RFR: 8352435: Refactor CDS test library for execution and module packaging

[Ioi Lam]

In CDS/AOT testing, we have a lot of code that deal with compiling/packaging modules, as well as running various child processes for the training/assembly/production phases.

Currently, these operations are done in many low-level steps, so it's difficult to understand and maintain:

https://github.com/openjdk/jdk/blob/fcc2a24291d499f7149debad1250903ddc369d91/test/hotspot/jtreg/runtime/cds/appcds/jigsaw/modulepath/ExportModule.java

This PR adds a few new classes to simplify the test cases:

Example: build two modular JAR files into `modulePath`


CDSModulePackager modulePackager = new CDSModulePackager(SRC);
modulePath = modulePackager.getOutputDir().toString();

modulePackager.createModularJar("com.foos");
modulePackager.createModularJar("com.needsfoosaddexport",
                                "--add-exports",
                                "com.foos/com.foos.internal=com.needsfoosaddexport");


Example: use modules in training/assembly/production phases


SimpleCDSAppTester.of("moduleNeedsJdkAddExport")
   .classpath(dummyJar)
   .modulepath(modulePath)
   .addVmArgs("--add-modules", "com.needsjdkaddexport",
              "--add-exports", "java.base/jdk.internal.misc=com.needsjdkaddexport", "-Xlog:cds")
   .appCommandLine("-m", "com.needsjdkaddexport/com.needsjdkaddexport.Main")
   .setAssemblyChecker((OutputAnalyzer out) -> {
           out.shouldContain("Full module graph = enabled");
        })
    .setProductionChecker((OutputAnalyzer out) -> {
            out.shouldContain("use_full_module_graph = true; java.base");
        })
    .runStaticWorkflow()
    .runAOTWorkflow();

-------------

Commit messages:
 - added comments
 - Prototype: support --add-exports in CDS FMG

Changes: https://git.openjdk.org/jdk/pull/24122/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=24122&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8352435
  Stats: 1130 lines in 7 files changed: 734 ins; 342 del; 54 mod
  Patch: https://git.openjdk.org/jdk/pull/24122.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/24122/head:pull/24122

PR: https://git.openjdk.org/jdk/pull/24122