1 /*
   2  * Copyright (c) 1997, 2019, 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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  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 "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 
  40 class fieldDescriptor {
  41  private:
  42   AccessFlags         _access_flags;
  43   int                 _index; // the field index
  44   constantPoolHandle  _cp;
  45 
  46   // update the access_flags for the field in the klass
  47   inline void update_klass_field_access_flag();
  48 
  49   inline FieldInfo* field() const;
  50 
  51  public:
  52   fieldDescriptor() {
  53     DEBUG_ONLY(_index = badInt);
  54   }
  55   fieldDescriptor(InstanceKlass* ik, int index) {
  56     DEBUG_ONLY(_index = badInt);
  57     reinitialize(ik, index);
  58   }
  59   inline Symbol* name() const;
  60   inline Symbol* signature() const;
  61   inline InstanceKlass* field_holder() const;
  62   inline ConstantPool* constants() const;
  63 
  64   AccessFlags access_flags()      const    { return _access_flags; }
  65   oop loader()                    const;
  66   // Offset (in words) of field from start of instanceOop / Klass*
  67   inline int offset()             const;
  68   Symbol* generic_signature()     const;
  69   int index()                     const    { return _index; }
  70   AnnotationArray* annotations()  const;
  71   AnnotationArray* type_annotations()  const;
  72 
  73   // Initial field value
  74   inline bool has_initial_value()        const;
  75   inline int initial_value_index()       const;
  76   constantTag initial_value_tag() const;  // The tag will return true on one of is_int(), is_long(), is_single(), is_double()
  77   jint int_initial_value()        const;
  78   jlong long_initial_value()      const;
  79   jfloat float_initial_value()    const;
  80   jdouble double_initial_value()  const;
  81   oop string_initial_value(TRAPS) const;
  82 
  83   // Field signature type
  84   inline BasicType field_type() const;
  85 
  86   // Access flags
  87   bool is_public()                const    { return access_flags().is_public(); }
  88   bool is_private()               const    { return access_flags().is_private(); }
  89   bool is_protected()             const    { return access_flags().is_protected(); }
  90   bool is_package_private()       const    { return !is_public() && !is_private() && !is_protected(); }
  91 
  92   bool is_static()                const    { return access_flags().is_static(); }
  93   bool is_final()                 const    { return access_flags().is_final(); }
  94   bool is_stable()                const    { return access_flags().is_stable(); }
  95   bool is_volatile()              const    { return access_flags().is_volatile(); }
  96   bool is_transient()             const    { return access_flags().is_transient(); }
  97   inline bool is_flattened()      const;
  98   inline bool is_flattenable()    const;
  99 
 100   bool is_synthetic()             const    { return access_flags().is_synthetic(); }
 101 
 102   bool is_field_access_watched()  const    { return access_flags().is_field_access_watched(); }
 103   bool is_field_modification_watched() const
 104                                            { return access_flags().is_field_modification_watched(); }
 105   bool has_initialized_final_update() const { return access_flags().has_field_initialized_final_update(); }
 106   bool has_generic_signature()    const    { return access_flags().field_has_generic_signature(); }
 107 
 108   inline void set_is_field_access_watched(const bool value);
 109   inline void set_is_field_modification_watched(const bool value);
 110   inline void set_has_initialized_final_update(const bool value);
 111 
 112   // Initialization
 113   void reinitialize(InstanceKlass* ik, int index);
 114 
 115   // Print
 116   void print() const;
 117   void print_on(outputStream* st) const         PRODUCT_RETURN;
 118   void print_on_for(outputStream* st, oop obj)  PRODUCT_RETURN;
 119   void verify() const                           PRODUCT_RETURN;
 120 };
 121 
 122 #endif // SHARE_RUNTIME_FIELDDESCRIPTOR_HPP