Reinforce the check on the sealed classes in JEP397

The change is to add more check on the sealed classes
specified in JEP397: Sealed Classes (Second Preview)

Related: eclipse-openj9#11273

Signed-off-by: Cheng Jin <jincheng@ca.ibm.com>

runtime/nls/j9vm/j9vm.nls

@@ -1,5 +1,5 @@
 #
-# Copyright (c) 2000, 2020 IBM Corp. and others
+# Copyright (c) 2000, 2021 IBM Corp. and others
 #
 # This program and the accompanying materials are made available under
 # the terms of the Eclipse Public License 2.0 which accompanies this
@@ -2010,3 +2010,21 @@ J9NLS_VM_ERROR_BYTECODE_OBJECTREF_CANNOT_BE_VALUE_BASED.explanation=The class ha
 J9NLS_VM_ERROR_BYTECODE_OBJECTREF_CANNOT_BE_VALUE_BASED.system_action=The JVM will throw an VirtualMachineError.
 J9NLS_VM_ERROR_BYTECODE_OBJECTREF_CANNOT_BE_VALUE_BASED.user_response=Contact the provider of the classfile for a corrected version.
 # END NON-TRANSLATABLE
+
+# Message to use when class/interface is not in the same module as its sealed super class/interface
+# argument 1 is the class name
+J9NLS_VM_CLASS_LOADING_ERROR_SEALED_SUPER_IN_DIFFERENT_MODULE=The class/interface %2$.*1$s is not in the same module as its sealed super class/interface.
+# START NON-TRANSLATABLE
+J9NLS_VM_CLASS_LOADING_ERROR_SEALED_SUPER_IN_DIFFERENT_MODULE.explanation=The specified class must be in the same module as its sealed super class/interface.
+J9NLS_VM_CLASS_LOADING_ERROR_SEALED_SUPER_IN_DIFFERENT_MODULE.system_action=The JVM will throw an IncompatibleClassChangeError.
+J9NLS_VM_CLASS_LOADING_ERROR_SEALED_SUPER_IN_DIFFERENT_MODULE.user_response=Contact the provider of the classfile for a corrected version.
+# END NON-TRANSLATABLE
+
+# Message to use when non-public class/interface is not in the same package as its sealed super class/interface
+# argument 1 is the class name
+J9NLS_VM_CLASS_LOADING_ERROR_SEALED_SUPER_IN_DIFFERENT_PACKAGE=The non-public class/interface %2$.*1$s is not in the same package as its sealed super class/interface.
+# START NON-TRANSLATABLE
+J9NLS_VM_CLASS_LOADING_ERROR_SEALED_SUPER_IN_DIFFERENT_PACKAGE.explanation=The specified non-public class must be in the same package as its sealed super class/interface.
+J9NLS_VM_CLASS_LOADING_ERROR_SEALED_SUPER_IN_DIFFERENT_PACKAGE.system_action=The JVM will throw an IncompatibleClassChangeError.
+J9NLS_VM_CLASS_LOADING_ERROR_SEALED_SUPER_IN_DIFFERENT_PACKAGE.user_response=Contact the provider of the classfile for a corrected version.
+# END NON-TRANSLATABLE

runtime/vm/createramclass.cpp

@@ -1614,6 +1614,48 @@ isClassPermittedBySealedSuper(J9ROMClass *superRomClass, U_8* className, U_16 cl
 	return result;
 }
 
