benchmark[] benchmarks = {
            new Benchmark("try") {
                @Override long run(int iterations) throws Throwable {
                    long x = 0;
                    for (int i = 0; i < iterations; i++) {
                        try {
                            x += Instant.from(format.parse("2015-12-30 17:57:03")).toEpochMilli();
                        } catch (Exception e) {
                            e.printStackTrace();
                        }
                    }
                    return x;
                }
            }, new Benchmark("no try") {
                @Override long run(int iterations) throws Throwable {
                    long x = 0;
                    for (int i = 0; i < iterations; i++) {
                        x += Instant.from(format.parse("2015-12-30 17:57:03")).toEpochMilli();
                    }
                    return x;
                }
            }
        };
        for (Benchmark bm : benchmarks) {
            System.out.println(bm);
        }
    }
}

gistfile1.txt

$ javac Benchmark.java
$ java Benchmark
try	4305.802 ns
no try	874.378 ns