RFR: 8374308: ImageBufferCache does not work as intended [v2]

[Alan Bateman]

On Mon, 5 Jan 2026 17:41:31 GMT, David Beaumont <duke at openjdk.org> wrote:

>> Remove ineffective/unused ImageBufferCache class, and simplify callers / remove dead code.
>> 
>> I removed the release methods in the internal classes, but the public ModuleReader API method is still there (the override can go away though since the default implementation also tests for non-null, so removing the override has no risk).
>> 
>> I suspect there are no implementations of ModuleReader that implement release semantics after this change, so perhaps we could relax the documentation around it? Thoughts welcome.
>
> David Beaumont has updated the pull request incrementally with one additional commit since the last revision:
> 
>   actually remove the class ...

src/java.base/share/classes/jdk/internal/jimage/BasicImageReader.java line 392:

> 390:     private static ByteBuffer allocateBuffer(long size) {
> 391:         if (size < 0 || Integer.MAX_VALUE < size) {
> 392:             throw new IndexOutOfBoundsException("size");

I don't think it can happen but I assume IAE would be more appropriate here as size is not an index.

src/java.base/share/classes/jdk/internal/jimage/BasicImageReader.java line 394:

> 392:             throw new IndexOutOfBoundsException("size");
> 393:         }
> 394:         ByteBuffer result = ByteBuffer.allocateDirect((int) ((size + 0xFFF) & ~0xFFF));

Can you remind me why it allocates multiples of 4k?

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PR Review Comment: https://git.openjdk.org/jdk/pull/29043#discussion_r2662336397
PR Review Comment: https://git.openjdk.org/jdk/pull/29043#discussion_r2662334175