+#if JAVA_SPEC_VERSION >= 16
+/**
+ * JEP 397 (second preview): if super class/interface is sealed, IncompatibleClassChangeError is throw out
+ * if one of the following conditions is false:
+ * (1) the inheriting subclass is not in the same module as its super class/interface;
+ * (2) the inheriting subclass (non-public) is not in the same package as its super class/interface.
+ *
+ * @param vmThread the current VM thread
+ * @param superClass the super class/interface
+ * @param romClass the ROM class of subclass
+ * @param module the subclass's module
+ * @param packageID the subclass's package ID
+ * @return TRUE if subclass can legally inherit the super, FALSE otherwise.
+ */
+static VMINLINE BOOLEAN
+isClassInTheSameModuleOrPckageAsSealedSuper(J9VMThread *vmThread, J9Class *superClass, J9ROMClass *romClass, J9Module *module, UDATA packageID)
+{
+	if (J9ROMCLASS_IS_SEALED(superClass->romClass)) {
+		J9JavaVM *vm = vmThread->javaVM;
+		J9UTF8 *className = J9ROMCLASS_CLASSNAME(romClass);
+		bool classIsPublic = J9_ARE_ALL_BITS_SET(romClass->modifiers, J9AccPublic);
+		J9Module * superModule = superClass->module;
+
+		if (J9_IS_J9MODULE_UNNAMED(vm, superModule)) {
+			if (!classIsPublic && (packageID != superClass->packageID)) {
+				Trc_VM_CreateRAMClassFromROMClass_sealedSuperFromDifferentPackage(vmThread, superClass, J9UTF8_LENGTH(className), J9UTF8_DATA(className));
+				setCurrentExceptionForBadClass(vmThread, className, J9VMCONSTANTPOOL_JAVALANGINCOMPATIBLECLASSCHANGEERROR, J9NLS_VM_CLASS_LOADING_ERROR_SEALED_SUPER_IN_DIFFERENT_PACKAGE);
+				return FALSE;
+			}
+		} else {
+			if (module != superModule) {
+				Trc_VM_CreateRAMClassFromROMClass_sealedSuperFromDifferentModule(vmThread, superClass, J9UTF8_LENGTH(className), J9UTF8_DATA(className));
+				setCurrentExceptionForBadClass(vmThread, className, J9VMCONSTANTPOOL_JAVALANGINCOMPATIBLECLASSCHANGEERROR, J9NLS_VM_CLASS_LOADING_ERROR_SEALED_SUPER_IN_DIFFERENT_MODULE);
+				return FALSE;
+			}
+		}
+	}
+
+	return TRUE;
+}
+#endif /* JAVA_SPEC_VERSION >= 16 */
+
 /**
  * Attempts to recursively load (if necessary) the required superclass and
  * interfaces for the class being loaded.
@@ -1684,6 +1726,15 @@ loadSuperClassAndInterfaces(J9VMThread *vmThread, J9ClassLoader *classLoader, J9
 				return FALSE;
 			}
 
+#if JAVA_SPEC_VERSION >= 16
+			/* JEP 397 sealed classes: the current class must be in the same module as its superclass
+			 * or in the same package as its superclass if non-public.
+			 */
+			if (!isClassInTheSameModuleOrPckageAsSealedSuper(vmThread, superclass, romClass, module, packageID)) {
+				return FALSE;
+			}
+#endif /* JAVA_SPEC_VERSION >= 16 */
+
 			/* JEP 360 sealed classes: if superclass is sealed it must contain the romClass's name in its PermittedSubclasses attribute */
 			if (! isClassPermittedBySealedSuper(superclass->romClass, J9UTF8_DATA(className), J9UTF8_LENGTH(className))) {
 				Trc_VM_CreateRAMClassFromROMClass_classIsNotPermittedBySealedSuperclass(vmThread, superclass, J9UTF8_LENGTH(className), J9UTF8_DATA(className));
@@ -1751,6 +1802,15 @@ loadSuperClassAndInterfaces(J9VMThread *vmThread, J9ClassLoader *classLoader, J9
 						return FALSE;
 					}
 
