Merge pull request #10520 from hangshao0/v0.22.0

(v0.22.0) Hidden class implementation 4

jcl/src/java.base/share/classes/java/lang/Class.java

@@ -3428,8 +3428,12 @@ public String getSimpleName() {
 	String simpleName = baseType.getSimpleNameImpl();
 	String fullName = baseType.getName();
 	if (simpleName == null) {
-		Class<?> parent = baseType.getEnclosingObjectClass();
-		// either a base class, or anonymous class
+		/** 
+		 * It is a base class, an anonymous class, or a hidden class.
+		 * Call getEnclosingClass() instead of getEnclosingObjectClass() to check getDeclaringClass() first. Hidden class test expects
+		 * NoClassDefFoundError from getDeclaringClass(). 
+		 */
+		Class<?> parent = baseType.getEnclosingClass();
 		if (parent != null) {
 			simpleName = ""; //$NON-NLS-1$
 		} else {
@@ -3493,12 +3497,6 @@ else if (!fullName.endsWith(simpleName)) {
  * @see #isLocalClass()
  */
 public String getCanonicalName() {
-/*[IF Java15]*/
-	if (isHidden()) {
-		/* Canonical name is always null for hidden classes. */
-		return null;
-	}
-/*[ENDIF] Java15 */
 	int arrayCount = 0;
 	Class<?> baseType = this;
 	if (isArray()) {
@@ -3507,6 +3505,12 @@ public String getCanonicalName() {
 			arrayCount++;
 		}
 	}
+/*[IF Java15]*/
+	if (baseType.isHidden()) {
+		/* Canonical name is always null for hidden classes. */
+		return null;
+	}
+/*[ENDIF] Java15 */
 	if (baseType.getEnclosingObjectClass() != null) {
 		// local or anonymous class
 		return null;
@@ -4665,6 +4669,20 @@ public Class<?> componentType() {
 	 * @return Optional with a nominal descriptor of Class instance
 	 */
 	public Optional<ClassDesc> describeConstable() {
+/*[IF Java15]*/
+		Class<?> clazz = this;
+		if (isArray()) {
+			clazz = getComponentType();
+			while (clazz.isArray()) {
+				clazz = clazz.getComponentType();
+			}
+		}
+		if (clazz.isHidden()) {
+			/* It is always an empty Optional for hidden classes. */
+			return Optional.empty(); 
+		}
+/*[ENDIF] Java15 */		
+
 		ClassDesc classDescriptor = ClassDesc.ofDescriptor(this.descriptorString());
 		return Optional.of(classDescriptor);
 	}
@@ -4699,6 +4717,20 @@ public String descriptorString() {
 			}
 		}
 		String name = this.getName().replace('.', '/');
+/*[IF Java15]*/
+		Class<?> clazz = this;
+		if (isArray()) {
+			clazz = getComponentType();
+			while (clazz.isArray()) {
+				clazz = clazz.getComponentType();
+			}
+		}
+		if (clazz.isHidden()) {
+			/* descriptor String of hidden class is something like: "Lpackage/ClassName.romaddress;". */
+			int index = name.lastIndexOf('/');
+			name = name.substring(0, index)+ '.' + name.substring(index + 1,name.length());
+		}
+/*[ENDIF] Java15 */
 		if (this.isArray()) {
 			return name;
 		}

jcl/src/java.base/share/classes/java/lang/invoke/MethodHandleNatives.java

@@ -86,6 +86,8 @@ static boolean refKindIsConstructor(byte kind) {
 	static Object classData(Class<?> c) {
 		return JLA.classData(c);
 	}
+
+	native static void checkClassBytes(byte[] bytes);
 	/*[ENDIF] Java15 */
 }
 /*[ENDIF] Java11 */

