1 /*
   2  * Copyright (c) 1997, 2013, 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_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 
  38 class 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 = field_holder();
  47     ik->field(index())->set_access_flags(_access_flags.as_short());
  48   }
  49 
  50   FieldInfo* field() const {
  51     InstanceKlass* ik = field_holder();
  52     return ik->field(_index);
  53   }
  54 
  55  public:
  56   fieldDescriptor() {
  57     DEBUG_ONLY(_index = badInt);
  58   }
  59   fieldDescriptor(InstanceKlass* ik, int index) {
  60     DEBUG_ONLY(_index = badInt);
  61     reinitialize(ik, index);
  62   }
  63   Symbol* name() const {
  64     return field()->name(_cp);
  65   }
  66   Symbol* signature() const {
  67     return field()->signature(_cp);
  68   }
  69   InstanceKlass* field_holder()   const    { return _cp->pool_holder(); }
  70   ConstantPool* constants()       const    { return _cp(); }
  71   AccessFlags access_flags()      const    { return _access_flags; }
  72   oop loader()                    const;
  73   // Offset (in words) of field from start of instanceOop / Klass*
  74   int offset()                    const    { return field()->offset(); }
  75   Symbol* generic_signature()     const;
  76   int index()                     const    { return _index; }
  77   AnnotationArray* annotations()  const;
  78   AnnotationArray* type_annotations()  const;
  79 
  80   // Initial field value
  81   bool has_initial_value()        const    { return field()->initval_index() != 0; }
  82   int initial_value_index()       const    { return field()->initval_index(); }
  83   constantTag initial_value_tag() const;  // The tag will return true on one of is_int(), is_long(), is_single(), is_double()
  84   jint int_initial_value()        const;
  85   jlong long_initial_value()      const;
  86   jfloat float_initial_value()    const;
  87   jdouble double_initial_value()  const;
  88   oop string_initial_value(TRAPS) const;
  89 
  90   // Field signature type
  91   BasicType field_type()          const    { return FieldType::basic_type(signature()); }
  92 
  93   // Access flags
  94   bool is_public()                const    { return access_flags().is_public(); }
  95   bool is_private()               const    { return access_flags().is_private(); }
  96   bool is_protected()             const    { return access_flags().is_protected(); }
  97   bool is_package_private()       const    { return !is_public() && !is_private() && !is_protected(); }
  98 
  99   bool is_static()                const    { return access_flags().is_static(); }
 100   bool is_final()                 const    { return access_flags().is_final(); }

 101   bool is_volatile()              const    { return access_flags().is_volatile(); }
 102   bool is_transient()             const    { return access_flags().is_transient(); }
 103 
 104   bool is_synthetic()             const    { return access_flags().is_synthetic(); }
 105 
 106   bool is_field_access_watched()  const    { return access_flags().is_field_access_watched(); }
 107   bool is_field_modification_watched() const
 108                                            { return access_flags().is_field_modification_watched(); }
 109   bool has_initialized_final_update() const { return access_flags().has_field_initialized_final_update(); }
 110   bool has_generic_signature()    const    { return access_flags().field_has_generic_signature(); }
 111 
 112   void set_is_field_access_watched(const bool value) {
 113     _access_flags.set_is_field_access_watched(value);
 114     update_klass_field_access_flag();
 115   }
 116 
 117   void set_is_field_modification_watched(const bool value) {
 118     _access_flags.set_is_field_modification_watched(value);
 119     update_klass_field_access_flag();
 120   }
 121 
 122   void set_has_initialized_final_update(const bool value) {
 123     _access_flags.set_has_field_initialized_final_update(value);
 124     update_klass_field_access_flag();
 125   }
 126 
 127   // Initialization
 128   void reinitialize(InstanceKlass* ik, int index);
 129 
 130   // Print
 131   void print() { print_on(tty); }
 132   void print_on(outputStream* st) const         PRODUCT_RETURN;
 133   void print_on_for(outputStream* st, oop obj)  PRODUCT_RETURN;
 134   void verify() const                           PRODUCT_RETURN;
 135 };
 136 
 137 #endif // SHARE_VM_RUNTIME_FIELDDESCRIPTOR_HPP
--- EOF ---