+#if JAVA_SPEC_VERSION >= 16
+					/* JEP 397 sealed classes: the current interface must be in the same module as its superinterface
+					 * or in the same package as its superinterface if non-public.
+					 */
+					if (!isClassInTheSameModuleOrPckageAsSealedSuper(vmThread, interfaceClass, romClass, module, packageID)) {
+						return FALSE;
+					}
+#endif /* JAVA_SPEC_VERSION >= 16 */
+
 					/* JEP 360 sealed classes: if superinterface is sealed it must contain the romClass's name in its PermittedSubclasses attribute */
 					if (! isClassPermittedBySealedSuper(interfaceClass->romClass, J9UTF8_DATA(className), J9UTF8_LENGTH(className))) {
 						Trc_VM_CreateRAMClassFromROMClass_classIsNotPermittedBySealedSuperinterface(vmThread, interfaceClass, J9UTF8_LENGTH(className), J9UTF8_DATA(className));

runtime/vm/j9vm.tdf

@@ -874,3 +874,6 @@ TraceExit=Trc_VM_resolveInvokeDynamic_Exit Overhead=1 Level=3 Template="resolveI
 TraceEntry=Trc_VM_sendResolveOpenJDKInvokeHandle_Entry Overhead=1 Level=2 Template="sendResolveOpenJDKInvokeHandle"
 TraceExit=Trc_VM_sendResolveOpenJDKInvokeHandle_Exit Overhead=1 Level=2 Template="sendResolveOpenJDKInvokeHandle"
 TraceEntry=Trc_VM_romClassLoadFromCookie_Entry2 Overhead=1 Level=3 Template="romClassLoadFromCookie vmStruct=%p clsNamePtr=%p clsName=%.*s romClassBytes=%p romClassLength=%d"
+
+TraceException=Trc_VM_CreateRAMClassFromROMClass_sealedSuperFromDifferentModule Overhead=1 Level=1 Template="The sealed super class/interface (RAM class=%p) is not in the same module as %.*s"
+TraceException=Trc_VM_CreateRAMClassFromROMClass_sealedSuperFromDifferentPackage Overhead=1 Level=1 Template="The sealed super class/interface (RAM class=%p) is not in the same package as %.*s (non-public)"

test/functional/Java16andUp/build.xml

@@ -35,13 +35,46 @@
 	<!--Properties for this particular build-->
 	<property name="src" location="./src"/>
 	<property name="build" location="./bin"/>
+	<property name="module_src_root" location="./modules"/>
+	<property name="module_bin_root" location="./module_bin"/>
+	<property name="dest_module_bin" location="${DEST}/module_bin"/>
 	<property name="LIB" value="asm,testng,jcommander"/>
 	<import file="${TEST_ROOT}/TKG/scripts/getDependencies.xml"/>
 
 	<target name="init">
 		<mkdir dir="${DEST}" />
 		<mkdir dir="${build}"/>
 	</target>
+
+	<property name="MODULE_NAME_ROOT" value="org.openj9test.modularity" />
+	<property name="MODULE_PATH_ROOT" value="org/openj9/test/modularity"/>
+
+	<target name="compile_modules" depends="init" description="Create the base modules for the sealed classes">
+		<mkdir dir="${module_bin_root}" />
+		<copy file="${LIB_DIR}/testng.jar" todir="${module_bin_root}" />
+		<copy file="${LIB_DIR}/jcommander.jar" todir="${module_bin_root}" />
+		<copy file="${LIB_DIR}/asm.jar" todir="${module_bin_root}" />
+		<for list="moduleX,moduleY" param="mod">
+			<sequential>
+				<var name="module_src_dir" value="${module_src_root}/${MODULE_NAME_ROOT}.@{mod}" />
+				<var name="module_bin_dir" value="${module_bin_root}/${MODULE_NAME_ROOT}.@{mod}" />
+				<mkdir dir="${module_bin_dir}" />
+				<var name="modpath" value="--module-path ${module_bin_root} -d ${module_bin_dir}" />
+				<javac srcdir="${module_src_dir}" destdir="${module_bin_dir}" debug="true" fork="true" executable="${compiler.javac}" includeAntRuntime="false" encoding="ISO-8859-1">
+					<src path="${module_src_dir}" />
+					<compilerarg line='--add-exports java.base/jdk.internal.misc=ALL-UNNAMED' />
+					<compilerarg line='--enable-preview --source ${JDK_VERSION}' />
+					<compilerarg line="${modpath}" />
+					<classpath>
+						<pathelement location="${LIB_DIR}/testng.jar"/>
+						<pathelement location="${LIB_DIR}/jcommander.jar"/>
+						<pathelement location="${LIB_DIR}/asm.jar" />
+						<pathelement location="${build}" />
+					</classpath>
+				</javac>
+			</sequential>
+		</for>
+	</target>
 
