Use Java 17

java/.mvn/jvm.config

@@ -0,0 +1,10 @@
+--add-exports jdk.compiler/com.sun.tools.javac.api=ALL-UNNAMED
+--add-exports jdk.compiler/com.sun.tools.javac.file=ALL-UNNAMED
+--add-exports jdk.compiler/com.sun.tools.javac.main=ALL-UNNAMED
+--add-exports jdk.compiler/com.sun.tools.javac.model=ALL-UNNAMED
+--add-exports jdk.compiler/com.sun.tools.javac.parser=ALL-UNNAMED
+--add-exports jdk.compiler/com.sun.tools.javac.processing=ALL-UNNAMED
+--add-exports jdk.compiler/com.sun.tools.javac.tree=ALL-UNNAMED
+--add-exports jdk.compiler/com.sun.tools.javac.util=ALL-UNNAMED
+--add-opens jdk.compiler/com.sun.tools.javac.code=ALL-UNNAMED
+--add-opens jdk.compiler/com.sun.tools.javac.comp=ALL-UNNAMED

java/pom.xml

@@ -6,11 +6,11 @@
     <parent>
         <groupId>io.cucumber</groupId>
         <artifactId>cucumber-parent</artifactId>
-        <version>4.5.0</version>
+        <version>5.0.0-SNAPSHOT</version>
     </parent>
 
     <artifactId>ci-environment</artifactId>
-    <version>12.0.1-SNAPSHOT</version>
+    <version>13.0.0-SNAPSHOT</version>
     <packaging>jar</packaging>
     <name>Cucumber CiEnvironment</name>
     <description>Detect CI Environment from environment variables</description>
@@ -49,6 +49,12 @@
 
     <dependencies>
 
+        <dependency>
+            <groupId>org.jspecify</groupId>
+            <artifactId>jspecify</artifactId>
+            <version>1.0.0</version>
+        </dependency>
+
         <dependency>
             <groupId>org.junit.jupiter</groupId>
             <artifactId>junit-jupiter</artifactId>
@@ -109,10 +115,6 @@
             <plugin>
                 <groupId>org.apache.maven.plugins</groupId>
                 <artifactId>maven-compiler-plugin</artifactId>
-                <configuration>
-<!--                    TODO: Pull up to parent pom-->
-                    <parameters>true</parameters>
-                </configuration>
                 <executions>
                     <execution>
                         <id>generate-ci-environments</id>
@@ -127,6 +129,7 @@
                     </execution>
                 </executions>
             </plugin>
+
             <!-- Run the code generator -->
             <plugin>
                 <groupId>org.codehaus.mojo</groupId>
@@ -146,7 +149,7 @@
                             <additionalClasspathElements>
                                 ${project.build.directory}/codegen-classes
                             </additionalClasspathElements>
-                            <mainClass>Generate</mainClass>
+                            <mainClass>io.cucumber.cienvironment.Generate</mainClass>
                             <arguments>
                                 <argument>${project.build.directory}/generated-sources/ci-environments/java</argument>
                                 <argument>io/cucumber/cienvironment</argument>
@@ -173,6 +176,19 @@
                     </execution>
                 </executions>
             </plugin>
+            <plugin>
+                <groupId>org.apache.maven.plugins</groupId>
+                <artifactId>maven-checkstyle-plugin</artifactId>
+                <executions>
+                    <execution>
+                        <id>validate</id>
+                        <phase>validate</phase>
+                        <goals>
+                            <goal>check</goal>
+                        </goals>
+                    </execution>
+                </executions>
+            </plugin>
         </plugins>
     </build>
 </project>

java/src/codegen/java/Generate.java → java/src/codegen/java/io/cucumber/cienvironment/Generate.java

@@ -1,3 +1,5 @@
+package io.cucumber.cienvironment;
+
 import com.fasterxml.jackson.core.type.TypeReference;
 import com.fasterxml.jackson.databind.ObjectMapper;
 import freemarker.template.Configuration;

java/src/codegen/resources/templates/ci-environments.java.ftl → java/src/codegen/resources/io/cucumber/cienvironment/templates/ci-environments.java.ftl

