On Thu, 16 Feb 2023 19:35:54 GMT, David M. Lloyd <d...@openjdk.org> wrote:
>> The class generated for lambda proxies is now defined as a hidden class.
>> This means that the counter, which was used to ensure a unique class name
>> and avoid clashes, is now redundant. In addition to performing redundant
>> work, this also impacts build reproducibility for native image generators
>> which might already have a strategy to cope with hidden classes but cannot
>> cope with indeterminate definition order for lambda proxy classes.
>>
>> This solves JDK-8292914 by making lambda proxy names always be stable
>> without any configuration needed. This would also replace #10024.
>
> David M. Lloyd has updated the pull request incrementally with one additional
> commit since the last revision:
>
> Use a unique index for the dumped lambda class instead of a time stamp
src/java.base/share/classes/java/lang/invoke/InnerClassLambdaMetafactory.java
line 208:
> 206: name = name.replace('/', '_');
> 207: }
> 208: return name.replace('.', '/') + "$$Lambda$";
Using `String::concat` uses the same code path as indy‑based String
concatenation[^1].
Suggestion:
return name.replace('.', '/').concat("$$Lambda");
[^1]: The JDK uses `StringBuilder`‑based String concatenation:
https://github.com/openjdk/jdk/blob/a39cf2e3b242298fbf5fafdb8aa9b5d4562061ef/make/modules/java.base/Java.gmk#L28
src/java.base/share/classes/java/lang/invoke/ProxyClassesDumper.java line 103:
> 101: final int len = className.length();
> 102: // add some padding to `len` for the index
> 103: StringBuilder sb = new StringBuilder(len + 5);
Suggestion:
StringBuilder sb = new StringBuilder(len + 6);
src/java.base/share/classes/java/lang/invoke/ProxyClassesDumper.java line 124:
> 122: }
> 123: }
> 124: sb.append(counter.incrementAndGet());
Suggestion:
sb.append('$').append(counter.incrementAndGet());
-------------
PR: https://git.openjdk.org/jdk/pull/12579
