From 5745bfd08b878deffd15f7c927ed0b237cb92e13 Mon Sep 17 00:00:00 2001
From: liach <liach@openjdk.org>
Date: Tue, 25 Feb 2025 16:17:32 -0600
Subject: [PATCH] Improve BytecodeDescriptor error message

---
 .../sun/invoke/util/BytecodeDescriptor.java       | 10 +++++++++-
 .../share/classes/sun/invoke/util/Wrapper.java    | 15 ++++++++++++++-
 .../lang/annotation/MalformedAnnotationTest.java  |  4 ++--
 3 files changed, 25 insertions(+), 4 deletions(-)

diff --git a/src/java.base/share/classes/sun/invoke/util/BytecodeDescriptor.java b/src/java.base/share/classes/sun/invoke/util/BytecodeDescriptor.java
index 0f36ba48d33..bf842bf33d7 100644
--- a/src/java.base/share/classes/sun/invoke/util/BytecodeDescriptor.java
+++ b/src/java.base/share/classes/sun/invoke/util/BytecodeDescriptor.java
@@ -95,6 +95,13 @@ public class BytecodeDescriptor {
     }
 
     /**
+     * Parse a single type in a descriptor. Results can be:
+     * <ul>
+     *     <li>A {@code Class} for successful parsing
+     *     <li>{@code null} for malformed descriptor format
+     *     <li>Throwing a {@link TypeNotPresentException} for valid class name,
+     *     but class cannot be discovered
+     * </ul>
      * @param loader the class loader in which to look up the types (null means
      *               bootstrap class loader)
      */
@@ -117,7 +124,8 @@ public class BytecodeDescriptor {
                 t = t.arrayType();
             return t;
         } else {
-            return Wrapper.forBasicType(c).primitiveType();
+            var w = Wrapper.forPrimitiveTypeOrNull(c);
+            return w == null ? null : w.primitiveType();
         }
     }
 
diff --git a/src/java.base/share/classes/sun/invoke/util/Wrapper.java b/src/java.base/share/classes/sun/invoke/util/Wrapper.java
index 4e8beaabb34..361b35abfd8 100644
--- a/src/java.base/share/classes/sun/invoke/util/Wrapper.java
+++ b/src/java.base/share/classes/sun/invoke/util/Wrapper.java
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2008, 2024, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2008, 2025, 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
@@ -352,6 +352,19 @@ public enum Wrapper {
         throw basicTypeError(type);
     }
 
+    /**
+     * Return the primitive wrapper for the given char.  Does not return
+     * {@code OBJECT}. Returns {@code null} to allow flexible error messages.
+     * Dedicated for {@link BytecodeDescriptor}.
+     */
+    static Wrapper forPrimitiveTypeOrNull(char type) {
+        Wrapper w = FROM_CHAR[(type + (type >> 1)) & 0xf];
+        if (w != null && w != OBJECT && w.basicTypeChar == type) {
+            return w;
+        }
+        return null;
+    }
+
     @DontInline
     private static RuntimeException basicTypeError(char type) {
         for (Wrapper x : values()) {
diff --git a/test/jdk/java/lang/annotation/MalformedAnnotationTest.java b/test/jdk/java/lang/annotation/MalformedAnnotationTest.java
index 1276cb774ac..7047c125688 100644
--- a/test/jdk/java/lang/annotation/MalformedAnnotationTest.java
+++ b/test/jdk/java/lang/annotation/MalformedAnnotationTest.java
@@ -67,8 +67,8 @@ class MalformedAnnotationTest {
                                 AnnotationElement.of("value", AnnotationValue.ofClass(clb
                                         .constantPool().utf8Entry(badDescString))))
                 )));
-        var cl = ByteCodeLoader.load("Test", bytes);
+        var cl = new ByteCodeLoader("Test", bytes, MalformedAnnotationTest.class.getClassLoader()).loadClass("Test");
         var ex = assertThrows(GenericSignatureFormatError.class, () -> cl.getDeclaredAnnotation(ClassCarrier.class));
-        assertTrue(ex.getMessage().contains(badDescString));
+        assertTrue(ex.getMessage().contains(badDescString), () -> "Uninformative error: " + ex);
     }
 }