@@ -4,7 +4,7 @@ import java.util.Collection;
 
 import static java.util.Arrays.asList;
 
-class CiEnvironments {
+final class CiEnvironments {
     static final Collection<CiEnvironmentImpl> TEMPLATES = asList(
 <#list ciEnvironments as ciEnvironment>
             new CiEnvironmentImpl(
@@ -20,4 +20,8 @@ class CiEnvironments {
 </#list>
 
     );
+
+    private CiEnvironments(){
+        // Utility class
+    }
 }

java/src/main/java/io/cucumber/cienvironment/CiEnvironment.java

@@ -4,14 +4,20 @@
 
 public interface CiEnvironment {
     String getName();
+
     String getUrl();
+
     Optional<String> getBuildNumber();
+
     Optional<Git> getGit();
 
     interface Git {
         String getRemote();
+
         String getRevision();
+
         Optional<String> getBranch();
+
         Optional<String> getTag();
     }
 }

java/src/main/java/io/cucumber/cienvironment/CiEnvironmentImpl.java

@@ -1,18 +1,20 @@
 package io.cucumber.cienvironment;
 
+import org.jspecify.annotations.Nullable;
+
 import java.util.Objects;
 import java.util.Optional;
 
 import static java.util.Objects.requireNonNull;
 import static java.util.Optional.ofNullable;
 
 final class CiEnvironmentImpl implements CiEnvironment {
-    public String name;
-    public String url;
-    public String buildNumber;
-    public Git git;
+    private final String name;
+    private final String url;
+    private final @Nullable String buildNumber;
+    private final @Nullable Git git;
 
-    CiEnvironmentImpl(String name, String url, String buildNumber, Git git) {
+    CiEnvironmentImpl(String name, String url, @Nullable String buildNumber, @Nullable Git git) {
         this.name = requireNonNull(name);
         this.url = requireNonNull(url);
         this.buildNumber = buildNumber;
@@ -63,12 +65,12 @@ public String toString() {
     }
 
     final static class Git implements CiEnvironment.Git {
-        public String remote;
-        public String revision;
-        public String branch;
-        public String tag;
+        private final String remote;
+        private final String revision;
+        private final @Nullable String branch;
+        private final @Nullable String tag;
 
-        Git(String remote, String revision, String branch, String tag) {
+        Git(String remote, String revision, @Nullable String branch, @Nullable String tag) {
             this.remote = requireNonNull(remote);
             this.revision = requireNonNull(revision);
             this.branch = branch;

java/src/main/java/io/cucumber/cienvironment/DetectCiEnvironment.java

@@ -1,11 +1,11 @@
 package io.cucumber.cienvironment;
 
+import org.jspecify.annotations.Nullable;
+
 import java.util.Map;
 import java.util.Optional;
 
 import static io.cucumber.cienvironment.VariableExpression.evaluate;
-import static java.util.Optional.empty;
-import static java.util.Optional.of;
 
 public final class DetectCiEnvironment {
     private DetectCiEnvironment() {
@@ -28,17 +28,17 @@ public static Optional<CiEnvironment> detectCiEnvironment(Map<String, String> en
 
     private static Optional<CiEnvironment> detect(CiEnvironment ci, Map<String, String> env) {
         String url = evaluate(ci.getUrl(), env);
-        if (url == null) return empty();
+        if (url == null) return Optional.empty();
 
-        return of(new CiEnvironmentImpl(
+        return Optional.of(new CiEnvironmentImpl(
                 ci.getName(),
                 url,
                 ci.getBuildNumber().map(buildNumber -> evaluate(buildNumber, env)).orElse(null),
                 detectGit(ci, env)
         ));
     }
 
-    private static CiEnvironmentImpl.Git detectGit(CiEnvironment ci, Map<String, String> env) {
+    private static CiEnvironmentImpl.@Nullable Git detectGit(CiEnvironment ci, Map<String, String> env) {
         String revision = evaluateRevision(ci, env);
         if (revision == null) return null;
 
