8292068: Convert ModuleEntryTable into ResourceHashtable

Reviewed-by: iklam, lfoltan

Author: coleenp

src/hotspot/share/classfile/classLoaderData.cpp

@@ -400,13 +400,7 @@ void ClassLoaderData::modules_do(void f(ModuleEntry*)) {
     f(_unnamed_module);
   }
   if (_modules != NULL) {
-    for (int i = 0; i < _modules->table_size(); i++) {
-      for (ModuleEntry* entry = _modules->bucket(i);
-           entry != NULL;
-           entry = entry->next()) {
-        f(entry);
-      }
-    }
+    _modules->modules_do(f);
   }
 }
 
@@ -592,7 +586,7 @@ ModuleEntryTable* ClassLoaderData::modules() {
     MutexLocker m1(Module_lock);
     // Check if _modules got allocated while we were waiting for this lock.
     if ((modules = _modules) == NULL) {
-      modules = new ModuleEntryTable(ModuleEntryTable::_moduletable_entry_size);
+      modules = new ModuleEntryTable();
 
       {
         MutexLocker m1(metaspace_lock(), Mutex::_no_safepoint_check_flag);
@@ -715,7 +709,7 @@ ClassLoaderData::~ClassLoaderData() {
   }
 
   if (_unnamed_module != NULL) {
-    _unnamed_module->delete_unnamed_module();
+    delete _unnamed_module;
     _unnamed_module = NULL;
   }
 
@@ -1040,6 +1034,10 @@ void ClassLoaderData::verify() {
     k->verify();
     assert(k != k->next_link(), "no loops!");
   }
+
+  if (_modules != NULL) {
+    _modules->verify();
+  }
 }
 
 bool ClassLoaderData::contains_klass(Klass* klass) {

src/hotspot/share/classfile/classLoaderExt.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2015, 2021, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2015, 2022, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -81,17 +81,22 @@ void ClassLoaderExt::setup_app_search_path(JavaThread* current) {
 
 void ClassLoaderExt::process_module_table(JavaThread* current, ModuleEntryTable* met) {
   ResourceMark rm(current);
-  for (int i = 0; i < met->table_size(); i++) {
-    for (ModuleEntry* m = met->bucket(i); m != NULL;) {
+  class Process : public ModuleClosure {
+    JavaThread* _current;
+   public:
+    Process(JavaThread* current) : _current(current) {}
+    void do_module(ModuleEntry* m) {
       char* path = m->location()->as_C_string();
       if (strncmp(path, "file:", 5) == 0) {
         path = ClassLoader::skip_uri_protocol(path);
-        ClassLoader::setup_module_search_path(current, path);
+        ClassLoader::setup_module_search_path(_current, path);
       }
-      m = m->next();
     }
-  }
+  };
+  Process process(current);
+  met->modules_do(&process);
 }
+
 void ClassLoaderExt::setup_module_paths(JavaThread* current) {
   Arguments::assert_is_dumping_archive();
   _app_module_paths_start_index = ClassLoader::num_boot_classpath_entries() +