 	<target name="compile" depends="init,getDependentLibs" description="Using java ${JDK_VERSION} to compile the source" >
 		<echo>Ant version is ${ant.version}</echo>
@@ -53,6 +86,7 @@
 
 		<javac srcdir="${src}" destdir="${build}" debug="true" fork="true" executable="${compiler.javac}" includeAntRuntime="false" encoding="ISO-8859-1">
 			<src path="${src}"/>
+			<exclude name="**/modules/**" />
 			<compilerarg line='--add-exports java.base/jdk.internal.misc=ALL-UNNAMED' />
 			<compilerarg line='--enable-preview --source ${JDK_VERSION}' />
 			<classpath>
@@ -64,10 +98,16 @@
 		</javac>
 	</target>
 
-	<target name="dist" depends="compile,dist_functional" description="generate the distribution" >
+	<target name="dist" depends="compile,dist_functional,compile_modules" description="generate the distribution" >
+		<echo>copy ${module_bin_root} to ${dest_module_bin}</echo>
+		<mkdir dir="${dest_module_bin}"/>
+		<copy todir="${dest_module_bin}">
+			<fileset dir="${module_bin_root}"/>
+		</copy>
 		<mkdir dir="${DEST}"/>
 		<jar jarfile="${DEST}/GeneralTest.jar" filesonly="true">
 			<fileset dir="${build}"/>
+			<fileset dir="${dest_module_bin}"/>
 			<fileset dir="${src}/../" includes="*.properties,*.xml"/>
 		</jar>
 		<copy todir="${DEST}">

test/functional/Java16andUp/modules/org.openj9test.modularity.moduleX/module-info.java

@@ -0,0 +1,28 @@
+/*******************************************************************************
+ * Copyright (c) 2021, 2021 IBM Corp. and others
+ *
+ * This program and the accompanying materials are made available under
+ * the terms of the Eclipse Public License 2.0 which accompanies this
+ * distribution and is available at https://www.eclipse.org/legal/epl-2.0/
+ * or the Apache License, Version 2.0 which accompanies this distribution and
+ * is available at https://www.apache.org/licenses/LICENSE-2.0.
+ *
+ * This Source Code may also be made available under the following
+ * Secondary Licenses when the conditions for such availability set
+ * forth in the Eclipse Public License, v. 2.0 are satisfied: GNU
+ * General Public License, version 2 with the GNU Classpath
+ * Exception [1] and GNU General Public License, version 2 with the
+ * OpenJDK Assembly Exception [2].
+ *
+ * [1] https://www.gnu.org/software/classpath/license.html
+ * [2] http://openjdk.java.net/legal/assembly-exception.html
+ *
+ * SPDX-License-Identifier: EPL-2.0 OR Apache-2.0 OR GPL-2.0 WITH Classpath-exception-2.0 OR LicenseRef-GPL-2.0 WITH Assembly-exception
+ *******************************************************************************/
+
+module org.openj9test.modularity.moduleX {
+	exports org.openj9.test.modularity.pkgA;
+	exports org.openj9.test.modularity.pkgD;
+	requires testng;
+	requires org.objectweb.asm;
+}

test/functional/Java16andUp/modules/org.openj9test.modularity.moduleX/org/openj9/test/modularity/pkgA/SuperClassSealed.java

