Re2j runs 5x slower than java.util.regex

Here is my benchmark:

```java

import org.apache.commons.lang3.RandomStringUtils;
import org.openjdk.jmh.annotations.Benchmark;
import org.openjdk.jmh.annotations.BenchmarkMode;
import org.openjdk.jmh.annotations.Fork;
import org.openjdk.jmh.annotations.Measurement;
import org.openjdk.jmh.annotations.Mode;
import org.openjdk.jmh.annotations.OutputTimeUnit;
import org.openjdk.jmh.annotations.Scope;
import org.openjdk.jmh.annotations.Setup;
import org.openjdk.jmh.annotations.State;
import org.openjdk.jmh.annotations.Threads;
import org.openjdk.jmh.annotations.Warmup;

import java.util.Iterator;
import java.util.List;
import java.util.concurrent.TimeUnit;
import java.util.regex.Pattern;
import java.util.stream.Collectors;
import java.util.stream.IntStream;

@Warmup(iterations = 2, time = 3)
@Measurement(iterations = 2, time = 3)
@State(Scope.Thread)
@BenchmarkMode(Mode.AverageTime)
@OutputTimeUnit(TimeUnit.NANOSECONDS)
@Threads(3)
@Fork(1)
/*
*

 *     Benchmark                Mode  Cnt     Score   Error  Units

 * Re2jBenchmark.javaMatch  avgt    2   175.926          ns/op

 * Re2jBenchmark.re2jMatch  avgt    2  1067.591          ns/op

 *     
 */

public class Re2jBenchmark {


  private static final String PATTERN = "[0-5][0-6]{1,3}[1-7]{1,2}[2580]{1,3}[127]{0,8}";

  private static final Pattern p1 = Pattern.compile(PATTERN);

  private static final com.google.re2j.Pattern p2 = com.google.re2j.Pattern.compile(PATTERN);

  private List inputs;

  private Iterator iterator;

  @Setup

  public void setup() {

    inputs =

        IntStream.rangeClosed(0, 999)

            .mapToObj(n -> RandomStringUtils.randomNumeric(32))

            .collect(Collectors.toList());

    iterator = inputs.listIterator();

  }

  private String nextInput() {

    if (!iterator.hasNext()) {

      iterator = inputs.listIterator();

    }

    return iterator.next();

  }

  @Benchmark

  public boolean javaMatch() {

    return p1.matcher(nextInput()).find();

  }

  @Benchmark

  public boolean re2jMatch() {

    return p2.matcher(nextInput()).find();

  }

}

```

here is the result:

```

Benchmark                Mode  Cnt     Score   Error  Units

Re2jBenchmark.javaMatch  avgt    2   175.926          ns/op

Re2jBenchmark.re2jMatch  avgt    2  1067.591          ns/op

```