[Core] Add faster UUID generator selectable through SPI

.revapi/api-changes.json

@@ -181,6 +181,18 @@
             "code": "java.method.finalMethodAddedToNonFinalClass",
             "new": "method java.lang.Long io.cucumber.core.internal.com.fasterxml.jackson.databind.deser.std.StdDeserializer<T>::_parseLong(io.cucumber.core.internal.com.fasterxml.jackson.databind.DeserializationContext, java.lang.String) throws java.io.IOException",
             "justification": "Internal API"
+          },
+          {
+            "ignore": true,
+            "code": "java.method.addedToInterface",
+            "new": "method java.lang.Class<? extends io.cucumber.core.eventbus.UuidGenerator> io.cucumber.core.options.CucumberOptionsAnnotationParser.CucumberOptions::uuidGenerator()",
+            "justification": "Internal API"
+          },
+          {
+            "ignore": true,
+            "code": "java.method.addedToInterface",
+            "new": "method java.lang.Class<? extends io.cucumber.core.eventbus.UuidGenerator> io.cucumber.core.runner.Options::getUuidGeneratorClass()",
+            "justification": "Internal API"
           }
         ]
       }
@@ -331,6 +343,12 @@
             "code": "java.method.defaultMethodAddedToInterface",
             "new": "method java.util.Set<org.testng.ITestNGMethod> org.testng.ITestNGMethod::upstreamDependencies()",
             "justification": "Third party api change"
+          },
+          {
+            "ignore": true,
+            "code": "java.class.externalClassExposedInAPI",
+            "new": "interface io.cucumber.core.eventbus.UuidGenerator",
+            "justification": "Part of cucumber API"
           }
         ]
       }
@@ -383,6 +401,12 @@
             "new": "method int org.junit.platform.engine.ConfigurationParameters::size()",
             "annotation": "@org.apiguardian.api.API(status = org.apiguardian.api.API.Status.DEPRECATED, since = \"1.9\")",
             "justification": "API consumed from JUnit 5"
+          },
+          {
+            "ignore": true,
+            "code": "java.class.externalClassExposedInAPI",
+            "new": "interface io.cucumber.core.eventbus.UuidGenerator",
+            "justification": "Part of cucumber API"
           }
         ]
       }

CHANGELOG.md

@@ -11,6 +11,9 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+### Added
+- [Core] Improved event bus performance using UUID generator selectable through SPI ([#2703](https://github.com/cucumber/cucumber-jvm/pull/2703) Julien Kronegg)
+
 ## [7.11.1] - 2023-01-27
 ### Added
 - [Core] Warn when `cucumber.options` is used ([#2685](https://github.com/cucumber/cucumber-jvm/pull/2685) M.P. Korstanje)

compatibility/pom.xml

@@ -4,7 +4,7 @@
     <parent>
         <artifactId>cucumber-jvm</artifactId>
         <groupId>io.cucumber</groupId>
-        <version>7.11.2-SNAPSHOT</version>
+        <version>7.12.0-SNAPSHOT</version>
     </parent>
     <modelVersion>4.0.0</modelVersion>
 

cucumber-archetype/pom.xml

@@ -6,7 +6,7 @@
     <parent>
         <groupId>io.cucumber</groupId>
         <artifactId>cucumber-jvm</artifactId>
-        <version>7.11.2-SNAPSHOT</version>
+        <version>7.12.0-SNAPSHOT</version>
     </parent>
 
