1/*
2 * Copyright (c) 2011, 2014, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
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23 */
24
25#ifndef SHARE_VM_OOPS_METADATA_HPP
26#define SHARE_VM_OOPS_METADATA_HPP
27
28#include "utilities/exceptions.hpp"
29#include "utilities/globalDefinitions.hpp"
30#include "utilities/ostream.hpp"
31
32// This is the base class for an internal Class related metadata
33class Metadata : public MetaspaceObj {
34  // Debugging hook to check that the metadata has not been deleted.
35  NOT_PRODUCT(int _valid;)
36 public:
37  NOT_PRODUCT(Metadata()     { _valid = 0; })
38  NOT_PRODUCT(bool is_valid() const volatile { return _valid == 0; })
39
40  int identity_hash()                { return (int)(uintptr_t)this; }
41
42  // Rehashing support for tables containing pointers to this
43  unsigned int new_hash(juint seed)   { ShouldNotReachHere();  return 0; }
44
45  virtual bool is_metadata()           const volatile { return true; }
46  virtual bool is_klass()              const volatile { return false; }
47  virtual bool is_method()             const volatile { return false; }
48  virtual bool is_methodData()         const volatile { return false; }
49  virtual bool is_constantPool()       const volatile { return false; }
50  virtual bool is_methodCounters()     const volatile { return false; }
51  virtual int  size()                  const = 0;
52  virtual MetaspaceObj::Type type()    const = 0;
53  virtual const char* internal_name()  const = 0;
54  virtual void metaspace_pointers_do(MetaspaceClosure* iter) {}
55
56  void print()       const { print_on(tty); }
57  void print_value() const { print_value_on(tty); }
58
59  void print_maybe_null() const { print_on_maybe_null(tty); }
60  void print_on_maybe_null(outputStream* st) const {
61    if (this == NULL)
62      st->print("NULL");
63    else
64      print_on(st);
65  }
66  void print_value_on_maybe_null(outputStream* st) const {
67    if (this == NULL)
68      st->print("NULL");
69    else
70      print_value_on(st);
71  }
72
73  virtual void print_on(outputStream* st) const;       // First level print
74  virtual void print_value_on(outputStream* st) const = 0; // Second level print
75
76  char* print_value_string() const;
77
78  // Used to keep metadata alive during class redefinition
79  // Can't assert because is called for delete functions (as an assert)
80  virtual bool on_stack() const { return false; }
81  virtual void set_on_stack(const bool value);
82
83  // Set on_stack bit, so that the metadata is not cleared
84  // during class redefinition.  This is a virtual call because only methods
85  // and constant pools need to be set, but someday instanceKlasses might also.
86  static void mark_on_stack(Metadata* m) { m->set_on_stack(true); }
87};
88
89#endif // SHARE_VM_OOPS_METADATA_HPP
90