@@ -0,0 +1,32 @@
+package org.openj9.test.modularity.pkgA;
+
+/*******************************************************************************
+ * Copyright (c) 2021, 2021 IBM Corp. and others
+ *
+ * This program and the accompanying materials are made available under
+ * the terms of the Eclipse Public License 2.0 which accompanies this
+ * distribution and is available at https://www.eclipse.org/legal/epl-2.0/
+ * or the Apache License, Version 2.0 which accompanies this distribution and
+ * is available at https://www.apache.org/licenses/LICENSE-2.0.
+ *
+ * This Source Code may also be made available under the following
+ * Secondary Licenses when the conditions for such availability set
+ * forth in the Eclipse Public License, v. 2.0 are satisfied: GNU
+ * General Public License, version 2 with the GNU Classpath
+ * Exception [1] and GNU General Public License, version 2 with the
+ * OpenJDK Assembly Exception [2].
+ *
+ * [1] https://www.gnu.org/software/classpath/license.html
+ * [2] http://openjdk.java.net/legal/assembly-exception.html
+ *
+ * SPDX-License-Identifier: EPL-2.0 OR Apache-2.0 OR GPL-2.0 WITH Classpath-exception-2.0 OR LicenseRef-GPL-2.0 WITH Assembly-exception
+ *******************************************************************************/
+
+import org.openj9.test.modularity.pkgD.SubClassPermitted1;
+
+public sealed class SuperClassSealed permits TestSubclass1,SubClassPermitted1 {
+}
+
+/* Only used for the placeholder in the PermittedSubclasses attribute of the sealed superclass */
+non-sealed class TestSubclass1 extends SuperClassSealed {
+}

test/functional/Java16andUp/modules/org.openj9test.modularity.moduleX/org/openj9/test/modularity/pkgA/SuperInterfaceSealed.java

@@ -0,0 +1,32 @@
+package org.openj9.test.modularity.pkgA;
+
+/*******************************************************************************
+ * Copyright (c) 2021, 2021 IBM Corp. and others
+ *
+ * This program and the accompanying materials are made available under
+ * the terms of the Eclipse Public License 2.0 which accompanies this
+ * distribution and is available at https://www.eclipse.org/legal/epl-2.0/
+ * or the Apache License, Version 2.0 which accompanies this distribution and
+ * is available at https://www.apache.org/licenses/LICENSE-2.0.
+ *
+ * This Source Code may also be made available under the following
+ * Secondary Licenses when the conditions for such availability set
+ * forth in the Eclipse Public License, v. 2.0 are satisfied: GNU
+ * General Public License, version 2 with the GNU Classpath
+ * Exception [1] and GNU General Public License, version 2 with the
+ * OpenJDK Assembly Exception [2].
+ *
+ * [1] https://www.gnu.org/software/classpath/license.html
+ * [2] http://openjdk.java.net/legal/assembly-exception.html
+ *
+ * SPDX-License-Identifier: EPL-2.0 OR Apache-2.0 OR GPL-2.0 WITH Classpath-exception-2.0 OR LicenseRef-GPL-2.0 WITH Assembly-exception
+ *******************************************************************************/
+
+import org.openj9.test.modularity.pkgD.SubClassPermitted2;
+
+public sealed interface SuperInterfaceSealed permits TestSubclass2, SubClassPermitted2 {
+}
+
+/* Only used for the placeholder in the PermittedSubclasses attribute of the sealed superinterface */
+non-sealed class TestSubclass2 implements SuperInterfaceSealed {
+}

test/functional/Java16andUp/modules/org.openj9test.modularity.moduleX/org/openj9/test/modularity/pkgD/SubClassPermitted1.java

@@ -0,0 +1,28 @@
+package org.openj9.test.modularity.pkgD;
+
+/*******************************************************************************
+ * Copyright (c) 2021, 2021 IBM Corp. and others
+ *
+ * This program and the accompanying materials are made available under
+ * the terms of the Eclipse Public License 2.0 which accompanies this
+ * distribution and is available at https://www.eclipse.org/legal/epl-2.0/
+ * or the Apache License, Version 2.0 which accompanies this distribution and
+ * is available at https://www.apache.org/licenses/LICENSE-2.0.
+ *
+ * This Source Code may also be made available under the following
+ * Secondary Licenses when the conditions for such availability set
+ * forth in the Eclipse Public License, v. 2.0 are satisfied: GNU
+ * General Public License, version 2 with the GNU Classpath
+ * Exception [1] and GNU General Public License, version 2 with the
+ * OpenJDK Assembly Exception [2].
+ *
+ * [1] https://www.gnu.org/software/classpath/license.html
+ * [2] http://openjdk.java.net/legal/assembly-exception.html
+ *
+ * SPDX-License-Identifier: EPL-2.0 OR Apache-2.0 OR GPL-2.0 WITH Classpath-exception-2.0 OR LicenseRef-GPL-2.0 WITH Assembly-exception
+ *******************************************************************************/
+
+import org.openj9.test.modularity.pkgA.SuperClassSealed;
+
+public non-sealed class SubClassPermitted1 extends SuperClassSealed {
+}

