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
  17 #define _Jv_FIELD_UNRESOLVED_FLAG       0x8000
  18 #define _Jv_FIELD_CONSTANT_VALUE        0x4000
  19
  20 struct _Jv_Field
  21 {
  22 #ifndef COMPACT_FIELDS
  23   struct _Jv_Utf8Const* name;
  24 #endif
  25
  26   /* The type of the field, if isResolved().
  27      If !isResolved():  The fields's signature as a (Utf8Const*). */
  28   jclass                type;
  29
  30   _Jv_ushort            flags;
  31
  32 #ifdef COMPACT_FIELDS
  33   jshort                nameIndex;  /* offset in class's name table */
  34 #else
  35   _Jv_ushort            bsize;  /* not really needed ... */
  36 #endif
  37
  38   union {
  39     jint                boffset;  /* offset in bytes for instance field */
  40     void*               addr;  /* address of static field */
  41   } u;
  42
  43 #ifdef __cplusplus
  44   jboolean isResolved ()
  45   { return ! (flags & _Jv_FIELD_UNRESOLVED_FLAG); }
  46
  47   public:
  48
  49   int getOffset () { return u.boffset; }
  50
  51   jobject getObjectField (jobject obj)
  52   { return *(jobject *)((char *)obj + getOffset ()); }
  53
  54   jfieldID getNextField () { return this + 1; }
  55
  56   jboolean isRef ()
  57     {
  58       if (!isResolved ())
  59         {
  60           char first = ((_Jv_Utf8Const*)type)->data[0];
  61           return first == '[' || first == 'L';
  62         }
  63       else
  64         {
  65           return ! type->isPrimitive ();
  66         }
  67     }
  68
  69   jclass getClass ()
  70   {
  71     // We can't use JvAssert here because it is not in a public
  72     // header.
  73     // JvAssert (isResolved ());
  74     return type;
  75   }
  76
  77   // FIXME - may need to mask off internal flags.
  78   int getModifiers() { return flags; }
  79
  80 #ifdef COMPACT_FIELDS
  81   _Jv_Utf8Const * getNameUtf8Const (jclass cls)
  82   { return clas->fieldNames + nameIndex; }
  83 #else
  84   _Jv_Utf8Const * getNameUtf8Const (jclass) { return name; }
  85 #endif
  86 #endif
  87 };
  88
  89 #ifdef __cplusplus
  90
  91 inline jbyte
  92 _Jv_GetStaticByteField (jclass, _Jv_Field* field)
  93 {
  94   return * (jbyte *) field->u.addr;
  95 }
  96
  97 inline jshort
  98 _Jv_GetStaticShortField (jclass, _Jv_Field* field)
  99 {
 100   return * (jshort *) field->u.addr;
 101 }
 102
 103 inline jint
 104 _Jv_GetStaticIntField (jclass, _Jv_Field* field)
 105 {
 106   return * (jint *) field->u.addr;
 107 }
 108
 109 inline jlong
 110 _Jv_GetStaticLongField (jclass, _Jv_Field* field)
 111 {
 112   return * (jlong *) field->u.addr;
 113 }
 114
 115 inline jobject
 116 _Jv_GetObjectField (jobject obj, _Jv_Field* field)
 117 {
 118   return field->getObjectField (obj);
 119 }
 120
 121 inline jbyte
 122 _Jv_GetByteField (jobject obj, _Jv_Field* field)
 123 {
 124   return * (jbyte *) ((char*) obj + field->getOffset ());
 125 }
 126
 127 inline jshort
 128 _Jv_GetShortField (jobject obj, _Jv_Field* field)
 129 {
 130   return * (jshort *) ((char*) obj + field->getOffset ());
 131 }
 132 inline jint
 133 _Jv_GetIntField (jobject obj, _Jv_Field* field)
 134 {
 135   return * (jint *) ((char*) obj + field->getOffset ());
 136 }
 137 inline jlong
 138 _Jv_GetLongField (jobject obj, _Jv_Field* field)
 139 {
 140   return * (jlong *) ((char*) obj + field->getOffset ());
 141 }
 142
 143 extern inline jfieldID
 144 _Jv_FromReflectedField (java::lang::reflect::Field *field)
 145 {
 146   return (jfieldID) ((char *) field->declaringClass->fields + field->offset);
 147 }
 148
 149
 150 #ifdef __GCJ_CNI_H__
 151 extern inline jfieldID
 152 JvGetFirstInstanceField (jclass klass)
 153 {
 154   return &(klass->fields[klass->static_field_count]);
 155 }
 156
 157 extern inline jint
 158 JvNumInstanceFields (jclass klass)
 159 {
 160   return klass->field_count - klass->static_field_count;
 161 }
 162
 163 extern inline jfieldID
 164 JvGetFirstStaticField (jclass klass)
 165 {
 166   return &(klass->fields[0]);
 167 }
 168
 169 extern inline jint
 170 JvNumStaticFields (jclass klass)
 171 {
 172   return klass->static_field_count;
 173 }
 174
 175 extern inline jboolean
 176 JvFieldIsRef (jfieldID field)
 177 {
 178   // gnu.gcj.RawData.class is  _CL_Q33gnu3gcj7RawData
 179   extern java::lang::Class _CL_Q33gnu3gcj7RawData;
 180   return field->isRef () && field->type != &_CL_Q33gnu3gcj7RawData;
 181 }
 182
 183 extern inline jobject
 184 JvGetObjectField (jobject obj, _Jv_Field* field)
 185 {
 186   return _Jv_GetObjectField (obj, field);
 187 }
 188 #endif /* defined (__GCJ_CNI_H__) */
 189
 190 #endif /* __cplusplus */
 191
 192 #endif /* __GCJ_FIELD_H */