libjava/java/lang/Class.h

   1 // Class.h - Header file for java.lang.Class.  -*- c++ -*-
   2
   3 /* Copyright (C) 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005  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 // Written primary using compiler source and Class.java as guides.
  12 #ifndef __JAVA_LANG_CLASS_H__
  13 #define __JAVA_LANG_CLASS_H__
  14
  15 #pragma interface
  16
  17 #include <stddef.h>
  18 #include <java/lang/Object.h>
  19 #include <java/lang/String.h>
  20 #include <java/net/URL.h>
  21 #include <java/lang/reflect/Modifier.h>
  22 #include <java/security/ProtectionDomain.h>
  23 #include <java/lang/Package.h>
  24 #include <gnu/gcj/runtime/StackTrace.h>
  25
  26 // We declare these here to avoid including gcj/cni.h.
  27 extern "C" void _Jv_InitClass (jclass klass);
  28 extern "C" void _Jv_RegisterClasses (const jclass *classes);
  29 extern "C" void _Jv_RegisterClasses_Counted (const jclass *classes,
  30                                              size_t count);
  31
  32 // This must be predefined with "C" linkage.
  33 extern "C" void *_Jv_LookupInterfaceMethodIdx (jclass klass, jclass iface,
  34                                                int meth_idx);
  35
  36 // These are the possible values for the `state' field of the class
  37 // structure.  Note that ordering is important here.  Whenever the
  38 // state changes, one should notify all waiters of this class.
  39 enum
  40 {
  41   JV_STATE_NOTHING = 0,         // Set by compiler.
  42
  43   JV_STATE_PRELOADING = 1,      // Can do _Jv_FindClass.
  44   JV_STATE_LOADING = 3,         // Has super installed.
  45   JV_STATE_READ = 4,            // Has been completely defined.
  46   JV_STATE_LOADED = 5,          // Has Miranda methods defined.
  47
  48   JV_STATE_COMPILED = 6,        // This was a compiled class.
  49
  50   JV_STATE_PREPARED = 7,        // Layout & static init done.
  51   JV_STATE_LINKED = 9,          // Strings interned.
  52
  53   JV_STATE_IN_PROGRESS = 10,    // <clinit> running.
  54
  55   JV_STATE_ERROR = 12,
  56
  57   JV_STATE_DONE = 14            // Must be last.
  58 };
  59
  60 struct _Jv_Field;
  61 struct _Jv_VTable;
  62 union _Jv_word;
  63 struct _Jv_ArrayVTable;
  64 class _Jv_Linker;
  65 class _Jv_ExecutionEngine;
  66 class _Jv_CompiledEngine;
  67 class _Jv_InterpreterEngine;
  68
  69 struct _Jv_Constants
  70 {
  71   jint size;
  72   jbyte *tags;
  73   _Jv_word *data;
  74 };
  75
  76 struct _Jv_Method
  77 {
  78   // Method name.
  79   _Jv_Utf8Const *name;
  80   // Method signature.
  81   _Jv_Utf8Const *signature;
  82   // Access flags.
  83   _Jv_ushort accflags;
  84   // Method's index in the vtable.
  85   _Jv_ushort index;
  86   // Pointer to underlying function.
  87   void *ncode;
  88   // NULL-terminated list of exception class names; can be NULL if
  89   // there are none such.
  90   _Jv_Utf8Const **throws;
  91
  92   _Jv_Method *getNextMethod ()
  93   { return this + 1; }
  94 };
  95
  96 // Interface Dispatch Tables
  97 union _Jv_IDispatchTable
  98 {
  99   struct
 100   {
 101     // Index into interface's ioffsets.
 102     jshort iindex;
 103     jshort itable_length;
 104     // Class Interface dispatch table.
 105     void **itable;
 106   } cls;
 107
 108   struct
 109   {
 110     // Offsets into implementation class itables.
 111     jshort *ioffsets;
 112   } iface;
 113 };
 114
 115 // Used by _Jv_Linker::get_interfaces ()
 116 struct _Jv_ifaces
 117 {
 118   jclass *list;
 119   jshort len;
 120   jshort count;
 121 };
 122
 123 struct _Jv_MethodSymbol
 124 {
 125   _Jv_Utf8Const *class_name;
 126   _Jv_Utf8Const *name;
 127   _Jv_Utf8Const *signature;
 128 };
 129
 130 struct _Jv_OffsetTable
 131 {
 132   jint state;
 133   jint offsets[];
 134 };
 135
 136 struct _Jv_AddressTable
 137 {
 138   jint state;
 139   void *addresses[];
 140 };
 141
 142 struct _Jv_CatchClass
 143 {
 144   java::lang::Class **address;
 145   _Jv_Utf8Const *classname;
 146 };
 147
 148 // Possible values for the assertion_code field in the type assertion table.
 149 enum
 150 {
 151   JV_ASSERT_END_OF_TABLE = 0,
 152   JV_ASSERT_TYPES_COMPATIBLE = 1,
 153   JV_ASSERT_IS_INSTANTIABLE = 2
 154 };
 155
 156 // Entry in the type assertion table, used to validate type constraints
 157 // for binary compatibility.