test/functional/Java16andUp/modules/org.openj9test.modularity.moduleX/org/openj9/test/modularity/pkgD/SubClassPermitted2.java

@@ -0,0 +1,29 @@
+package org.openj9.test.modularity.pkgD;
+
+/*******************************************************************************
+ * Copyright (c) 2021, 2021 IBM Corp. and others
+ *
+ * This program and the accompanying materials are made available under
+ * the terms of the Eclipse Public License 2.0 which accompanies this
+ * distribution and is available at https://www.eclipse.org/legal/epl-2.0/
+ * or the Apache License, Version 2.0 which accompanies this distribution and
+ * is available at https://www.apache.org/licenses/LICENSE-2.0.
+ *
+ * This Source Code may also be made available under the following
+ * Secondary Licenses when the conditions for such availability set
+ * forth in the Eclipse Public License, v. 2.0 are satisfied: GNU
+ * General Public License, version 2 with the GNU Classpath
+ * Exception [1] and GNU General Public License, version 2 with the
+ * OpenJDK Assembly Exception [2].
+ *
+ * [1] https://www.gnu.org/software/classpath/license.html
+ * [2] http://openjdk.java.net/legal/assembly-exception.html
+ *
+ * SPDX-License-Identifier: EPL-2.0 OR Apache-2.0 OR GPL-2.0 WITH Classpath-exception-2.0 OR LicenseRef-GPL-2.0 WITH Assembly-exception
+ *******************************************************************************/
+
+import org.openj9.test.modularity.pkgA.SuperInterfaceSealed;
+import org.openj9.test.modularity.pkgD.SuperClassInSamePkg;
+
+public non-sealed class SubClassPermitted2 extends SuperClassInSamePkg implements SuperInterfaceSealed {
+}

test/functional/Java16andUp/modules/org.openj9test.modularity.moduleX/org/openj9/test/modularity/pkgD/SuperClassInSamePkg.java

@@ -0,0 +1,25 @@
+package org.openj9.test.modularity.pkgD;
+
+/*******************************************************************************
+ * Copyright (c) 2021, 2021 IBM Corp. and others
+ *
+ * This program and the accompanying materials are made available under
+ * the terms of the Eclipse Public License 2.0 which accompanies this
+ * distribution and is available at https://www.eclipse.org/legal/epl-2.0/
+ * or the Apache License, Version 2.0 which accompanies this distribution and
+ * is available at https://www.apache.org/licenses/LICENSE-2.0.
+ *
+ * This Source Code may also be made available under the following
+ * Secondary Licenses when the conditions for such availability set
+ * forth in the Eclipse Public License, v. 2.0 are satisfied: GNU
+ * General Public License, version 2 with the GNU Classpath
+ * Exception [1] and GNU General Public License, version 2 with the
+ * OpenJDK Assembly Exception [2].
+ *
+ * [1] https://www.gnu.org/software/classpath/license.html
+ * [2] http://openjdk.java.net/legal/assembly-exception.html
+ *
+ * SPDX-License-Identifier: EPL-2.0 OR Apache-2.0 OR GPL-2.0 WITH Classpath-exception-2.0 OR LicenseRef-GPL-2.0 WITH Assembly-exception
+ *******************************************************************************/
+
+public class SuperClassInSamePkg {}