jcl/src/java.base/share/classes/java/lang/invoke/MethodHandles.java

@@ -51,6 +51,7 @@
 import java.util.AbstractList;
 import java.util.Iterator;
 import java.util.ArrayList;
+import java.nio.ByteBuffer;
 import java.nio.ByteOrder;
 import jdk.internal.reflect.CallerSensitive;
 import java.lang.invoke.VarHandle.AccessMode;
@@ -67,6 +68,8 @@
 /*[ENDIF] Java12 */
 import java.security.ProtectionDomain;
 import jdk.internal.org.objectweb.asm.ClassReader;
+import jdk.internal.org.objectweb.asm.Opcodes;
+import jdk.internal.org.objectweb.asm.Type;
 /*[ELSE] Sidecar19-SE-OpenJ9
 import java.lang.reflect.Module;
 /*[ENDIF] Sidecar19-SE-OpenJ9*/
@@ -1765,7 +1768,13 @@ public MethodHandle unreflectSetter(Field field) throws IllegalAccessException {
 			/* https://github.com/eclipse/openj9/issues/3175
 			 * Setters are allowed on instance final instance fields if they have been set accessible.
 			 */
-			if (Modifier.isFinal(modifiers) && (!field.isAccessible() || Modifier.isStatic(modifiers))) {
+			if (Modifier.isFinal(modifiers) && 
+				(!field.isAccessible() || Modifier.isStatic(modifiers)
+			/*[IF Java15]
+				|| declaringClass.isHidden()
+			/*[ENDIF] Java15 */
+				)
+			) {
 				/*[MSG "K05cf", "illegal setter on final field"]*/
 				throw new IllegalAccessException(Msg.getString("K05cf")); //$NON-NLS-1$
 			}
@@ -2368,21 +2377,58 @@ private ClassDefiner classDefiner(byte[] bytes, ClassOption... classOptions) thr
 				throw new IllegalAccessException();
 			}
 
+			int flags = 0;
+			for (ClassOption opt : classOptions) {
+				flags |= opt.toFlag();
+			}
+			MethodHandleNatives.checkClassBytes(bytes);
+			String targetClassName = getClassName(bytes);
+			return makeHiddenClassDefiner(targetClassName, bytes, flags);
+
+		}
+
+		private String getClassName(byte[] bytes) {
+			String targetClassName;
 			ClassReader cr;
 			try {
 				cr = new ClassReader(bytes);
+
+				int thisClassIndex = cr.readUnsignedShort(cr.header + 2);
+				char[] buffer = new char[cr.getMaxStringLength()];
+				Object thisClass = cr.readConst(thisClassIndex, buffer);
+				if (!(thisClass instanceof Type)) {
+					throw new ClassFormatError();
+				}
+				Type type = (Type)thisClass;
+				if (!type.getDescriptor().startsWith("L")) {
+					throw new ClassFormatError();
+				}
+				targetClassName = type.getClassName();
 			} catch (ArrayIndexOutOfBoundsException e) {
 				/*[MSG "K065Y2", "The class byte array is corrupted"]*/
 				throw new ClassFormatError(com.ibm.oti.util.Msg.getString("K065Y2")); //$NON-NLS-1$
+			} catch (RuntimeException e) {
+				ClassFormatError error = new ClassFormatError();
+				error.initCause(e);
+				throw error;
 			}
 
-			String targetClassName = cr.getClassName().replace('/', '.');
-			int flags = 0;
-			for (ClassOption opt : classOptions) {
-				flags |= opt.toFlag();
+			int accessFlag = cr.getAccess();
+			if (Opcodes.ACC_MODULE == (accessFlag & Opcodes.ACC_MODULE)) {
+				/* Must be a class or interface, ACC_MODULE cannot be there. */
+				throw new IllegalArgumentException();
 			}
-
-			return makeHiddenClassDefiner(targetClassName, bytes, flags);
+
+			String pkgName = lookupClass().getPackageName();
+			int index = targetClassName.lastIndexOf('.');
+			String pkgName1 = "";
+			if (0 < index) {
+				pkgName1 = targetClassName.substring(0, index);
+			}
+			if (!pkgName1.equals(pkgName)) {
+				throw new IllegalArgumentException();
+			}
+			return targetClassName;
 		}
 
 		ClassDefiner makeHiddenClassDefiner(String name, byte[] template) {

jcl/src/java.base/share/classes/java/lang/invoke/MethodType.java

@@ -1150,6 +1150,7 @@ static Class<?> unwrapPrimitive(Class<?> wrapperClass){
 		return wrapperClass;
 	}
 
+	/* The string returned by this method should be in sync with Class.descriptorString() */
 	static String getBytecodeStringName(Class<?> c){
 		if (c.isPrimitive()) {
 			if (c == int.class) {
@@ -1172,7 +1173,22 @@ static String getBytecodeStringName(Class<?> c){
 				return "S"; //$NON-NLS-1$
 			}
 		}
+		Class<?> clazz = c;
+		if (c.isArray()) {
+			clazz = c.getComponentType();
+			while (clazz.isArray()) {
+				clazz = clazz.getComponentType();
+			}
+		}
 		String name = c.getName().replace('.', '/');
+		/*[IF Java15]*/
+		if (clazz.isHidden()) {
+			/* keep the last "." before romaddress for hidden classes */
+			int index = name.lastIndexOf('/');
+			name = name.substring(0, index) + '.' + name.substring(index + 1,name.length());
+		}
+		/*[ENDIF] Java15 */
+
 		if (c.isArray()) {
 			return name;
 		}

runtime/bcutil/BuildResult.hpp

@@ -1,5 +1,5 @@
 /*******************************************************************************
- * Copyright (c) 2001, 2019 IBM Corp. and others
+ * Copyright (c) 2001, 2020 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
@@ -48,6 +48,7 @@ enum BuildResult {
 	InvalidAnnotation = BCT_ERR_INVALID_ANNOTATION,
 	LineNumberTableDecompressFailed = BCT_ERR_LINE_NUMBER_TABLE_DECOMPRESS_FAILED,
 	InvalidBytecodeSize = BCT_ERR_INVALID_BYTECODE_SIZE,
+	InvalidClassType = BCT_ERR_INVALID_CLASS_TYPE,
 };
 
