1 /*
  2  * Copyright (c) 1997, 2021, 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.
 22  *
 23  */
 24 
 25 #ifndef SHARE_RUNTIME_FIELDDESCRIPTOR_HPP
 26 #define SHARE_RUNTIME_FIELDDESCRIPTOR_HPP
 27 
 28 #include "oops/constantPool.hpp"
 29 #include "oops/fieldInfo.hpp"
 30 #include "oops/instanceKlass.hpp"
 31 #include "oops/symbol.hpp"
 32 #include "utilities/accessFlags.hpp"
 33 #include "utilities/constantTag.hpp"
 34 
 35 // A fieldDescriptor describes the attributes of a single field (instance or class variable).
 36 // It needs the class constant pool to work (because it only holds indices into the pool
 37 // rather than the actual info).
 38 
 39 class fieldDescriptor {
 40  private:
 41   AccessFlags         _access_flags;
 42   int                 _index; // the field index
 43   constantPoolHandle  _cp;
 44 
 45   // update the access_flags for the field in the klass
 46   inline void update_klass_field_access_flag();
 47 
 48   inline FieldInfo* field() const;
 49 
 50  public:
 51   fieldDescriptor() {
 52     DEBUG_ONLY(_index = badInt);
 53   }
 54   fieldDescriptor(InstanceKlass* ik, int index) {
 55     DEBUG_ONLY(_index = badInt);
 56     reinitialize(ik, index);
 57   }
 58   inline Symbol* name() const;
 59   inline Symbol* signature() const;
 60   inline InstanceKlass* field_holder() const;
 61   inline ConstantPool* constants() const;
 62 
 63   AccessFlags access_flags()      const    { return _access_flags; }
 64   oop loader()                    const;
 65   // Offset (in words) of field from start of instanceOop / Klass*
 66   inline int offset()             const;
 67   Symbol* generic_signature()     const;
 68   int index()                     const    { return _index; }
 69   AnnotationArray* annotations()  const;
 70   AnnotationArray* type_annotations()  const;
 71 
 72   // Initial field value
 73   inline bool has_initial_value()        const;
 74   inline int initial_value_index()       const;
 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   inline BasicType field_type() const;
 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_stable()                const    { return access_flags().is_stable(); }
 94   bool is_volatile()              const    { return access_flags().is_volatile(); }
 95   bool is_transient()             const    { return access_flags().is_transient(); }
 96   inline bool is_inlined() const;
 97   inline bool is_inline_type()    const;
 98 
 99   bool is_synthetic()             const    { return access_flags().is_synthetic(); }
100 
101   bool is_field_access_watched()  const    { return access_flags().is_field_access_watched(); }
102   bool is_field_modification_watched() const
103                                            { return access_flags().is_field_modification_watched(); }
104   bool has_initialized_final_update() const { return access_flags().has_field_initialized_final_update(); }
105   bool has_generic_signature()    const    { return access_flags().field_has_generic_signature(); }
106 
107   bool is_trusted_final()         const;
108 
109   inline void set_is_field_access_watched(const bool value);
110   inline void set_is_field_modification_watched(const bool value);
111   inline void set_has_initialized_final_update(const bool value);
112 
113   // Initialization
114   void reinitialize(InstanceKlass* ik, int index);
115 
116   // Print
117   void print() const;
118   void print_on(outputStream* st) const;
119   void print_on_for(outputStream* st, oop obj);
120   void verify() const                           PRODUCT_RETURN;
121 };
122 
123 #endif // SHARE_RUNTIME_FIELDDESCRIPTOR_HPP