fieldDescriptor.hpp revision 3602:da91efe96a93 
1/*
2 * Copyright (c) 1997, 2012, 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_RUNTIME_FIELDDESCRIPTOR_HPP
26#define SHARE_VM_RUNTIME_FIELDDESCRIPTOR_HPP
27
28#include "oops/constantPool.hpp"
29#include "oops/symbol.hpp"
30#include "runtime/fieldType.hpp"
31#include "utilities/accessFlags.hpp"
32#include "utilities/constantTag.hpp"
33
34// A fieldDescriptor describes the attributes of a single field (instance or class variable).
35// It needs the class constant pool to work (because it only holds indices into the pool
36// rather than the actual info).
37
38class fieldDescriptor VALUE_OBJ_CLASS_SPEC {
39 private:
40  AccessFlags         _access_flags;
41  int                 _index; // the field index
42  constantPoolHandle  _cp;
43
44  // update the access_flags for the field in the klass
45  void update_klass_field_access_flag() {
46    InstanceKlass* ik = InstanceKlass::cast(field_holder());
47    ik->field(index())->set_access_flags(_access_flags.as_short());
48  }
49
50  FieldInfo* field() const {
51    InstanceKlass* ik = InstanceKlass::cast(field_holder());
52    return ik->field(_index);
53  }
54
55 public:
56  Symbol* name() const {
57    return field()->name(_cp);
58  }
59  Symbol* signature() const {
60    return field()->signature(_cp);
61  }
62  Klass* field_holder() const        { return _cp->pool_holder(); }
63  ConstantPool* constants() const    { return _cp(); }
64  AccessFlags access_flags() const     { return _access_flags; }
65  oop loader() const;
66  // Offset (in words) of field from start of instanceOop / Klass*
67  int offset() const                   { return field()->offset(); }
68  Symbol* generic_signature() const;
69  int index() const                    { return _index; }
70  AnnotationArray* annotations() const;
71
72  // Initial field value
73  bool has_initial_value() const          { return field()->initval_index() != 0; }
74  int initial_value_index() const         { return field()->initval_index(); }
75  constantTag initial_value_tag() const;  // The tag will return true on one of is_int(), is_long(), is_single(), is_double()
76  jint        int_initial_value() const;
77  jlong       long_initial_value() const;
78  jfloat      float_initial_value() const;
79  jdouble     double_initial_value() const;
80  oop         string_initial_value(TRAPS) const;
81
82  // Field signature type
83  BasicType field_type() const            { return FieldType::basic_type(signature()); }
84
85  // Access flags
86  bool is_public() const                  { return access_flags().is_public(); }
87  bool is_private() const                 { return access_flags().is_private(); }
88  bool is_protected() const               { return access_flags().is_protected(); }
89  bool is_package_private() const         { return !is_public() && !is_private() && !is_protected(); }
90
91  bool is_static() const                  { return access_flags().is_static(); }
92  bool is_final() const                   { return access_flags().is_final(); }
93  bool is_volatile() const                { return access_flags().is_volatile(); }
94  bool is_transient() const               { return access_flags().is_transient(); }
95
96  bool is_synthetic() const               { return access_flags().is_synthetic(); }
97
98  bool is_field_access_watched() const    { return access_flags().is_field_access_watched(); }
99  bool is_field_modification_watched() const
100                                          { return access_flags().is_field_modification_watched(); }
101  bool has_generic_signature() const      { return access_flags().field_has_generic_signature(); }
102
103  void set_is_field_access_watched(const bool value) {
104    _access_flags.set_is_field_access_watched(value);
105    update_klass_field_access_flag();
106  }
107
108  void set_is_field_modification_watched(const bool value) {
109    _access_flags.set_is_field_modification_watched(value);
110    update_klass_field_access_flag();
111  }
112
113  // Initialization
114  void initialize(InstanceKlass* ik, int index);
115
116  // Print
117  void print() { print_on(tty); }
118  void print_on(outputStream* st) const         PRODUCT_RETURN;
119  void print_on_for(outputStream* st, oop obj)  PRODUCT_RETURN;
120};
121
122#endif // SHARE_VM_RUNTIME_FIELDDESCRIPTOR_HPP
123