 #endif /* BUILDRESULT_HPP_ */

runtime/bcutil/ClassFileOracle.cpp

@@ -227,6 +227,11 @@ ClassFileOracle::ClassFileOracle(BufferManager *bufferManager, J9CfrClassFile *c
 	if (OK == _buildResult) {
 		walkAttributes();
 	}
+
+	if (_context->isClassHidden()) {
+		checkHiddenClass();
+	}
+
 	if (OK == _buildResult) {
 		walkInterfaces();
 	}
@@ -511,21 +516,28 @@ ClassFileOracle::walkAttributes()
 		}
 #if JAVA_SPEC_VERSION >= 11
 		case CFR_ATTRIBUTE_NestMembers:
-			_nestMembers = (J9CfrAttributeNestMembers *)attrib;
-			_nestMembersCount = _nestMembers->numberOfClasses;
-			/* The classRefs are never resolved & therefore do not need to
-			 * be kept in the constant pool.
-			 */
-			for (U_16 i = 0; i < _nestMembersCount; i++) {
-				U_16 classNameIndex = UTF8_INDEX_FROM_CLASS_INDEX(_classFile->constantPool, _nestMembers->classes[i]);
-				markConstantUTF8AsReferenced(classNameIndex);
+			/* ignore CFR_ATTRIBUTE_NestMembers for hidden classes, as the nest members never know the name of hidden classes */
+			if (!_context->isClassHidden()) {
+				_nestMembers = (J9CfrAttributeNestMembers *)attrib;
+				_nestMembersCount = _nestMembers->numberOfClasses;
+				/* The classRefs are never resolved & therefore do not need to
+				 * be kept in the constant pool.
+				 */
+				for (U_16 i = 0; i < _nestMembersCount; i++) {
+					U_16 classNameIndex = UTF8_INDEX_FROM_CLASS_INDEX(_classFile->constantPool, _nestMembers->classes[i]);
+					markConstantUTF8AsReferenced(classNameIndex);
+				}
 			}
 			break;
 
 		case CFR_ATTRIBUTE_NestHost: {
-			U_16 hostClassIndex = ((J9CfrAttributeNestHost *)attrib)->hostClassIndex;
-			_nestHost = UTF8_INDEX_FROM_CLASS_INDEX(_classFile->constantPool, hostClassIndex);
-			markConstantUTF8AsReferenced(_nestHost);
+			/* Ignore CFR_ATTRIBUTE_NestHost for hidden classes, as the nest host of a hidden class is not decided by CFR_ATTRIBUTE_NestHost.
+			 * The nesthost of a hidden class is its host class if ClassOption.NESTMATE is used or itself if ClassOption.NESTMATE is not used. */
+			if (!_context->isClassHidden()) {
+				U_16 hostClassIndex = ((J9CfrAttributeNestHost *)attrib)->hostClassIndex;
+				_nestHost = UTF8_INDEX_FROM_CLASS_INDEX(_classFile->constantPool, hostClassIndex);
+				markConstantUTF8AsReferenced(_nestHost);
+			}
 			break;
 		}
 #endif /* JAVA_SPEC_VERSION >= 11 */
@@ -544,6 +556,38 @@ ClassFileOracle::walkAttributes()
 	}
 }
 
