java: bad performance in StringUtils

[jkronegg]

👓 What did you see?

There are performance issues in https://github.com/cucumber/gherkin/blob/main/java/src/main/java/io/cucumber/gherkin/StringUtils.java because the String.replaceAll method used in the StringUtils class makes a new Pattern.compile at every call.

The impact is that on a project with ~150 teststeps and ~400 test scenarios, the feature parser uses 0.68% of the total CPU time in the StringUtils.trim() method (about 50 ms). That's not a lot, but the still worth the investment effort.

✅ What did you expect to see?

I expect the performance StringUtils methods to run faster. It's easy to do so by precompiling the Pattern :

Method	Description	ops/s
StringUtilsBenchmark.trim0	original version	1'162'751 ± 74'322
StringUtilsBenchmark.trim1	precomputed Pattern.compile	3'861'664 ± 87'344

📦 Which tool/library version are you using?

Cucumber 7.10.1

🔬 How could we reproduce it?

Steps to reproduce the behavior:

1. Create a Maven project with the following dependencies:

   <dependency>
     <groupId>io.cucumber</groupId>
     <artifactId>cucumber-java</artifactId>
     <version>${cucumber.version}</version>
     <scope>test</scope>
   </dependency>
   <dependency>
     <groupId>io.cucumber</groupId>
     <artifactId>cucumber-junit-platform-engine</artifactId>
     <version>${cucumber.version}</version>
     <scope>test</scope>
   </dependency>
   <dependency>
     <groupId>io.cucumber</groupId>
     <artifactId>cucumber-picocontainer</artifactId>
     <version>${cucumber.version}</version>
     <scope>test</scope>
   </dependency>
   <dependency>
      <groupId>org.openjdk.jmh</groupId>
      <artifactId>jmh-generator-annprocess</artifactId>
      <version>1.36</version>
      <scope>test</scope>
   </dependency>
   

2. Run the JMH benchmark from
   gherkin.zip