xuxiaowei-com-cn · Oct 2, 2026 · Oct 2, 2026 · Oct 2, 2026
@@ -46,7 +46,7 @@ jobs:
       fail-fast: false
       matrix:
         os: [ ubuntu-latest ]
-        jre: [ 17, 21, 25, 26 ] # Test on all supported LTS and latest JDK.
+        jre: [ 17, 21, 25, 26, 27 ] # Test on all supported LTS and latest JDK.
         include:
           - os: windows-latest
             jre: 26 # Test on the latest JDK for speeds.
@@ -77,7 +77,7 @@ jobs:
       fail-fast: false
       matrix:
         os: [ ubuntu-latest ]
-        jre: [ 17, 21, 25, 26 ] # Test on all supported LTS and latest JDK.
+        jre: [ 17, 21, 25, 26, 27 ] # Test on all supported LTS and latest JDK.
         include:
           - os: windows-latest
             jre: 26 # Test on the latest JDK for speeds.

diff --git a/CHANGES.md b/CHANGES.md
@@ -13,6 +13,7 @@ We adhere to the [keepachangelog](https://keepachangelog.com/en/1.0.0/) format (
 
 ### Changes
 - Bump default Eclipse JDT formatter version from `4.40` to `4.41`.
+- Java formatters (google-java-format, palantir-java-format, cleanthat) no longer rely on a hardcoded list of `com.sun.*` internal packages. The required packages are discovered in the `jdk.compiler` module at runtime, which improves support for newer JDKs such as JDK 27. ([#3128](https://github.com/diffplug/spotless/issues/3128))
 
 ## [4.10.3] - 2026-09-25
 

diff --git a/lib/src/main/java/com/diffplug/spotless/java/ModuleHelper.java b/lib/src/main/java/com/diffplug/spotless/java/ModuleHelper.java
@@ -22,36 +22,30 @@
 import java.lang.reflect.Modifier;
 import java.util.ArrayList;
 import java.util.Collection;
-import java.util.HashMap;
 import java.util.List;
-import java.util.Map;
-
-import javax.annotation.Nullable;
 
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
 import com.diffplug.spotless.Jvm;
 
-import edu.umd.cs.findbugs.annotations.SuppressFBWarnings;
 import sun.misc.Unsafe;
 
+/**
+ * Some Java formatters (google-java-format, palantir-java-format, cleanthat) need access to
+ * the internal packages of the JDK compiler module. Instead of hardcoding those package names,
+ * which are JDK internals that may be renamed or removed, we enumerate and open every package
+ * of that module.
+ */
 final class ModuleHelper {
 	private static final Logger LOGGER = LoggerFactory.getLogger(ModuleHelper.class);
 
+	/** The module which owns the packages that the Java formatters above require. */
+	private static final String REQUIRED_MODULE = "jdk.compiler";
+
 	// prevent direct instantiation
 	private ModuleHelper() {}
 
-	private static final Map<String, String> REQUIRED_PACKAGES_TO_TEST_CLASSES = new HashMap<>();
-
-	static {
-		REQUIRED_PACKAGES_TO_TEST_CLASSES.putIfAbsent("com.sun.tools.javac.util", "Context");
-		REQUIRED_PACKAGES_TO_TEST_CLASSES.putIfAbsent("com.sun.tools.javac.file", "CacheFSInfo");
-		REQUIRED_PACKAGES_TO_TEST_CLASSES.putIfAbsent("com.sun.tools.javac.tree", "TreeTranslator");
-		REQUIRED_PACKAGES_TO_TEST_CLASSES.putIfAbsent("com.sun.tools.javac.parser", "Tokens$TokenKind");
-		REQUIRED_PACKAGES_TO_TEST_CLASSES.putIfAbsent("com.sun.tools.javac.api", "DiagnosticFormatter$PositionKind");
-	}
-
 	private static boolean checkDone;
 
 	public static synchronized void doOpenInternalPackagesIfRequired() {
@@ -67,9 +61,8 @@ public static synchronized void doOpenInternalPackagesIfRequired() {
 				if (!failedToOpen.isEmpty()) {
 					final StringBuilder message = new StringBuilder();
 					message.append("WARNING: Some required internal classes are unavailable. Please consider adding the following JVM arguments\n");
-					message.append("WARNING: ");
 					for (String name : failedToOpen) {
-						message.append("--add-opens jdk.compiler/%s=ALL-UNNAMED".formatted(name));
+						message.append("WARNING: --add-opens %s/%s=ALL-UNNAMED%n".formatted(REQUIRED_MODULE, name));
 					}
 					LOGGER.warn("{}", message);
 				}
@@ -79,34 +72,31 @@ public static synchronized void doOpenInternalPackagesIfRequired() {
 		}
 	}
 