     <artifactId>cucumber-archetype</artifactId>

cucumber-bom/pom.xml

@@ -3,7 +3,7 @@
     <parent>
         <artifactId>cucumber-jvm</artifactId>
         <groupId>io.cucumber</groupId>
-        <version>7.11.2-SNAPSHOT</version>
+        <version>7.12.0-SNAPSHOT</version>
     </parent>
     <modelVersion>4.0.0</modelVersion>
     <packaging>pom</packaging>
@@ -63,97 +63,97 @@
             <dependency>
                 <groupId>io.cucumber</groupId>
                 <artifactId>cucumber-cdi2</artifactId>
-                <version>7.11.2-SNAPSHOT</version>
+                <version>7.12.0-SNAPSHOT</version>
             </dependency>
             <dependency>
                 <groupId>io.cucumber</groupId>
                 <artifactId>cucumber-core</artifactId>
-                <version>7.11.2-SNAPSHOT</version>
+                <version>7.12.0-SNAPSHOT</version>
             </dependency>
             <dependency>
                 <groupId>io.cucumber</groupId>
                 <artifactId>datatable</artifactId>
-                <version>7.11.2-SNAPSHOT</version>
+                <version>7.12.0-SNAPSHOT</version>
             </dependency>
             <dependency>
                 <groupId>io.cucumber</groupId>
                 <artifactId>datatable-matchers</artifactId>
-                <version>7.11.2-SNAPSHOT</version>
+                <version>7.12.0-SNAPSHOT</version>
             </dependency>
             <dependency>
                 <groupId>io.cucumber</groupId>
                 <artifactId>cucumber-deltaspike</artifactId>
-                <version>7.11.2-SNAPSHOT</version>
+                <version>7.12.0-SNAPSHOT</version>
             </dependency>
             <dependency>
                 <groupId>io.cucumber</groupId>
                 <artifactId>docstring</artifactId>
-                <version>7.11.2-SNAPSHOT</version>
+                <version>7.12.0-SNAPSHOT</version>
             </dependency>
             <dependency>
                 <groupId>io.cucumber</groupId>
                 <artifactId>cucumber-gherkin</artifactId>
-                <version>7.11.2-SNAPSHOT</version>
+                <version>7.12.0-SNAPSHOT</version>
             </dependency>
             <dependency>
                 <groupId>io.cucumber</groupId>
                 <artifactId>cucumber-gherkin-messages</artifactId>
-                <version>7.11.2-SNAPSHOT</version>
+                <version>7.12.0-SNAPSHOT</version>
             </dependency>
             <dependency>
                 <groupId>io.cucumber</groupId>
                 <artifactId>cucumber-guice</artifactId>
-                <version>7.11.2-SNAPSHOT</version>
+                <version>7.12.0-SNAPSHOT</version>
             </dependency>
             <dependency>
                 <groupId>io.cucumber</groupId>
                 <artifactId>cucumber-jakarta-cdi</artifactId>
-                <version>7.11.2-SNAPSHOT</version>
+                <version>7.12.0-SNAPSHOT</version>
             </dependency>
             <dependency>
                 <groupId>io.cucumber</groupId>
                 <artifactId>cucumber-java</artifactId>
-                <version>7.11.2-SNAPSHOT</version>
+                <version>7.12.0-SNAPSHOT</version>
             </dependency>
             <dependency>
                 <groupId>io.cucumber</groupId>
                 <artifactId>cucumber-java8</artifactId>
-                <version>7.11.2-SNAPSHOT</version>
+                <version>7.12.0-SNAPSHOT</version>
             </dependency>
             <dependency>
                 <groupId>io.cucumber</groupId>
                 <artifactId>cucumber-junit</artifactId>
-                <version>7.11.2-SNAPSHOT</version>
+                <version>7.12.0-SNAPSHOT</version>
             </dependency>
             <dependency>
                 <groupId>io.cucumber</groupId>
                 <artifactId>cucumber-junit-platform-engine</artifactId>
-                <version>7.11.2-SNAPSHOT</version>
+                <version>7.12.0-SNAPSHOT</version>
             </dependency>
             <dependency>
                 <groupId>io.cucumber</groupId>
                 <artifactId>cucumber-openejb</artifactId>
-                <version>7.11.2-SNAPSHOT</version>
+                <version>7.12.0-SNAPSHOT</version>
             </dependency>
             <dependency>
                 <groupId>io.cucumber</groupId>
                 <artifactId>cucumber-picocontainer</artifactId>
-                <version>7.11.2-SNAPSHOT</version>
+                <version>7.12.0-SNAPSHOT</version>
             </dependency>
             <dependency>
                 <groupId>io.cucumber</groupId>
                 <artifactId>cucumber-plugin</artifactId>
-                <version>7.11.2-SNAPSHOT</version>
+                <version>7.12.0-SNAPSHOT</version>
             </dependency>
             <dependency>
                 <groupId>io.cucumber</groupId>
                 <artifactId>cucumber-spring</artifactId>
-                <version>7.11.2-SNAPSHOT</version>
+                <version>7.12.0-SNAPSHOT</version>
             </dependency>
             <dependency>
                 <groupId>io.cucumber</groupId>
                 <artifactId>cucumber-testng</artifactId>
-                <version>7.11.2-SNAPSHOT</version>
+                <version>7.12.0-SNAPSHOT</version>
             </dependency>
         </dependencies>
     </dependencyManagement>

cucumber-cdi2/pom.xml

@@ -14,7 +14,7 @@
     <parent>
         <groupId>io.cucumber</groupId>
         <artifactId>cucumber-jvm</artifactId>
-        <version>7.11.2-SNAPSHOT</version>
+        <version>7.12.0-SNAPSHOT</version>
     </parent>
 
