libjava/gcj/field.h

   1 // field.h - Header file for fieldID instances.  -*- c++ -*-
   2
   3 /* Copyright (C) 1998, 1999, 2000  Free Software Foundation
   4
   5    This file is part of libgcj.
   6
   7 This software is copyrighted work licensed under the terms of the
   8 Libgcj License.  Please consult the file "LIBGCJ_LICENSE" for
   9 details.  */
  10
  11 #ifndef __GCJ_FIELD_H__
  12 #define __GCJ_FIELD_H__
  13
  14 #include <java/lang/Class.h>
  15 #include <java/lang/reflect/Field.h>
  16 #include <java/lang/reflect/Modifier.h>
  17 #include <gnu/gcj/RawData.h>
  18
  19 #define _Jv_FIELD_UNRESOLVED_FLAG       0x8000
  20 #define _Jv_FIELD_CONSTANT_VALUE        0x4000
  21
  22 struct _Jv_Field
  23 {
  24 #ifndef COMPACT_FIELDS
  25   struct _Jv_Utf8Const* name;
  26 #endif
  27
  28   /* The type of the field, if isResolved().
  29      If !isResolved():  The fields's signature as a (Utf8Const*). */
  30   jclass                type;
  31
  32   _Jv_ushort            flags;
  33
  34 #ifdef COMPACT_FIELDS
  35   jshort                nameIndex;  /* offset in class's name table */
  36 #else
  37   _Jv_ushort            bsize;  /* not really needed ... */
  38 #endif
  39
  40   union {
  41     jint                boffset;  /* offset in bytes for instance field */
  42     void*               addr;  /* address of static field */
  43   } u;
  44
  45 #ifdef __cplusplus
  46   jboolean isResolved ()
  47   { return ! (flags & _Jv_FIELD_UNRESOLVED_FLAG); }
  48
  49   public:
  50
  51   int getOffset () { return u.boffset; }
  52
  53   jobject getObjectField (jobject obj)
  54   { return *(jobject *)((char *)obj + getOffset ()); }
  55
  56   jfieldID getNextField () { return this + 1; }
  57
  58   jboolean isRef ()
  59     {
  60       if (!isResolved ())
  61         {
  62           char first = ((_Jv_Utf8Const*)type)->data[0];
  63           return first == '[' || first == 'L';
  64         }
  65       else
  66         {
  67           return ! type->isPrimitive ();
  68         }
  69     }
  70
  71   jclass getClass ()
  72   {
  73     // We can't use JvAssert here because it is not in a public
  74     // header.
  75     // JvAssert (isResolved ());
  76     return type;
  77   }
  78
  79   // Need to mask off all unknown/internal flags before returning.
  80   int getModifiers()
  81   {
  82     return flags & java::lang::reflect::Modifier::ALL_FLAGS;
  83   }
  84
  85 #ifdef COMPACT_FIELDS
  86   _Jv_Utf8Const * getNameUtf8Const (jclass cls)
  87   { return clas->fieldNames + nameIndex; }
  88 #else
  89   _Jv_Utf8Const * getNameUtf8Const (jclass) { return name; }
  90 #endif
  91 #endif
  92 };
  93
  94 #ifdef __cplusplus
  95
  96 inline jbyte
  97 _Jv_GetStaticByteField (jclass, _Jv_Field* field)
  98 {
  99   return * (jbyte *) field->u.addr;
 100 }
 101
 102 inline jshort
 103 _Jv_GetStaticShortField (jclass, _Jv_Field* field)
 104 {
 105   return * (jshort *) field->u.addr;
 106 }
 107
 108 inline jint
 109 _Jv_GetStaticIntField (jclass, _Jv_Field* field)
 110 {
 111   return * (jint *) field->u.addr;
 112 }
 113
 114 inline jlong
 115 _Jv_GetStaticLongField (jclass, _Jv_Field* field)
 116 {
 117   return * (jlong *) field->u.addr;
 118 }
 119
 120 inline jobject
 121 _Jv_GetObjectField (jobject obj, _Jv_Field* field)
 122 {
 123   return field->getObjectField (obj);
 124 }
 125
 126 inline jbyte
 127 _Jv_GetByteField (jobject obj, _Jv_Field* field)
 128 {
 129   return * (jbyte *) ((char*) obj + field->getOffset ());
 130 }
 131
 132 inline jshort
 133 _Jv_GetShortField (jobject obj, _Jv_Field* field)
 134 {
 135   return * (jshort *) ((char*) obj + field->getOffset ());
 136 }
 137 inline jint
 138 _Jv_GetIntField (jobject obj, _Jv_Field* field)
 139 {
 140   return * (jint *) ((char*) obj + field->getOffset ());
 141 }
 142 inline jlong
 143 _Jv_GetLongField (jobject obj, _Jv_Field* field)
 144 {
 145   return * (jlong *) ((char*) obj + field->getOffset ());
 146 }
 147
 148 extern inline jfieldID
 149 _Jv_FromReflectedField (java::lang::reflect::Field *field)
 150 {
 151   return (jfieldID) ((char *) field->declaringClass->fields + field->offset);
 152 }
 153
 154
 155 #ifdef __GCJ_CNI_H__
 156 extern inline jfieldID
 157 JvGetFirstInstanceField (jclass klass)
 158 {
 159   return &(klass->fields[klass->static_field_count]);
 160 }
 161
 162 extern inline jint
 163 JvNumInstanceFields (jclass klass)
 164 {
 165   return klass->field_count - klass->static_field_count;
 166 }
 167
 168 extern inline jfieldID
 169 JvGetFirstStaticField (jclass klass)
 170 {
 171   return &(klass->fields[0]);
 172 }
 173
 174 extern inline jint
 175 JvNumStaticFields (jclass klass)
 176 {
 177   return klass->static_field_count;
 178 }
 179
 180 extern inline jboolean
 181 JvFieldIsRef (jfieldID field)
 182 {
 183   return field->isRef () && field->type != &gnu::gcj::RawData::class$;
 184 }
 185
 186 extern inline jobject
 187 JvGetObjectField (jobject obj, _Jv_Field* field)
 188 {
 189   return _Jv_GetObjectField (obj, field);
 190 }
 191 #endif /* defined (__GCJ_CNI_H__) */
 192
 193 #endif /* __cplusplus */
 194
 195 #endif /* __GCJ_FIELD_H */