-	@SuppressFBWarnings("REC_CATCH_EXCEPTION") // workaround JDK11
+	/** @return the packages of {@link #REQUIRED_MODULE} which are not open to the module calling this code. */
 	private static List<String> unavailableRequiredPackages() {
+		final Module callerModule = ModuleHelper.class.getModule();
 		final List<String> packages = new ArrayList<>();
-		for (Map.Entry<String, String> e : REQUIRED_PACKAGES_TO_TEST_CLASSES.entrySet()) {
-			final String key = e.getKey();
-			final String value = e.getValue();
-			try {
-				final Class<?> clazz = Class.forName(key + "." + value);
-				if (clazz.isEnum()) {
-					clazz.getMethod("values").invoke(null);
-				} else {
-					clazz.getDeclaredConstructor().newInstance();
+		for (Module module : requiredModules()) {
+			for (String name : module.getPackages()) {
+				if (!module.isOpen(name, callerModule)) {
+					packages.add(name);
 				}
-			} catch (IllegalAccessException ex) {
-				packages.add(key);
-			} catch (Exception ignore) {
-				// in old versions of JDK some classes could be unavailable
 			}
 		}
 		return packages;
 	}
 
-	@SuppressWarnings("unchecked")
-	private static void openPackages(Collection<String> packagesToOpen) throws Throwable {
-		final Collection<?> modules = allModules();
-		if (modules == null) {
-			return;
+	private static List<Module> requiredModules() {
+		final List<Module> modules = new ArrayList<>();
+		for (Module module : ModuleLayer.boot().modules()) {
+			if (REQUIRED_MODULE.equals(module.getName())) {
+				modules.add(module);
+			}
 		}
+		return modules;
+	}
+
+	private static void openPackages(Collection<String> packagesToOpen) throws Throwable {
 		final Field unsafeField = Unsafe.class.getDeclaredField("theUnsafe");
 		unsafeField.setAccessible(true);
 		final Unsafe unsafe = (Unsafe) unsafeField.get(null);
@@ -115,30 +105,14 @@ private static void openPackages(Collection<String> packagesToOpen) throws Throw
 				unsafe.staticFieldBase(implLookupField),
 				unsafe.staticFieldOffset(implLookupField));
 		final MethodHandle modifiers = lookup.findSetter(Method.class, "modifiers", Integer.TYPE);
-		final Method exportMethod = Class.forName("java.lang.Module").getDeclaredMethod("implAddOpens", String.class);
-		modifiers.invokeExact(exportMethod, Modifier.PUBLIC);
-		for (Object module : modules) {
-			final Collection<String> packages = (Collection<String>) module.getClass().getMethod("getPackages").invoke(module);
-			for (String name : packages) {
+		final Method addOpensMethod = Module.class.getDeclaredMethod("implAddOpens", String.class);
+		modifiers.invokeExact(addOpensMethod, Modifier.PUBLIC);
+		for (Module module : requiredModules()) {
+			for (String name : module.getPackages()) {
 				if (packagesToOpen.contains(name)) {
-					exportMethod.invoke(module, name);
+					addOpensMethod.invoke(module, name);
 				}
 			}
 		}
 	}
-
-	@Nullable @SuppressFBWarnings("REC_CATCH_EXCEPTION") // workaround JDK11
-	private static Collection<?> allModules() {
-		// calling ModuleLayer.boot().modules() by reflection
-		try {
-			final Object boot = Class.forName("java.lang.ModuleLayer").getMethod("boot").invoke(null);
-			if (boot == null) {
-				return null;
-			}
-			final Object modules = boot.getClass().getMethod("modules").invoke(boot);
-			return (Collection<?>) modules;
-		} catch (Exception ignore) {
-			return null;
-		}
-	}
 }
diff --git a/plugin-gradle/CHANGES.md b/plugin-gradle/CHANGES.md
@@ -6,6 +6,7 @@ We adhere to the [keepachangelog](https://keepachangelog.com/en/1.0.0/) format (
 
 ### Changes
 - Bump default `eclipse` version from `4.40` to `4.41`.
+- No longer hardcode the `com.sun.*` internal packages required by the Java formatters, improving support for newer JDKs such as JDK 27. ([#3128](https://github.com/diffplug/spotless/issues/3128))
 