     <artifactId>cucumber-cdi2</artifactId>

cucumber-core/README.md

@@ -52,6 +52,9 @@ cucumber.plugin=                # comma separated plugin strings.
 cucumber.object-factory=        # object factory class name.
                                 # example: com.example.MyObjectFactory
 
+cucumber.uuid-generator=        # UUID generator class name.
+                                # example: com.example.MyUuidGenerator
+
 cucumber.publish.enabled        # true or false. default: false
                                 # enable publishing of test results 
 
@@ -79,6 +82,23 @@ They are  respectively responsible for discovering glue classes, registering
 step definitions, and creating instances of said glue classes. Backend and
 object factory implementations are discovered via SPI.
 
+## Event bus ##
+
+Cucumber emits events on an event bus in many cases:
+- during the feature file parsing
+- when the test scenarios are executed
+
+An event has a UUID. The UUID generator can be configured using the `cucumber.uuid-generator` property:
+
+| UUID generator                                      | Features                                | Performance [Millions UUID/second] | Typical usage example                                                                                                                                                                                                                                                          | 
+|-----------------------------------------------------|-----------------------------------------|------------------------------------|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
+| io.cucumber.core.eventbus.RandomUuidGenerator       | Thread-safe, collision-free, multi-jvm  | ~1                                 | Reports may be generated on different JVMs at the same time. A typical example would be one suite that tests against Firefox and another against Safari. The exact browser is configured through a property. These are then executed concurrently on different Gitlab runners. |
+| io.cucumber.core.eventbus.IncrementingUuidGenerator | Thread-safe, collision-free, single-jvm | ~130                               | Reports are generated on a single JVM                                                                                                                                                                                                                                          |
+
+The performance gain on real project depend on the feature size.
+
+When not specified, the `RandomUuidGenerator` is used.
+
 ## Plugin ##
 
 By implementing the Plugin interface classes can listen to execution events

cucumber-core/pom.xml

@@ -4,7 +4,7 @@
     <parent>
         <groupId>io.cucumber</groupId>
         <artifactId>cucumber-jvm</artifactId>
-        <version>7.11.2-SNAPSHOT</version>
+        <version>7.12.0-SNAPSHOT</version>
     </parent>
 
     <artifactId>cucumber-core</artifactId>

cucumber-core/src/main/java/io/cucumber/core/cli/CommandlineOptions.java

@@ -66,6 +66,8 @@ public final class CommandlineOptions {
 
     public static final String OBJECT_FACTORY = "--object-factory";
 
+    public static final String UUID_GENERATOR = "--uuid-generator";
+
     private CommandlineOptions() {
     }
 }

cucumber-core/src/main/java/io/cucumber/core/eventbus/IncrementingUuidGenerator.java

@@ -0,0 +1,40 @@
+package io.cucumber.core.eventbus;
+
+import io.cucumber.core.exception.CucumberException;
+
+import java.util.UUID;
+import java.util.concurrent.atomic.AtomicLong;
+
+/**
+ * Thread-safe and collision-free UUID generator for single JVM. This is a
+ * sequence generator and each instance has its own counter. This generator is
+ * about 100 times faster than #RandomUuidGenerator. If you use Cucumber in
+ * multi-JVM setup, you should use #RandomUuidGenerator instead. Note that the
+ * UUID version and variant is not guaranteed to be stable.
+ */
+public class IncrementingUuidGenerator implements UuidGenerator {
+    private static final AtomicLong sessionCounter = new AtomicLong(Long.MIN_VALUE);
+
+    private final long sessionId;
+    private final AtomicLong counter = new AtomicLong(Long.MIN_VALUE);
+
+    public IncrementingUuidGenerator() {
+        sessionId = sessionCounter.incrementAndGet();
+    }
+
+    /**
+     * Generate a new UUID. Will throw an exception when out of capacity.
+     * 
+     * @return                   a non-null UUID
+     * @throws CucumberException when out of capacity
+     */
+    @Override
+    public UUID get() {
+        long leastSigBits = counter.incrementAndGet();
+        if (leastSigBits == Long.MAX_VALUE) {
+            throw new CucumberException(
+                "Out of IncrementingUuidGenerator capacity. Please use the RandomUuidGenerator instead.");
+        }
+        return new UUID(sessionId, leastSigBits);
+    }
+}