+void
+ClassFileOracle::checkHiddenClass()
+{
+	ROMClassVerbosePhase v(_context, ClassFileAttributesAnalysis);
+	/* Hidden Class cannot be a record or enum. */
+	U_16 superClassNameIndex = getSuperClassNameIndex();
+	bool isEnum = false;
+
+	/**
+	 * See test case jdk/java/lang/invoke/defineHiddenClass/BasicTest.emptyHiddenClass().
+	 * A normal Enum cannot be defined as a hidden class. But an empty enum class that does not
+	 * define constants of its type can still be defined as a hidden class. 
+	 * So when setting isEnum, add a check for field count. 
+	 */
+	if (0 != superClassNameIndex) {
+		isEnum = J9_ARE_ALL_BITS_SET(_classFile->accessFlags, CFR_ACC_ENUM) && 
+				J9UTF8_DATA_EQUALS(getUTF8Data(superClassNameIndex), getUTF8Length(superClassNameIndex), "java/lang/Enum", LITERAL_STRLEN("java/lang/Enum")) &&
+				(getFieldsCount() > 0);
+	}
+	if (_isRecord  || isEnum) {
+		PORT_ACCESS_FROM_PORT(_context->portLibrary());
+		char msg[] = "Hidden Class cannot be a record or enum";
+		UDATA len = sizeof(msg);
+		char *error = (char *) j9mem_allocate_memory(len, J9MEM_CATEGORY_CLASSES);
+		if (NULL != error) {
+			strcpy(error, msg);
+			_context->recordCFRError((U_8*)error);
+		}
+		_buildResult = InvalidClassType;
+	}
+}
+
 void
 ClassFileOracle::walkRecordComponents(J9CfrAttributeRecord *attrib)
 {
@@ -1320,9 +1364,9 @@ ClassFileOracle::walkMethodCodeAttributeAttributes(U_16 methodIndex)
 	/* Verify that each LVTT entry has a matching local variable. Since there is no guaranteed order
 	 * for code attributes, this check must be performed after all attributes are processed.
 	 * 
-	 * According to the JVM spec: ”Each entry in the local_variable_type_table array ... 
+	 * According to the JVM spec: "Each entry in the local_variable_type_table array ... 
 	 * indicates the index into the local variable array of the current frame at which 
-	 * that local variable can be found.”
+	 * that local variable can be found."
 	 * 
 	 * While multiple LocalVariableTypeTable attributes may exist according to the spec, upon observation 
 	 * it is the common case for 'javac' to generate only one attribute per method. To take advantage of this 

runtime/bcutil/ClassFileOracle.hpp

@@ -1084,6 +1084,7 @@ class RecordComponentIterator
 	void walkHeader();
 	void walkFields();
 	void walkAttributes();
+	void checkHiddenClass();
 	void walkInterfaces();
 	void walkMethods();
 	void walkRecordComponents(J9CfrAttributeRecord *attrib);

runtime/bcutil/ROMClassCreationContext.cpp

@@ -157,6 +157,7 @@ ROMClassCreationContext::buildResultString(BuildResult result)
 	case UnknownAnnotation: return "UnknownAnnotation";
 	case ClassNameMismatch: return "ClassNameMismatch";
 	case InvalidAnnotation: return "InvalidAnnotation";
+	case InvalidClassType: return "InvalidClassType";
 	default: return "Unknown";
 	}
 }

runtime/bcutil/cfreader.c

@@ -2731,6 +2731,11 @@ j9bcutil_readClassFileBytes(J9PortLibrary *portLib,
 		return -1;
 	}
 
+	if (J9_ARE_ANY_BITS_SET(flags, BCT_BasicCheckOnly)) {
+		Trc_BCU_j9bcutil_readClassFileBytes_Basic_Check_Exit(0);
+		return 0;
+	}
+
 	if (J9_ARE_ANY_BITS_SET(findClassFlags, J9_FINDCLASS_FLAG_UNSAFE)) {
 		flags |= BCT_Unsafe;
 	}
@@ -3631,3 +3636,18 @@ sortMethodIndex(J9CfrConstantPoolInfo* constantPool, J9CfrMethod *list, IDATA st
 		}
 	}
 }
+
+#if JAVA_SPEC_VERSION >= 15
+I_32
+checkClassBytes(J9VMThread *currentThread, U_8* classBytes, UDATA classBytesLength, U_8* segment, U_32 segmentLength) 
+{
+	I_32 rc = 0;
+	U_32 cfrFlags = BCT_JavaMaxMajorVersionShifted | BCT_AnyPreviewVersion | BCT_BasicCheckOnly;
+	PORT_ACCESS_FROM_VMC(currentThread);
+	if (NULL != classBytes) {
+		rc = j9bcutil_readClassFileBytes(PORTLIB, NULL, classBytes, classBytesLength, segment, segmentLength, cfrFlags, NULL, NULL, 0, 0);
+	}
+	return rc;
+}
+#endif /* JAVA_SPEC_VERSION >= 15 */
+

runtime/bcutil/defineclass.c

@@ -895,6 +895,7 @@ createROMClassFromClassFile(J9VMThread *currentThread, J9LoadROMClassData *loadD
 		 * Error messages are contents of vm->dynamicLoadBuffers->classFileError if anything is assigned
 		 * otherwise just the classname.
 		 */
+		case BCT_ERR_INVALID_CLASS_TYPE:
 		case BCT_ERR_CLASS_NAME_MISMATCH:
 			exceptionNumber = J9VMCONSTANTPOOL_JAVALANGNOCLASSDEFFOUNDERROR;
 			/* FALLTHROUGH */