src/java.base/share/classes/java/lang/invoke/MethodHandleImpl.java

rev 58565 : 8238358: Implementation of JEP 371: Hidden Classes
Reviewed-by: duke
Contributed-by: mandy.chung@oracle.com, lois.foltan@oracle.com, david.holmes@oracle.com, harold.seigel@oracle.com, serguei.spitsyn@oracle.com, alex.buckley@oracle.com, jamsheed.c.m@oracle.com

@@ -25,11 +25,10 @@
 
 package java.lang.invoke;
 
 import jdk.internal.access.JavaLangInvokeAccess;
 import jdk.internal.access.SharedSecrets;
-import jdk.internal.org.objectweb.asm.AnnotationVisitor;
 import jdk.internal.org.objectweb.asm.ClassWriter;
 import jdk.internal.org.objectweb.asm.MethodVisitor;
 import jdk.internal.reflect.CallerSensitive;
 import jdk.internal.reflect.Reflection;
 import jdk.internal.vm.annotation.ForceInline;

@@ -38,10 +37,11 @@
 import sun.invoke.empty.Empty;
 import sun.invoke.util.ValueConversions;
 import sun.invoke.util.VerifyType;
 import sun.invoke.util.Wrapper;
 
+import java.lang.invoke.MethodHandles.Lookup;
 import java.lang.reflect.Array;
 import java.nio.ByteOrder;
 import java.util.Arrays;
 import java.util.Collections;
 import java.util.HashMap;

@@ -1155,14 +1155,28 @@
             // Cache the result of makeInjectedInvoker once per argument class.
             MethodHandle bccInvoker = CV_makeInjectedInvoker.get(hostClass);
             return restoreToType(bccInvoker.bindTo(vamh), mh, hostClass);
         }
 
-        private static MethodHandle makeInjectedInvoker(Class<?> hostClass) {
+        private static MethodHandle makeInjectedInvoker(Class<?> targetClass) {
             try {
-                Class<?> invokerClass = UNSAFE.defineAnonymousClass(hostClass, INJECTED_INVOKER_TEMPLATE, null);
-                assert checkInjectedInvoker(hostClass, invokerClass);
+                /*
+                 * The invoker class defined to the same class loader as the lookup class
+                 * but in an unnamed package so that the class bytes can be cached and
+                 * reused for any @CSM.
+                 *
+                 * @CSM must be public and exported if called by any module.
+                 */
+                String name = targetClass.getName() + "$$InjectedInvoker";
+                if (targetClass.isHiddenClass()) {
+                    // use the original class name
+                    name = name.replace('/', '_');
+                }
+                Class<?> invokerClass = new Lookup(targetClass)
+                        .makeHiddenClassDefiner(name, INJECTED_INVOKER_TEMPLATE)
+                        .defineClass(true);
+                assert checkInjectedInvoker(targetClass, invokerClass);
                 return IMPL_LOOKUP.findStatic(invokerClass, "invoke_V", INVOKER_MT);
             } catch (ReflectiveOperationException ex) {
                 throw uncaughtException(ex);
             }
         }

@@ -1254,14 +1268,10 @@
 
             MethodVisitor mv = cw.visitMethod(ACC_STATIC, "invoke_V",
                           "(Ljava/lang/invoke/MethodHandle;[Ljava/lang/Object;)Ljava/lang/Object;",
                           null, null);
 
-            // Suppress invoker method in stack traces.
-            AnnotationVisitor av0 = mv.visitAnnotation(InvokerBytecodeGenerator.HIDDEN_SIG, true);
-            av0.visitEnd();
-
             mv.visitCode();
             mv.visitVarInsn(ALOAD, 0);
             mv.visitVarInsn(ALOAD, 1);
             mv.visitMethodInsn(INVOKEVIRTUAL, "java/lang/invoke/MethodHandle", "invokeExact",
                                "([Ljava/lang/Object;)Ljava/lang/Object;", false);