RFR: 8371418: Methods in AdapterHandlerLibrary use HashtableBase iterate method incorrectly

[Vladimir Kozlov]

On Fri, 7 Nov 2025 14:38:48 GMT, Ashutosh Mehra <asmehra at openjdk.org> wrote:

> The closure passed to `HashTable::iterate` in `AdapterHandlerLibrary::contains` and `AdapterHandlerLibrary::print_handler_on` is returning incorrect value. If the search is successful, it should return false to terminate the iteration, but it is returning true. This patch fixes the return value of these closures.
> In addition, I noticed `CompactHashTable::iterate` goes through all entries unconditionally, which is not optimal for cases where we may want to terminate the iteration when some condition is met. This is the case in `AdapterHandlerLibrary::contains` and `AdapterHandlerLibrary::print_handler_on` when it iterates over `_aot_adapter_handler_table`. This patch updates `CompactHashTable::iterate` to be the same as `HashTAble::iterate` by using return value of the closure to determine if the iteration should continue or abort. It also adds `CompactHashTable::iterate_all` to iterate all the values unconditionally and the users of `CompactHashTable::iterate` are updated to use `CompactHashTable::iterate_all`.

src/hotspot/share/classfile/compactHashtable.hpp line 309:

> 307: 
> 308:   template<typename Function>
> 309:   inline void iterate(Function& function) const { // lambda enabled API

Add comment explaining when it is exiting, when iteration is interrupted to show difference from `iterate_all()`

src/hotspot/share/runtime/sharedRuntime.cpp line 3415:

> 3413: #endif // INCLUDE_CDS
> 3414:   if (!found) {
> 3415:     auto findblob_runtime_table = [&] (AdapterFingerPrint* key, AdapterHandlerEntry* handler) {

Why do you need to pass `AdapterFingerPrint* key` argument which is not used here?

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PR Review Comment: https://git.openjdk.org/jdk/pull/28197#discussion_r2504305349
PR Review Comment: https://git.openjdk.org/jdk/pull/28197#discussion_r2504312085