For some virtual method handles, MethodHandleInfo reports their reference kind incorrectly. The following program (runnable TestNG test case) produces a classfile which does an LDC on "invokevirtual String.toUpperCase", but it is reported as being an invokespecial MH instead.

@Test
public class GenBadMHTest {
    public void testMHForStringToUpper() throws IOException, ReflectiveOperationException {
        ClassWriter cw = new ClassWriter(ClassWriter.COMPUTE_MAXS | ClassWriter.COMPUTE_FRAMES);
        cw.visit(51, ACC_SUPER + ACC_PUBLIC, "Foo", null, "java/lang/Object", new String[0]);

        // Constructor
        MethodVisitor ctor = cw.visitMethod(ACC_PUBLIC, "<init>", "()V", null, null);
        ctor.visitCode();
        ctor.visitVarInsn(ALOAD, 0);
        ctor.visitMethodInsn(INVOKESPECIAL, "java/lang/Object", "<init>", "()V");
        ctor.visitInsn(RETURN);
        ctor.visitMaxs(-1, -1);
        ctor.visitEnd();

        MethodVisitor mv = cw.visitMethod(ACC_PUBLIC, "foo", "()Ljava/lang/Object;", null, null);
        mv.visitLdcInsn(new Handle(Opcodes.H_INVOKEVIRTUAL, "java/lang/String", "toUpperCase", "()Ljava/lang/String;"));
        mv.visitInsn(ARETURN);
        mv.visitMaxs(-1, -1);
        mv.visitEnd();

        cw.visitEnd();

        byte[] bytes = cw.toByteArray();
        File f = new File("Foo.class");
        try (FileOutputStream fos = new FileOutputStream(f)) {
            fos.write(bytes);
        }

        List<URL> list = new ArrayList<>();
        System.out.println(f.getCanonicalFile().getParent());
        list.add(new URL("file:" + f.getCanonicalFile().getParent().toString().replace("\\", "/") + "/"));
        Class clazz = Class.forName("Foo", true, new URLClassLoader(list.toArray(new URL[list.size()])));
        Method m = clazz.getMethod("foo");
        MethodHandle mh = (MethodHandle) m.invoke(clazz.newInstance());
        MethodHandleInfo mhi = new MethodHandleInfo(mh);
        assertTrue(mhi.getReferenceKind() == MethodHandleInfo.REF_invokeVirtual);
    }
}


Javap listing of generated class:

brian:test-ng$ javap -c -v Foo
Classfile /home/brian/work/lambda/lambda/jdk/test-ng/Foo.class
  Last modified Dec 17, 2012; size 249 bytes
  MD5 checksum bec790a14e97276bf262412294213fea
public class Foo
  minor version: 0
  major version: 51
  flags: ACC_PUBLIC, ACC_SUPER
Constant pool:
   #1 = Utf8 Foo
   #2 = Class #1 // Foo
   #3 = Utf8 java/lang/Object
   #4 = Class #3 // java/lang/Object
   #5 = Utf8 <init>
   #6 = Utf8 ()V
   #7 = NameAndType #5:#6 // "<init>":()V
   #8 = Methodref #4.#7 // java/lang/Object."<init>":()V
   #9 = Utf8 foo
  #10 = Utf8 ()Ljava/lang/Object;
  #11 = Utf8 java/lang/String
  #12 = Class #11 // java/lang/String
  #13 = Utf8 toUpperCase
  #14 = Utf8 ()Ljava/lang/String;
  #15 = NameAndType #13:#14 // toUpperCase:()Ljava/lang/String;
  #16 = Methodref #12.#15 // java/lang/String.toUpperCase:()Ljava/lang/String;
  #17 = MethodHandle #5:#16 // invokevirtual java/lang/String.toUpperCase:()Ljava/lang/String;
  #18 = Utf8 Code
{
  public Foo();
    flags: ACC_PUBLIC
    Code:
      stack=1, locals=1, args_size=1
         0: aload_0
         1: invokespecial #8 // Method java/lang/Object."<init>":()V
         4: return

  public java.lang.Object foo();
    flags: ACC_PUBLIC
    Code:
      stack=1, locals=1, args_size=1
         0: ldc #17 // MethodHandle invokevirtual java/lang/String.toUpperCase:()Ljava/lang/String;
         2: areturn
}