 158 struct _Jv_TypeAssertion
 159 {
 160   jint assertion_code;
 161   _Jv_Utf8Const *op1;
 162   _Jv_Utf8Const *op2;
 163 };
 164
 165 #define JV_PRIMITIVE_VTABLE ((_Jv_VTable *) -1)
 166
 167 #define JV_CLASS(Obj) ((jclass) (*(_Jv_VTable **) Obj)->clas)
 168
 169 // Forward declarations for friends of java::lang::Class
 170
 171 // Friend functions implemented in natClass.cc.
 172 _Jv_Method *_Jv_GetMethodLocal (jclass klass, _Jv_Utf8Const *name,
 173                                 _Jv_Utf8Const *signature);
 174 jboolean _Jv_IsAssignableFrom (jclass, jclass);
 175 jboolean _Jv_IsAssignableFromSlow (jclass, jclass);
 176 jboolean _Jv_InterfaceAssignableFrom (jclass, jclass);
 177
 178 _Jv_Method* _Jv_LookupDeclaredMethod (jclass, _Jv_Utf8Const *,
 179                                       _Jv_Utf8Const*, jclass * = NULL);
 180 jfieldID JvGetFirstInstanceField (jclass);
 181 jint JvNumInstanceFields (jclass);
 182 jfieldID JvGetFirstStaticField (jclass);
 183 jint JvNumStaticFields (jclass);
 184
 185 jobject _Jv_AllocObject (jclass);
 186 void *_Jv_AllocObj (jint, jclass);
 187 void *_Jv_AllocPtrFreeObj (jint, jclass);
 188 void *_Jv_AllocArray (jint, jclass);
 189
 190 bool _Jv_getInterfaceMethod(jclass, jclass&, int&,
 191                             const _Jv_Utf8Const*,
 192                             const _Jv_Utf8Const*);
 193
 194 jobject _Jv_JNI_ToReflectedField (_Jv_JNIEnv *, jclass, jfieldID,
 195                                   jboolean);
 196 jobject _Jv_JNI_ToReflectedMethod (_Jv_JNIEnv *, jclass, jmethodID,
 197                                    jboolean);
 198 jfieldID _Jv_FromReflectedField (java::lang::reflect::Field *);
 199
 200 jmethodID _Jv_FromReflectedMethod (java::lang::reflect::Method *);
 201 jmethodID _Jv_FromReflectedConstructor (java::lang::reflect::Constructor *);
 202 jint JvNumMethods (jclass);
 203 jmethodID JvGetFirstMethod (jclass);
 204
 205 // Friend classes and functions to implement the ClassLoader
 206 class java::lang::ClassLoader;
 207 class java::lang::VMClassLoader;
 208
 209 class java::io::ObjectOutputStream;
 210 class java::io::ObjectInputStream;
 211 class java::io::ObjectStreamClass;
 212
 213 void _Jv_RegisterClassHookDefault (jclass klass);
 214 void _Jv_RegisterInitiatingLoader (jclass,java::lang::ClassLoader*);
 215 void _Jv_UnregisterInitiatingLoader (jclass,java::lang::ClassLoader*);
 216 void _Jv_UnregisterClass (jclass);
 217 jclass _Jv_FindClass (_Jv_Utf8Const *name,
 218                       java::lang::ClassLoader *loader);
 219 jclass _Jv_FindClassInCache (_Jv_Utf8Const *name);
 220 jclass _Jv_PopClass (void);
 221 void _Jv_PushClass (jclass k);
 222 void _Jv_NewArrayClass (jclass element,
 223                         java::lang::ClassLoader *loader,
 224                         _Jv_VTable *array_vtable = 0);
 225 jclass _Jv_NewClass (_Jv_Utf8Const *name, jclass superclass,
 226                      java::lang::ClassLoader *loader);
 227 void _Jv_InitNewClassFields (jclass klass);
 228
 229 // Friend functions and classes in prims.cc
 230 void _Jv_InitPrimClass (jclass, char *, char, int);
 231 jstring _Jv_GetMethodString (jclass, _Jv_Method *, jclass = NULL);
 232
 233 jboolean _Jv_CheckAccess (jclass self_klass, jclass other_klass,
 234                           jint flags);
 235 jclass _Jv_GetArrayClass (jclass klass, java::lang::ClassLoader *loader);
 236
 237 #ifdef INTERPRETER
 238 jboolean _Jv_IsInterpretedClass (jclass);
 239 void _Jv_InitField (jobject, jclass, int);
 240
 241 class _Jv_ClassReader;
 242 class _Jv_InterpClass;
 243 class _Jv_InterpMethod;
 244 #endif
 245
 246 class _Jv_BytecodeVerifier;
 247 class gnu::gcj::runtime::StackTrace;
 248 class java::io::VMObjectStreamClass;
 249
 250 void _Jv_sharedlib_register_hook (jclass klass);
 251
 252
 253 class java::lang::Class : public java::lang::Object
 254 {
 255 public:
 256   static jclass forName (jstring className, jboolean initialize,
 257                          java::lang::ClassLoader *loader);
 258   static jclass forName (jstring className);
 259   JArray<jclass> *getClasses (void);
 260
 261   java::lang::ClassLoader *getClassLoader (void);
 262
 263   // This is an internal method that circumvents the usual security
 264   // checks when getting the class loader.
