fieldDescriptor.hpp revision 2062:3582bf76420e 
1/*
2 * Copyright (c) 1997, 2010, 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
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23 */
24
25#ifndef SHARE_VM_RUNTIME_FIELDDESCRIPTOR_HPP
26#define SHARE_VM_RUNTIME_FIELDDESCRIPTOR_HPP
27
28#include "oops/constantPoolOop.hpp"
29#include "oops/klassOop.hpp"
30#include "oops/oop.inline.hpp"
31#include "oops/symbol.hpp"
32#include "runtime/fieldType.hpp"
33#include "utilities/accessFlags.hpp"
34#include "utilities/constantTag.hpp"
35
36// A fieldDescriptor describes the attributes of a single field (instance or class variable).
37// It needs the class constant pool to work (because it only holds indices into the pool
38// rather than the actual info).
39
40class fieldDescriptor VALUE_OBJ_CLASS_SPEC {
41 private:
42  AccessFlags         _access_flags;
43  int                 _name_index;
44  int                 _signature_index;
45  int                 _initial_value_index;
46  int                 _offset;
47  int                 _generic_signature_index;
48  int                 _index; // index into fields() array
49  constantPoolHandle  _cp;
50
51 public:
52  Symbol* name() const                 { return _cp->symbol_at(_name_index); }
53  Symbol* signature() const            { return _cp->symbol_at(_signature_index); }
54  klassOop field_holder() const        { return _cp->pool_holder(); }
55  constantPoolOop constants() const    { return _cp(); }
56  AccessFlags access_flags() const     { return _access_flags; }
57  oop loader() const;
58  // Offset (in words) of field from start of instanceOop / klassOop
59  int offset() const                   { return _offset; }
60  Symbol* generic_signature() const    { return (_generic_signature_index > 0 ? _cp->symbol_at(_generic_signature_index) : (Symbol*)NULL); }
61  int index() const                    { return _index; }
62  typeArrayOop annotations() const;
63
64  // Initial field value
65  bool has_initial_value() const          { return _initial_value_index != 0; }
66  constantTag initial_value_tag() const;  // The tag will return true on one of is_int(), is_long(), is_single(), is_double()
67  jint        int_initial_value() const;
68  jlong       long_initial_value() const;
69  jfloat      float_initial_value() const;
70  jdouble     double_initial_value() const;
71  oop         string_initial_value(TRAPS) const;
72
73  // Field signature type
74  BasicType field_type() const            { return FieldType::basic_type(signature()); }
75
76  // Access flags
77  bool is_public() const                  { return _access_flags.is_public(); }
78  bool is_private() const                 { return _access_flags.is_private(); }
79  bool is_protected() const               { return _access_flags.is_protected(); }
80  bool is_package_private() const         { return !is_public() && !is_private() && !is_protected(); }
81
82  bool is_static() const                  { return _access_flags.is_static(); }
83  bool is_final() const                   { return _access_flags.is_final(); }
84  bool is_volatile() const                { return _access_flags.is_volatile(); }
85  bool is_transient() const               { return _access_flags.is_transient(); }
86
87  bool is_synthetic() const               { return _access_flags.is_synthetic(); }
88
89  bool is_field_access_watched() const    { return _access_flags.is_field_access_watched(); }
90  bool is_field_modification_watched() const
91                                          { return _access_flags.is_field_modification_watched(); }
92  void set_is_field_access_watched(const bool value)
93                                          { _access_flags.set_is_field_access_watched(value); }
94  void set_is_field_modification_watched(const bool value)
95                                          { _access_flags.set_is_field_modification_watched(value); }
96
97  // Initialization
98  void initialize(klassOop k, int index);
99
100  // Print
101  void print_on(outputStream* st) const         PRODUCT_RETURN;
102  void print_on_for(outputStream* st, oop obj)  PRODUCT_RETURN;
103};
104
105#endif // SHARE_VM_RUNTIME_FIELDDESCRIPTOR_HPP
106