 ## [8.10.3] - 2026-09-25
 ### Changes

diff --git a/plugin-maven/CHANGES.md b/plugin-maven/CHANGES.md
@@ -6,6 +6,7 @@ We adhere to the [keepachangelog](https://keepachangelog.com/en/1.0.0/) format (
 
 ### Changes
 - Bump default `eclipse` version from `4.40` to `4.41`.
+- No longer hardcode the `com.sun.*` internal packages required by the Java formatters, improving support for newer JDKs such as JDK 27. ([#3128](https://github.com/diffplug/spotless/issues/3128))
 
 ## [3.10.3] - 2026-09-25
 ### Changes

diff --git a/plugin-maven/src/test/java/com/diffplug/spotless/maven/MavenIntegrationHarness.java b/plugin-maven/src/test/java/com/diffplug/spotless/maven/MavenIntegrationHarness.java
@@ -91,16 +91,8 @@ public class MavenIntegrationHarness extends ResourceHarness {
 	void gitAttributes() throws IOException {
 		setFile(".gitattributes").toContent("* text eol=lf");
 		if (Jvm.version() >= 16) {
-			// for GJF https://github.com/diffplug/spotless/issues/834
-			setFile(".mvn/jvm.config").toContent(
-					"--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.parser=ALL-UNNAMED"
-							+ " --add-exports jdk.compiler/com.sun.tools.javac.tree=ALL-UNNAMED"
-							+ " --add-exports jdk.compiler/com.sun.tools.javac.util=ALL-UNNAMED"
-							// this last line is for Detekt
-							+ // this last line is for Detekt
-							" --add-opens java.base/java.lang=ALL-UNNAMED");
+			// this line is for Detekt
+			setFile(".mvn/jvm.config").toContent("--add-opens java.base/java.lang=ALL-UNNAMED");
 		}
 		// copy the mvnw resources
 		copy("mvnw").setExecutable(true);

diff --git a/testlib/src/main/resources/java/importsorter/JavaCodeSortedLexicographic.test b/testlib/src/main/resources/java/importsorter/JavaCodeSortedLexicographic.test
@@ -13,5 +13,5 @@ import com.example.Test.Nested;
 import com.example.a.A;
 import com.example.b;
 import com.example.c.C;
-import com.sun.jna.platform.win32.COM.Unknown;
-import com.sun.jna.platform.win32.Guid.CLSID;
+import com.jna.platform.win32.COM.Unknown;
+import com.jna.platform.win32.Guid.CLSID;
diff --git a/testlib/src/main/resources/java/importsorter/JavaCodeSortedSemanticSort.test b/testlib/src/main/resources/java/importsorter/JavaCodeSortedSemanticSort.test
@@ -13,5 +13,5 @@ import com.example.Test.Nested;
 import com.example.b;
 import com.example.a.A;
 import com.example.c.C;
-import com.sun.jna.platform.win32.Guid.CLSID;
-import com.sun.jna.platform.win32.COM.Unknown;
+import com.jna.platform.win32.Guid.CLSID;
+import com.jna.platform.win32.COM.Unknown;
diff --git a/testlib/src/main/resources/java/importsorter/JavaCodeUnsortedSemanticSort.test b/testlib/src/main/resources/java/importsorter/JavaCodeUnsortedSemanticSort.test
@@ -7,8 +7,8 @@ import com.example.Test.Nested;
 import com.example.Test;
 import com.example.Test.*;
 
-import com.sun.jna.platform.win32.COM.Unknown;
-import com.sun.jna.platform.win32.Guid.CLSID;
+import com.jna.platform.win32.COM.Unknown;
+import com.jna.platform.win32.Guid.CLSID;
 
 import com.example.a.A;
 import com.example.b;

diff --git a/testlib/src/test/java/com/diffplug/spotless/java/ImportOrderStepTest.java b/testlib/src/test/java/com/diffplug/spotless/java/ImportOrderStepTest.java
@@ -105,7 +105,7 @@ void lexicographicSort() {
 
 	@Test
 	void semanticSort() {
-		FormatterStep step = ImportOrderStep.forJava().createFrom(false, true, Set.of("com.sun.jna.platform.win32.COM"),
+		FormatterStep step = ImportOrderStep.forJava().createFrom(false, true, Set.of("com.jna.platform.win32.COM"),
 				Set.of("com.example.b"), createTestFile("java/importsorter/import.properties"));
 		StepHarness.forStep(step).testResource("java/importsorter/JavaCodeUnsortedSemanticSort.test", "java/importsorter/JavaCodeSortedSemanticSort.test");
 	}