@@ -58,7 +58,7 @@ private static CiEnvironmentImpl.Git detectGit(CiEnvironment ci, Map<String, Str
         );
     }
 
-    private static String evaluateRevision(CiEnvironment ci, Map<String, String> env) {
+    private static @Nullable String evaluateRevision(CiEnvironment ci, Map<String, String> env) {
         String revision = GithubEventParser.evaluateRevisionGithub(env);
         if (revision != null) return revision;
         return ci.getGit().map(git -> evaluate(git.getRevision(), env)).orElse(null);

java/src/main/java/io/cucumber/cienvironment/GithubEventParser.java

@@ -1,15 +1,20 @@
 package io.cucumber.cienvironment;
 
+import org.jspecify.annotations.Nullable;
+
 import java.io.IOException;
 import java.nio.file.Files;
-import java.nio.file.Path;
 import java.nio.file.Paths;
 import java.util.Map;
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;
 
 final class GithubEventParser {
-
+
+    private GithubEventParser(){
+        // Utility class
+    }
+
     /*
      * Evaluate the current revision on GitHub.
      *
@@ -19,16 +24,16 @@ final class GithubEventParser {
      *  * https://github.com/orgs/community/discussions/26325
      *  * https://github.com/cucumber/ci-environment/issues/86
      */
-    static String evaluateRevisionGithub(Map<String, String> env) {
+    static @Nullable String evaluateRevisionGithub(Map<String, String> env) {
         if (!"pull_request".equals(env.get("GITHUB_EVENT_NAME"))) {
             return null;
         }
-        if (env.get("GITHUB_EVENT_PATH") == null) {
+        String path = env.get("GITHUB_EVENT_PATH");
+        if (path == null) {
             return null;
         }
         try {
-            Path path = Paths.get(env.get("GITHUB_EVENT_PATH"));
-            String event = String.join(" ", Files.readAllLines(path));
+            String event = String.join(" ", Files.readAllLines(Paths.get(path)));
             return parsePullRequestHeadSha(event);
         } catch (IOException e) {
             return null;
@@ -67,7 +72,7 @@ static String evaluateRevisionGithub(Map<String, String> env) {
                     // End of object
                     "}$");
 
-    static String parsePullRequestHeadSha(String eventJson) {
+    static @Nullable String parsePullRequestHeadSha(String eventJson) {
         // Parse json using regex. Not ideal but works for the limited input.
         Matcher matcher = GITHUB_EVENT_PATTERN.matcher(eventJson.trim());
         if (!matcher.matches()) {

java/src/main/java/io/cucumber/cienvironment/RemoveUserInfo.java

@@ -4,8 +4,12 @@
 import java.net.URISyntaxException;
 
 final class RemoveUserInfo {
+
+    private RemoveUserInfo(){
+        // Utility class
+    }
+
     static String fromUrl(String value) {
-        if (value == null) return null;
         try {
             URI uri = URI.create(value);
             return new URI(uri.getScheme(), null, uri.getHost(), uri.getPort(), uri.getPath(), uri.getQuery(), uri.getFragment()).toASCIIString();

java/src/main/java/io/cucumber/cienvironment/VariableExpression.java

@@ -1,5 +1,7 @@
 package io.cucumber.cienvironment;
 
+import org.jspecify.annotations.Nullable;
+
 import java.util.Map;
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;
@@ -13,10 +15,10 @@ private VariableExpression() {
 
     }
 
-    static String evaluate(String expression, Map<String, String> env) {
+    static @Nullable String evaluate(@Nullable String expression, Map<String, String> env) {
         if (expression == null) return null;
         Matcher variableMatcher = variablePattern.matcher(expression);
-        StringBuffer sb = new StringBuffer();
+        StringBuilder sb = new StringBuilder();
         while (variableMatcher.find()) {
             String variable = variableMatcher.group(1);
             String value = getValue(env, variable);
@@ -43,7 +45,7 @@ static String evaluate(String expression, Map<String, String> env) {
         return sb.toString();
     }
 
