[crac] RFR: Assume module jars persistent

[Dan Heidinga]

On Tue, 29 Nov 2022 18:06:30 GMT, Anton Kozlov <akozlov at openjdk.org> wrote:

> Jar files opened by URLClassLoaders are assumed persistent. We need to handle module Jars the same way to prevent CheckpointException as reported by [1] 
> 
> [1] https://mail.openjdk.org/pipermail/crac-dev/2022-November/000380.html

src/java.base/share/classes/jdk/internal/module/ModuleReferences.java line 247:

> 245:             this.jf = newJarFile(path);
> 246:             this.uri = uri;
> 247:             this.resource = new JDKResource() {

Would it be cleaner to implement this JDKResource subclass as a named class in `JarFileCRaCSupport` and wrap this logic so we have something like:

this.resource = JarFileCRaCSupport.wrapAndRegisterJarFile(this.jf);


It centralizes more of the Jar file support in one place....

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PR: https://git.openjdk.org/crac/pull/35