Use a message based json formatter (#2888)

Replace the JsonFormatter with the message based implementation from cucumber-json-formatter[1].

This achieves several goals:

* Move the internal code base away from the events from the plugin module.
* Extract common parts of Cucumber into modules that can be shared.
* Allows for more rigorous testing of a poorly defined format

1. https://github.com/cucumber/cucumber-json-formatter

Author: mpkorstanje

.revapi/api-changes.json

@@ -71,22 +71,12 @@
   ],
   "internal": [
     {
-      "extension": "revapi.differences",
-      "id": "internal-api-issues",
       "ignore": true,
-      "configuration": {
-        "differences": [
-          {
-            "ignore": true,
-            "code": "java.method.visibilityIncreased",
-            "old": "method io.cucumber.core.eventbus.UuidGenerator io.cucumber.core.runtime.UuidGeneratorServiceLoader::loadUuidGenerator()",
-            "new": "method io.cucumber.core.eventbus.UuidGenerator io.cucumber.core.runtime.UuidGeneratorServiceLoader::loadUuidGenerator()",
-            "oldVisibility": "package",
-            "newVisibility": "public",
-            "justification": "Expose internal API to other internal components"
-          }
-        ]
-      }
+      "code": "java.class.nowImplementsInterface",
+      "old": "class io.cucumber.core.plugin.JsonFormatter",
+      "new": "class io.cucumber.core.plugin.JsonFormatter",
+      "interface": "io.cucumber.plugin.ConcurrentEventListener",
+      "justification": "The JsonFormatter is consumed by Cucumber"
     }
   ],
   "testng": [

CHANGELOG.md

@@ -18,14 +18,16 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ### Deprecated
 - [Core] Deprecate `--i18n` options ([#3053](https://github.com/cucumber/cucumber-jvm/pull/3053) M.P. Korstanje)
 
+### Changed
+- [Core] Use a [message based Cucumber JSON Formatter](https://github.com/cucumber/cucumber-json-formatter) ([##2888](https://github.com/cucumber/cucumber-jvm/pull/#2888) M.P. Korstanje)
+
 ## [7.27.2] - 2025-08-18
 ### Fixed
 - [Core] Intellij prints summary printed when executing concurrently ([#3049](https://github.com/cucumber/cucumber-jvm/pull/3049) M.P. Korstanje)
 
 ### Added
 - [Core] Add custom UuidGenerator to Runtime.Builder ([#3039](https://github.com/cucumber/junit-xml-formatter/pull/3039) Christoph Läubrich, M.P. Korstanje)
 
-
 ## [7.27.1] - 2025-08-17
 ### Fixed
 - [Core] Format time in JUnit XML report as `xs:float` ([junit-xml-formatter/#83](https://github.com/cucumber/junit-xml-formatter/pull/83) M.P. Korstanje)

cucumber-bom/pom.xml

@@ -15,6 +15,7 @@
     <properties>
         <ci-environment.version>10.0.1</ci-environment.version>
         <cucumber-expressions.version>18.0.1</cucumber-expressions.version>
+        <cucumber-json-formatter.version>0.1.1</cucumber-json-formatter.version>
         <gherkin.version>34.0.0</gherkin.version>
         <html-formatter.version>21.13.0</html-formatter.version>
         <junit-xml-formatter.version>0.8.1</junit-xml-formatter.version>
@@ -38,6 +39,11 @@
                 <artifactId>cucumber-expressions</artifactId>
                 <version>${cucumber-expressions.version}</version>
             </dependency>
+            <dependency>
+                <groupId>io.cucumber</groupId>
+                <artifactId>cucumber-json-formatter</artifactId>
+                <version>${cucumber-json-formatter.version}</version>
+            </dependency>
             <dependency>
                 <groupId>io.cucumber</groupId>
                 <artifactId>gherkin</artifactId>

cucumber-core/pom.xml

@@ -80,6 +80,10 @@
             <groupId>io.cucumber</groupId>
             <artifactId>cucumber-expressions</artifactId>
         </dependency>
+        <dependency>
+            <groupId>io.cucumber</groupId>
+            <artifactId>cucumber-json-formatter</artifactId>
+        </dependency>
         <dependency>
             <groupId>io.cucumber</groupId>
             <artifactId>datatable</artifactId>