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     char*               addr;  /* address of static field */
  43
  44     jobject* object_addr;  /* address of static object field... etc */
  45     jbyte* byte_addr;
  46     jshort* short_addr;
  47     jchar* char_addr;
  48     jint* int_addr;
  49     jlong* long_addr;
  50     jfloat* float_addr;
  51     jdouble* double_addr;
  52   } u;
  53
  54 #ifdef __cplusplus
  55   jboolean isResolved ()
  56   { return ! (flags & _Jv_FIELD_UNRESOLVED_FLAG); }
  57
  58   public:
  59
  60   int getOffset () { return u.boffset; }
  61
  62   jobject getObjectField (jobject obj)
  63   { return *(jobject *)((char *)obj + getOffset ()); }
  64
  65   jfieldID getNextField () { return this + 1; }
  66
  67   jboolean isRef ()
  68     {
  69       if (!isResolved ())
  70         {
  71           char first = ((_Jv_Utf8Const*)type)->first();
  72           return first == '[' || first == 'L';
  73         }
  74       else
  75         {
  76           return ! type->isPrimitive ();
  77         }
  78     }
  79
  80   jclass getClass ()
  81   {
  82     // We can't use JvAssert here because it is not in a public
  83     // header.
  84     // JvAssert (isResolved ());
  85     return type;
  86   }
  87
  88   // Need to mask off all unknown/internal flags before returning.
  89   int getModifiers()
  90   {
  91     return flags & java::lang::reflect::Modifier::ALL_FLAGS;
  92   }
  93
  94 #ifdef COMPACT_FIELDS
  95   _Jv_Utf8Const * getNameUtf8Const (jclass cls)
  96   { return clas->fieldNames + nameIndex; }
  97 #else
  98   _Jv_Utf8Const * getNameUtf8Const (jclass) { return name; }
  99 #endif
 100 #endif
 101 };
 102
 103 #ifdef __cplusplus
 104
 105 inline jbyte
 106 _Jv_GetStaticByteField (jclass, _Jv_Field* field)
 107 {
 108   return * (jbyte *) field->u.addr;
 109 }
 110
 111 inline jshort
 112 _Jv_GetStaticShortField (jclass, _Jv_Field* field)
 113 {
 114   return * (jshort *) field->u.addr;
 115 }
 116
 117 inline jint
 118 _Jv_GetStaticIntField (jclass, _Jv_Field* field)
 119 {
 120   return * (jint *) field->u.addr;
 121 }
 122
 123 inline jlong
 124 _Jv_GetStaticLongField (jclass, _Jv_Field* field)
 125 {
 126   return * (jlong *) field->u.addr;
 127 }
 128
 129 inline jobject
 130 _Jv_GetObjectField (jobject obj, _Jv_Field* field)
 131 {
 132   return field->getObjectField (obj);
 133 }
 134
 135 inline jbyte
 136 _Jv_GetByteField (jobject obj, _Jv_Field* field)
 137 {
 138   return * (jbyte *) ((char*) obj + field->getOffset ());
 139 }
 140
 141 inline jshort
 142 _Jv_GetShortField (jobject obj, _Jv_Field* field)
 143 {
 144   return * (jshort *) ((char*) obj + field->getOffset ());
 145 }
 146 inline jint
 147 _Jv_GetIntField (jobject obj, _Jv_Field* field)
 148 {
 149   return * (jint *) ((char*) obj + field->getOffset ());
 150 }
 151 inline jlong
 152 _Jv_GetLongField (jobject obj, _Jv_Field* field)
 153 {
 154   return * (jlong *) ((char*) obj + field->getOffset ());
 155 }
 156
 157 extern inline jfieldID
 158 _Jv_FromReflectedField (java::lang::reflect::Field *field)
 159 {
 160   return (jfieldID) ((char *) field->declaringClass->fields + field->offset);
 161 }
 162
 163
 164 #ifdef __GCJ_CNI_H__
 165 extern inline jfieldID
 166 JvGetFirstInstanceField (jclass klass)
 167 {
 168   return &(klass->fields[klass->static_field_count]);
 169 }
 170
 171 extern inline jint
 172 JvNumInstanceFields (jclass klass)
 173 {
 174   return klass->field_count - klass->static_field_count;
 175 }
 176
 177 extern inline jfieldID
 178 JvGetFirstStaticField (jclass klass)
 179 {
 180   return &(klass->fields[0]);
 181 }
 182
 183 extern inline jint
 184 JvNumStaticFields (jclass klass)
 185 {
 186   return klass->static_field_count;
 187 }
 188
 189 extern inline jboolean
 190 JvFieldIsRef (jfieldID field)
 191 {
 192   return field->isRef () && field->type != &gnu::gcj::RawData::class$;
 193 }
 194
 195 extern inline jobject
 196 JvGetObjectField (jobject obj, _Jv_Field* field)
 197 {
 198   return _Jv_GetObjectField (obj, field);
 199 }
 200 #endif /* defined (__GCJ_CNI_H__) */
 201
 202 #endif /* __cplusplus */
 203
 204 #endif /* __GCJ_FIELD_H */