cucumber-core/src/main/java/io/cucumber/core/eventbus/Options.java

@@ -0,0 +1,7 @@
+package io.cucumber.core.eventbus;
+
+public interface Options {
+
+    Class<? extends UuidGenerator> getUuidGeneratorClass();
+
+}

cucumber-core/src/main/java/io/cucumber/core/eventbus/RandomUuidGenerator.java

@@ -0,0 +1,14 @@
+package io.cucumber.core.eventbus;
+
+import java.util.UUID;
+
+/**
+ * UUID generator based on random numbers. The generator is thread-safe and
+ * supports multi-jvm usage of Cucumber.
+ */
+public class RandomUuidGenerator implements UuidGenerator {
+    @Override
+    public UUID get() {
+        return UUID.randomUUID();
+    }
+}

cucumber-core/src/main/java/io/cucumber/core/eventbus/UuidGenerator.java

@@ -0,0 +1,13 @@
+package io.cucumber.core.eventbus;
+
+import org.apiguardian.api.API;
+
+import java.util.UUID;
+import java.util.function.Supplier;
+
+/**
+ * SPI (Service Provider Interface) to generate UUIDs.
+ */
+@API(status = API.Status.STABLE)
+public interface UuidGenerator extends Supplier<UUID> {
+}

cucumber-core/src/main/java/io/cucumber/core/options/CommandlineOptionsParser.java

@@ -53,12 +53,14 @@
 import static io.cucumber.core.cli.CommandlineOptions.TAGS;
 import static io.cucumber.core.cli.CommandlineOptions.TAGS_SHORT;
 import static io.cucumber.core.cli.CommandlineOptions.THREADS;
+import static io.cucumber.core.cli.CommandlineOptions.UUID_GENERATOR;
 import static io.cucumber.core.cli.CommandlineOptions.VERSION;
 import static io.cucumber.core.cli.CommandlineOptions.VERSION_SHORT;
 import static io.cucumber.core.cli.CommandlineOptions.WIP;
 import static io.cucumber.core.cli.CommandlineOptions.WIP_SHORT;
 import static io.cucumber.core.options.ObjectFactoryParser.parseObjectFactory;
 import static io.cucumber.core.options.OptionsFileParser.parseFeatureWithLinesFile;
+import static io.cucumber.core.options.UuidGeneratorParser.parseUuidGenerator;
 import static java.nio.charset.StandardCharsets.UTF_8;
 import static java.util.Arrays.asList;
 import static java.util.stream.Collectors.joining;
@@ -167,6 +169,9 @@ private RuntimeOptionsBuilder parse(List<String> args) {
             } else if (arg.equals(OBJECT_FACTORY)) {
                 String objectFactoryClassName = removeArgFor(arg, args);
                 parsedOptions.setObjectFactoryClass(parseObjectFactory(objectFactoryClassName));
+            } else if (arg.equals(UUID_GENERATOR)) {
+                String uuidGeneratorClassName = removeArgFor(arg, args);
+                parsedOptions.setUuidGeneratorClass(parseUuidGenerator(uuidGeneratorClassName));
             } else if (arg.startsWith("-")) {
                 out.println("Unknown option: " + arg);
                 printUsage();

cucumber-core/src/main/java/io/cucumber/core/options/Constants.java

@@ -1,6 +1,7 @@
 package io.cucumber.core.options;
 
 import io.cucumber.core.runtime.ObjectFactoryServiceLoader;
+import io.cucumber.core.runtime.UuidGeneratorServiceLoader;
 
 public final class Constants {
 
@@ -118,6 +119,14 @@ public final class Constants {
      */
     public static final String OBJECT_FACTORY_PROPERTY_NAME = "cucumber.object-factory";
 
+    /**
+     * Property name used to select a specific UUID generator implementation:
+     * {@value}
+     *
+     * @see UuidGeneratorServiceLoader
+     */
+    public static final String UUID_GENERATOR_PROPERTY_NAME = "cucumber.uuid-generator";
+
     /**
      * Property name formerly used to pass command line options to Cucumber:
      * {@value} This property is no longer read by Cucumber. Please use any of