[Core] Support nested jar file systems

CHANGELOG.md

@@ -15,6 +15,9 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ### Fixed
 - [Guice] Inject static fields prior to before all hooks ([#2803](https://github.com/cucumber/cucumber-jvm/pull/2803) M.P. Korstanje)
 
+### Added
+- [Core] Support nested jar file systems (i.e. Spring Boot 3.2) ([#2830](https://github.com/cucumber/cucumber-jvm/pull/2830) M.P. Korstanje)
+
 ## [7.14.0] - 2023-09-09
 ### Changed
 - [Core] Update dependency io.cucumber:html-formatter to v20.4.0

cucumber-core/src/main/java/io/cucumber/core/resource/ClasspathSupport.java

@@ -167,7 +167,8 @@ static String nestedJarEntriesExplanation(URI uri) {
  "This typically happens when trying to run Cucumber inside a Spring Boot Executable Jar.\n" +
  "Cucumber currently doesn't support classpath scanning in nested jars.\n" +
  "\n" +
- "You can avoid this error by unpacking your application before executing.\n" +
+ "You can avoid this error by unpacking your application before executing or upgrading to Spring Boot 3.2 or higher.\n"
+ +
  "\n" +
  "Alternatively you can restrict which packages cucumber scans configuring the glue path such that " +
  "Cucumber only scans un-nested jars.\n" +

cucumber-core/src/main/java/io/cucumber/core/resource/JarUriFileSystemService.java

@@ -22,7 +22,7 @@ class JarUriFileSystemService {
  private static final String JAR_URI_SCHEME = "jar";
  private static final String JAR_URI_SCHEME_PREFIX = JAR_URI_SCHEME + ":";
  private static final String JAR_FILE_SUFFIX = ".jar";
- private static final String JAR_URI_SEPARATOR = "!";
+ private static final String JAR_URI_SEPARATOR = "!/";
 
  private static final Map<URI, FileSystem> openFiles = new HashMap<>();
  private static final Map<URI, AtomicInteger> referenceCount = new HashMap<>();
@@ -67,13 +67,14 @@ private static boolean hasFileUriSchemeWithJarExtension(URI uri) {
  }
 
  static CloseablePath open(URI uri) throws URISyntaxException, IOException {
- if (hasJarUriScheme(uri)) {
- return handleJarUriScheme(uri);
- }
+ assert supports(uri);
  if (hasFileUriSchemeWithJarExtension(uri)) {
  return handleFileUriSchemeWithJarExtension(uri);
  }
- throw new IllegalArgumentException("Unsupported uri " + uri.toString());
+ if (isSpringBoot31OrLower(uri)) {
+ return handleSpringBoot31JarUri(uri);
+ }
+ return handleJarUriScheme(uri);
  }
 
  private static CloseablePath handleFileUriSchemeWithJarExtension(URI uri) throws IOException, URISyntaxException {
@@ -82,22 +83,44 @@ private static CloseablePath handleFileUriSchemeWithJarExtension(URI uri) throws
  }
 
  private static CloseablePath handleJarUriScheme(URI uri) throws IOException, URISyntaxException {
- String[] parts = uri.toString().split(JAR_URI_SEPARATOR);
- // Regular jar schemes
- if (parts.length <= 2) {
-  String jarUri = parts[0];
-  String jarPath = parts.length == 2 ? parts[1] : "/";
- return open(new URI(jarUri), fileSystem -> fileSystem.getPath(jarPath));
+ // Regular Jar Uris
+ // Format: jar:<url>!/[<entry>]
+ String uriString = uri.toString();
+ int lastJarUriSeparator = uriString.lastIndexOf(JAR_URI_SEPARATOR);
+ if (lastJarUriSeparator < 0) {
+ throw new IllegalArgumentException(String.format("jar uri '%s' must contain '%s'", uri, JAR_URI_SEPARATOR));
  }
+ String url = uriString.substring(0, lastJarUriSeparator);
+ String entry = uriString.substring(lastJarUriSeparator + 1);
+ return open(new URI(url), fileSystem -> fileSystem.getPath(entry));
+ }
 
- // Spring boot jar scheme
+ private static boolean isSpringBoot31OrLower(URI uri) {
+ // Starting Spring Boot 3.2 the nested scheme is used. This works with
+ // regular jar file handling and doesn't need a workaround.
+ // Example 3.2:
+ // jar:nested:/dir/myjar.jar/!/BOOT-INF/lib/nested.jar!/com/example/MyClass.class
+ // Example 3.1:
+ // jar:file:/dir/myjar.jar/!/BOOT-INF/lib/nested.jar!/com/example/MyClass.class
+ String schemeSpecificPart = uri.getSchemeSpecificPart();
+ return schemeSpecificPart.startsWith("file:") && schemeSpecificPart.contains("!/BOOT-INF");
+ }
+
+ private static CloseablePath handleSpringBoot31JarUri(URI uri) throws IOException, URISyntaxException {
+ // Spring boot 3.1 jar scheme
+ // Examples:
+ // jar:file:/home/user/application.jar!/BOOT-INF/lib/dependency.jar!/com/example/dependency/resource.txt
+ // jar:file:/home/user/application.jar!/BOOT-INF/classes!/com/example/package/resource.txt
+ String[] parts = uri.toString().split("!");
  String jarUri = parts[0];
  String jarEntry = parts[1];
  String subEntry = parts[2];
  if (jarEntry.endsWith(JAR_FILE_SUFFIX)) {
  throw new CucumberException(nestedJarEntriesExplanation(uri));
  }
+ // We're looking directly at the files in the jar, so we construct the
+ // file path by concatenating the jarEntry and subEntry without the jar
+ // uri separator.
  return open(new URI(jarUri), fileSystem -> fileSystem.getPath(jarEntry + subEntry));
  }
-
 }

cucumber-core/src/test/java/io/cucumber/core/resource/ResourceScannerTest.java

@@ -159,6 +159,29 @@ void scanForResourcesJarUri() {
  assertThat(resources, contains(resourceUri));
  }
 
+ @Test
+ void scanForResourcesJarUriMalformed() {
+ URI jarFileUri = new File("src/test/resources/io/cucumber/core/resource/test/jar-resource.jar").toURI();
+ URI resourceUri = URI
+ .create("jar:file://" + jarFileUri.getSchemeSpecificPart() + "/com/example/package-jar-resource.txt");
+ IllegalArgumentException exception = assertThrows(
+ IllegalArgumentException.class,
+ () -> resourceScanner.scanForResourcesUri(resourceUri));
+ assertThat(exception.getMessage(),
+ containsString("jar uri '" + resourceUri + "' must contain '!/'"));
+ }
+
+ @Test
+ void scanForResourcesJarUriMissingEntry() {
+ URI jarFileUri = new File("src/test/resources/io/cucumber/core/resource/test/jar-resource.jar").toURI();
+ URI resourceUri = URI.create("jar:file://" + jarFileUri.getSchemeSpecificPart() + "");
+ IllegalArgumentException exception = assertThrows(
+ IllegalArgumentException.class,
+ () -> resourceScanner.scanForResourcesUri(resourceUri));
+ assertThat(exception.getMessage(),
+ containsString("jar uri '" + resourceUri + "' must contain '!/'"));
+ }
+
  @Test
  void scanForResourcesNestedJarUri() {
  URI jarFileUri = new File("src/test/resources/io/cucumber/core/resource/test/spring-resource.jar").toURI();