/*

 * Copyright 2003-2006 Sun Microsystems, Inc.  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

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,

 * CA 95054 USA or visit www.sun.com if you need additional information or

 * have any questions.

 *

 */

class DictionaryEntry;

//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

// The data structure for the system dictionary (and the shared system

// dictionary).

class Dictionary : public TwoOopHashtable {

  friend class VMStructs;

private:

  // current iteration index.

  static int                    _current_class_index;

  // pointer to the current hash table entry.

  static DictionaryEntry*       _current_class_entry;

  DictionaryEntry* get_entry(int index, unsigned int hash,

                             symbolHandle name, Handle loader);

  DictionaryEntry* bucket(int i) {

    return (DictionaryEntry*)Hashtable::bucket(i);

  }

  // The following method is not MT-safe and must be done under lock.

  DictionaryEntry** bucket_addr(int i) {

    return (DictionaryEntry**)Hashtable::bucket_addr(i);

  }

  void add_entry(int index, DictionaryEntry* new_entry) {

    Hashtable::add_entry(index, (HashtableEntry*)new_entry);

  }

public:

  Dictionary(int table_size);

  Dictionary(int table_size, HashtableBucket* t, int number_of_entries);

  DictionaryEntry* new_entry(unsigned int hash, klassOop klass, oop loader);

  DictionaryEntry* new_entry();

  void free_entry(DictionaryEntry* entry);

  void add_klass(symbolHandle class_name, Handle class_loader,KlassHandle obj);

  klassOop find_class(int index, unsigned int hash,

                      symbolHandle name, Handle loader);

  klassOop find_shared_class(int index, unsigned int hash, symbolHandle name);

  // Compiler support

  klassOop try_get_next_class();

  // GC support

  void oops_do(OopClosure* f);

  void always_strong_classes_do(OopClosure* blk);

  void classes_do(void f(klassOop));

  void classes_do(void f(klassOop, TRAPS), TRAPS);

  void classes_do(void f(klassOop, oop));

  void classes_do(void f(klassOop, oop, TRAPS), TRAPS);

  void methods_do(void f(methodOop));

  // Classes loaded by the bootstrap loader are always strongly reachable.

  // If we're not doing class unloading, all classes are strongly reachable.

  static bool is_strongly_reachable(oop class_loader, oop klass) {

    assert (klass != NULL, "should have non-null klass");

    return (class_loader == NULL || !ClassUnloading);

  }

  // Unload (that is, break root links to) all unmarked classes and

  // loaders.  Returns "true" iff something was unloaded.

  bool do_unloading(BoolObjectClosure* is_alive);

  // Protection domains

  klassOop find(int index, unsigned int hash, symbolHandle name,

                Handle loader, Handle protection_domain, TRAPS);

  bool is_valid_protection_domain(int index, unsigned int hash,

                                  symbolHandle name, Handle class_loader,

                                  Handle protection_domain);

  void add_protection_domain(int index, unsigned int hash,

                             instanceKlassHandle klass, Handle loader,

                             Handle protection_domain, TRAPS);

  // Sharing support

  void dump(SerializeOopClosure* soc);

  void restore(SerializeOopClosure* soc);

  void reorder_dictionary();

#ifndef PRODUCT

  void print();

#endif

  void verify();

};

// The following classes can be in dictionary.cpp, but we need these

// to be in header file so that SA's vmStructs can access.

class ProtectionDomainEntry :public CHeapObj {

  friend class VMStructs;

 public:

  ProtectionDomainEntry* _next;

  oop                    _protection_domain;

  ProtectionDomainEntry(oop protection_domain, ProtectionDomainEntry* next) {

    _protection_domain = protection_domain;

    _next              = next;

  }

  ProtectionDomainEntry* next() { return _next; }

  oop protection_domain() { return _protection_domain; }

};

// An entry in the system dictionary, this describes a class as

// { klassOop, loader, protection_domain }.

class DictionaryEntry : public HashtableEntry {

  friend class VMStructs;

 private:

  // Contains the set of approved protection domains that can access

  // this system dictionary entry.

  ProtectionDomainEntry* _pd_set;

  oop                    _loader;

 public:

  // Tells whether a protection is in the approved set.

  bool contains_protection_domain(oop protection_domain) const;

  // Adds a protection domain to the approved set.

  void add_protection_domain(oop protection_domain);

  klassOop klass() const { return (klassOop)literal(); }

  klassOop* klass_addr() { return (klassOop*)literal_addr(); }

  DictionaryEntry* next() const {

    return (DictionaryEntry*)HashtableEntry::next();

  }

  DictionaryEntry** next_addr() {

    return (DictionaryEntry**)HashtableEntry::next_addr();

  }

  oop loader() const { return _loader; }

  void set_loader(oop loader) { _loader = loader; }

  oop* loader_addr() { return &_loader; }

  ProtectionDomainEntry* pd_set() const { return _pd_set; }

  void set_pd_set(ProtectionDomainEntry* pd_set) { _pd_set = pd_set; }

  bool has_protection_domain() { return _pd_set != NULL; }

  // Tells whether the initiating class' protection can access the this _klass

  bool is_valid_protection_domain(Handle protection_domain) {

    if (!ProtectionDomainVerification) return true;

    if (!SystemDictionary::has_checkPackageAccess()) return true;

    return protection_domain() == NULL

         ? true

         : contains_protection_domain(protection_domain());

  }

  void protection_domain_set_oops_do(OopClosure* f) {

    for (ProtectionDomainEntry* current = _pd_set;

                                current != NULL;

                                current = current->_next) {

      f->do_oop(&(current->_protection_domain));

    }

  }

  void verify_protection_domain_set() {

    for (ProtectionDomainEntry* current = _pd_set;

                                current != NULL;

                                current = current->_next) {

      current->_protection_domain->verify();

    }

  }

  bool equals(symbolOop class_name, oop class_loader) const {

    klassOop klass = (klassOop)literal();

    return (instanceKlass::cast(klass)->name() == class_name &&

            _loader == class_loader);

  }

  void print() {

    int count = 0;

    for (ProtectionDomainEntry* current = _pd_set;

                                current != NULL;

                                current = current->_next) {

      count++;

    }

    tty->print_cr("pd set = #%d", count);

  }

};