Бенчмарк для статьи на хабре

DecodeBenchmark.java

@BenchmarkMode(Mode.AverageTime)
@OutputTimeUnit(TimeUnit.NANOSECONDS)
@Fork(jvmArgsAppend = {"-Xms2g", "-Xmx2g"})
public class DecodeBenchmark {

  @Benchmark
  public String uriDecode(Data data) {
    return uriDecode(data.encoded, data.charset);
  }

  private static String uriDecode(String source, Charset charset) {
    int length = source.length();
    if (length == 0) {
      return source;
    }
    Objects.requireNonNull(charset, "Charset must not be null");

    ByteArrayOutputStream baos = new ByteArrayOutputStream(length);
    boolean changed = false;
    for (int i = 0; i < length; i++) {
      int ch = source.charAt(i);
      if (ch == '%') {
        if (i + 2 < length) {
          char hex1 = source.charAt(i + 1);
          char hex2 = source.charAt(i + 2);
          int u = Character.digit(hex1, 16);
          int l = Character.digit(hex2, 16);
          if (u == -1 || l == -1) {
            throw new IllegalArgumentException("Invalid encoded sequence \"" + source.substring(i) + "\"");
          }
          baos.write((char) ((u << 4) + l));
          i += 2;
          changed = true;
        }
        else {
          throw new IllegalArgumentException("Invalid encoded sequence \"" + source.substring(i) + "\"");
        }
      }
      else {
        baos.write(ch);
      }
    }
    return (changed ? new String(baos.toByteArray(), charset) : source);
//    return (changed ? baos.toString( charset) : source);
  }

  @State(Scope.Thread)
  public static class Data {
    private final Charset charset = Charset.defaultCharset();
    private String encoded;

    @Setup
    public void setup(){
      String utf8Url = "https://ru.wikipedia.org/wiki/Организация_Объединённых_Наций";
      encoded = URLEncoder.encode(utf8Url, charset);
    }
  }
}