8055063: Parameter#toString() fails w/ AIOOBE for ctr of inner class w/ generic type

Add getAllGenericParameters, which attempts to report generic parameters with synthetic parameters to the best extent possible with current classfile information.

Reviewed-by: jfranck

jdk/src/java.base/share/classes/java/lang/reflect/Executable.java

@@ -285,6 +285,53 @@ public abstract class Executable extends AccessibleObject
             return getParameterTypes();
     }
 
+    /**
+     * Behaves like {@code getGenericParameterTypes}, but returns type
+     * information for all parameters, including synthetic parameters.
+     */
+    Type[] getAllGenericParameterTypes() {
+        final boolean genericInfo = hasGenericInformation();
+
+        // Easy case: we don't have generic parameter information.  In
+        // this case, we just return the result of
+        // getParameterTypes().
+        if (!genericInfo) {
+            return getParameterTypes();
+        } else {
+            final boolean realParamData = hasRealParameterData();
+            final Type[] genericParamTypes = getGenericParameterTypes();
+            final Type[] nonGenericParamTypes = getParameterTypes();
+            final Type[] out = new Type[nonGenericParamTypes.length];
+            final Parameter[] params = getParameters();
+            int fromidx = 0;
+            // If we have real parameter data, then we use the
+            // synthetic and mandate flags to our advantage.
+            if (realParamData) {
+                for (int i = 0; i < out.length; i++) {
+                    final Parameter param = params[i];
+                    if (param.isSynthetic() || param.isImplicit()) {
+                        // If we hit a synthetic or mandated parameter,
+                        // use the non generic parameter info.
+                        out[i] = nonGenericParamTypes[i];
+                    } else {
+                        // Otherwise, use the generic parameter info.
+                        out[i] = genericParamTypes[fromidx];
+                        fromidx++;
+                    }
+                }
+            } else {
+                // Otherwise, use the non-generic parameter data.
+                // Without method parameter reflection data, we have
+                // no way to figure out which parameters are
+                // synthetic/mandated, thus, no way to match up the
+                // indexes.
+                return genericParamTypes.length == nonGenericParamTypes.length ?
+                    genericParamTypes : nonGenericParamTypes;
+            }
+            return out;
+        }
+    }
+
     /**
      * Returns an array of {@code Parameter} objects that represent
      * all the parameters to the underlying executable represented by
@@ -646,7 +693,7 @@ public abstract class Executable extends AccessibleObject
                         getConstantPool(getDeclaringClass()),
                 this,
                 getDeclaringClass(),
-                getGenericParameterTypes(),
+                getAllGenericParameterTypes(),
                 TypeAnnotation.TypeAnnotationTarget.METHOD_FORMAL_PARAMETER);
     }
 

jdk/src/java.base/share/classes/java/lang/reflect/Parameter.java

@@ -198,7 +198,7 @@ public final class Parameter implements AnnotatedElement {
     public Type getParameterizedType() {
         Type tmp = parameterTypeCache;
         if (null == tmp) {
-            tmp = executable.getGenericParameterTypes()[index];
+            tmp = executable.getAllGenericParameterTypes()[index];
             parameterTypeCache = tmp;
         }
 

jdk/test/java/lang/reflect/Parameter/InnerClassToString.java

@@ -0,0 +1,95 @@
+/*
+ * Copyright (c) 2014, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+/*
+ * @test
+ * @bug 8055063
+ * @summary javac should generate method parameters correctly.
+ * @clean InnerClassToString
+ * @compile -parameters InnerClassToString.java
+ * @run main InnerClassToString
+ * @clean InnerClassToString
+ * @compile InnerClassToString.java
+ * @run main InnerClassToString
+ */
+
+import java.lang.reflect.Constructor;
+import java.lang.reflect.Parameter;
+import java.util.Set;
+
+// Test copied and expanded from webbug group report.
+public class InnerClassToString {
+    private static final Class<?>[] genericParamClasses = new Class<?>[] {
+        InnerClassToString.class, Set.class
+    };
+
+    private static final Class<?>[] nongenericParamClasses = new Class<?>[] {
+        InnerClassToString.class, String.class
+    };
+
+    private int errors = 0;
+
+    private void test(Constructor<MyEntity> constructor,
+                     Class<?>[] paramClasses) {
+        final Parameter[] params = constructor.getParameters();
+
+        for (int i = 0; i < params.length; i++) {
+            final Parameter parameter = params[i];
+            System.out.println(parameter.toString());
+
+            if (!parameter.getType().equals(paramClasses[i])) {
+                errors++;
+                System.err.println("Expected type " + paramClasses[i] +
+                                   " but got " + parameter.getType());
+            }
+
+            System.out.println(parameter.getParameterizedType());
+            System.out.println(parameter.getAnnotatedType());
+        }
+
+    }
+
+    private void run() throws Exception {
+        final Constructor<MyEntity> genericConstructor =
+            MyEntity.class.getConstructor(InnerClassToString.class, Set.class);
+
+        test(genericConstructor, genericParamClasses);
+
+        final Constructor<MyEntity> nongenericConstructor =
+            MyEntity.class.getConstructor(InnerClassToString.class, String.class);
+
+        test(nongenericConstructor, nongenericParamClasses);
+
+        if (errors != 0)
+            throw new RuntimeException(errors + " errors in test");
+    }
+
+    public static void main(String[] args) throws Exception {
+        new InnerClassToString().run();
+    }
+
+    public class MyEntity {
+        public MyEntity(Set<?> names) {}
+        public MyEntity(String names) {}
+    }
+}