-    private static String getValue(Map<String, String> env, String variable) {
+    private static @Nullable String getValue(Map<String, String> env, String variable) {
         if (variable.contains("*")) {
             Pattern pattern = Pattern.compile(variable.replace("*", ".*"));
             // GoCD env var with dynamic "material" name

java/src/main/java/io/cucumber/cienvironment/package-info.java

@@ -0,0 +1,4 @@
+@NullMarked
+package io.cucumber.cienvironment;
+
+import org.jspecify.annotations.NullMarked;

java/src/test/java/io/cucumber/CiEnvironmentExample.java

@@ -2,11 +2,14 @@
 
 import io.cucumber.cienvironment.CiEnvironment;
 
-import java.util.Optional;
-
 import static io.cucumber.cienvironment.DetectCiEnvironment.detectCiEnvironment;
 
-public class CiEnvironmentExample {
+public final class CiEnvironmentExample {
+
+    private CiEnvironmentExample(){
+        // Demo
+    }
+
     public static void main(String[] args) {
         CiEnvironment ciEnvironment = detectCiEnvironment(System.getenv()).orElseThrow(() -> new RuntimeException("No CI environment detected"));
         System.out.println("ciEnvironment = " + ciEnvironment);

java/src/test/java/io/cucumber/cienvironment/DetectCiEnvironmentTest.java

@@ -1,7 +1,6 @@
 package io.cucumber.cienvironment;
 
-import com.fasterxml.jackson.databind.DeserializationFeature;
-import com.fasterxml.jackson.databind.ObjectMapper;
+import org.jspecify.annotations.Nullable;
 import org.junit.jupiter.api.extension.ParameterContext;
 import org.junit.jupiter.params.ParameterizedTest;
 import org.junit.jupiter.params.converter.ArgumentConversionException;
@@ -30,7 +29,7 @@
 
 class DetectCiEnvironmentTest {
 
-    private static List<Path> acceptance_tests_pass() throws IOException {
+    static List<Path> acceptance_tests_pass() throws IOException {
         List<Path> paths = new ArrayList<>();
         try  (DirectoryStream<Path> testdata = newDirectoryStream(Paths.get("..", "testdata", "src"), "*.txt")){
             testdata.forEach(paths::add);
@@ -62,14 +61,18 @@ public CiEnvironment getExpected() {
 
     static class Converter implements ArgumentConverter {
         @Override
-        public Expectation convert(Object source, ParameterContext context) throws ArgumentConversionException {
+        public Expectation convert(@Nullable Object source, @Nullable ParameterContext context) throws ArgumentConversionException {
+            if (source == null) {
+                throw new ArgumentConversionException("Could not convert null");
+            }
+
             Path path = (Path) source;
             Map<String, String> env = new HashMap<>();
 
             try (BufferedReader in = newBufferedReader(path)){
                 String line;
                 while ((line = in.readLine()) != null) {
-                    String[] parts = line.split("=");
+                    String[] parts = line.split("=", 2);
 
                     if (parts.length == 1) {
                         env.put(parts[0], "");

java/src/test/java/io/cucumber/cienvironment/GitHubPullRequestIntegrationTest.java

@@ -9,6 +9,7 @@
 import java.util.Map;
 
 import static io.cucumber.cienvironment.DetectCiEnvironment.detectCiEnvironment;
+import static java.util.Objects.requireNonNull;
 import static org.junit.jupiter.api.Assertions.assertEquals;
 
 class GitHubPullRequestIntegrationTest {
@@ -28,7 +29,8 @@ private static String parseRevisionWithRegularExpression(Map<String, String> env
     }
 
     private static String parsePullRequestHeadShaWithJackson(Map<String, String> env) throws IOException {
-        File file = new File(env.get("GITHUB_EVENT_PATH"));
+        String githubEventPath = requireNonNull(env.get("GITHUB_EVENT_PATH"));
+        File file = new File(githubEventPath);
         JsonNode event = Jackson.OBJECT_MAPPER.readTree(file);
         return event.get("pull_request").get("head").get("sha").textValue();
     }