RFR (L) 8037210: Get rid of char-based descriptions 'J' of basic types

Christian Thalinger christian.thalinger at oracle.com
Wed Mar 19 01:18:06 UTC 2014

On Mar 18, 2014, at 2:35 PM, John Rose <john.r.rose at oracle.com> wrote:

> On Mar 18, 2014, at 1:36 PM, Christian Thalinger <christian.thalinger at oracle.com> wrote:
>> Why are we not using an Enum instead of an "untyped" byte?
> Byte is moderately typed, in the sense (which I rely on during development) that you can't assign an int or char to a byte w/o a cast.
> That's why it is not just a plain int.
> But those values (L_TYPE etc.) are used a lot as numbers, and specifically as low-level array indexes, and also comparisons (x < V_TYPE).
> To turn them into enums, we'd have to add lots of calls to '.ordinal()' to turn them right back to numbers.  That dilutes (completely IMO) the value they have as enums to raise the level of the code.

But without being strongly typed we get bugs like this one:
-    MethodHandle bindArgument(int pos, char basicType, Object value) {
+    MethodHandle bindArgument(int pos, byte basicType, Object value) {
         // If the member needs dispatching, do so.
         if (pos == 0 && basicType == 'L') {
I’m just saying that for the sake of maintainability and correctness an Enum would be better.

> — John
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