 265   java::lang::ClassLoader *getClassLoaderInternal (void)
 266   {
 267     return loader;
 268   }
 269
 270   java::lang::reflect::Constructor *getConstructor (JArray<jclass> *);
 271   JArray<java::lang::reflect::Constructor *> *getConstructors (void);
 272   java::lang::reflect::Constructor *getDeclaredConstructor (JArray<jclass> *);
 273   JArray<java::lang::reflect::Constructor *> *getDeclaredConstructors (void);
 274   java::lang::reflect::Field *getDeclaredField (jstring);
 275   JArray<java::lang::reflect::Field *> *getDeclaredFields ();
 276   JArray<java::lang::reflect::Field *> *getDeclaredFields (jboolean);
 277   java::lang::reflect::Method *getDeclaredMethod (jstring, JArray<jclass> *);
 278   JArray<java::lang::reflect::Method *> *getDeclaredMethods (void);
 279
 280   JArray<jclass> *getDeclaredClasses (void);
 281   jclass getDeclaringClass (void);
 282
 283   java::lang::reflect::Field *getField (jstring);
 284 private:
 285   JArray<java::lang::reflect::Field *> internalGetFields ();
 286   JArray<java::lang::reflect::Constructor *> *_getConstructors (jboolean);
 287   java::lang::reflect::Field *getField (jstring, jint);
 288   jint _getMethods (JArray<java::lang::reflect::Method *> *result,
 289                     jint offset);
 290   java::lang::reflect::Field *getPrivateField (jstring);
 291   java::lang::reflect::Method *getPrivateMethod (jstring, JArray<jclass> *);
 292   java::security::ProtectionDomain *getProtectionDomain0 ();
 293
 294   java::lang::reflect::Method *_getMethod (jstring, JArray<jclass> *);
 295   java::lang::reflect::Method *_getDeclaredMethod (jstring, JArray<jclass> *);
 296
 297 public:
 298   JArray<java::lang::reflect::Field *> *getFields (void);
 299
 300   JArray<jclass> *getInterfaces (void);
 301
 302   void getSignature (java::lang::StringBuffer *buffer);
 303   static jstring getSignature (JArray<jclass> *, jboolean is_constructor);
 304   JArray<java::lang::reflect::Method *> *getMethods (void);
 305
 306   inline jint getModifiers (void)
 307   {
 308     return accflags & java::lang::reflect::Modifier::ALL_FLAGS;
 309   }
 310
 311   jstring getName (void);
 312
 313   java::net::URL        *getResource (jstring resourceName);
 314   java::io::InputStream *getResourceAsStream (jstring resourceName);
 315   JArray<jobject> *getSigners (void);
 316   void setSigners(JArray<jobject> *);
 317
 318   inline jclass getSuperclass (void)
 319   {
 320     return superclass;
 321   }
 322
 323   inline jclass getInterface (jint n)
 324   {
 325     return interfaces[n];
 326   }
 327
 328   inline jboolean isArray (void)
 329     {
 330       return name->first() == '[';
 331     }
 332
 333   inline jclass getComponentType (void)
 334     {
 335       return isArray () ? (* (jclass *) &methods) : 0;
 336     }
 337
 338   jboolean isAssignableFrom (jclass cls);
 339   jboolean isInstance (jobject obj);
 340
 341   inline jboolean isInterface (void)
 342   {
 343     return (accflags & java::lang::reflect::Modifier::INTERFACE) != 0;
 344   }
 345
 346   inline jboolean isPrimitive (void)
 347     {
 348       return vtable == JV_PRIMITIVE_VTABLE;
 349     }
 350
 351   jobject newInstance (void);
 352   java::security::ProtectionDomain *getProtectionDomain (void);
 353   java::lang::Package *getPackage (void);
 354   jstring toString (void);
 355   jboolean desiredAssertionStatus (void);
 356
 357   // FIXME: this probably shouldn't be public.
 358   jint size (void)
 359   {
 360     return size_in_bytes;
 361   }
 362
 363   // The index of the first method we declare ourself (as opposed to
 364   // inheriting).
 365   inline jint firstMethodIndex (void)
 366   {
 367     return vtable_method_count - method_count;
 368   }
 369
 370   // finalization
 371   void finalize ();
 372
 373   // This constructor is used to create Class object for the primitive
 374   // types. See prims.cc.
 375   Class ();
 376
 377   static java::lang::Class class$;
 378
 379 private:
 380
 381   void memberAccessCheck (jint flags);
 382
 383   void initializeClass (void);
 384
 385   static jstring getPackagePortion (jstring);
 386
 387   void set_state (jint nstate)
 388   {
 389     state = nstate;
 390     notifyAll ();
 391   }
 392
 393   // Friend functions implemented in natClass.cc.
 394   friend _Jv_Method *::_Jv_GetMethodLocal (jclass klass, _Jv_Utf8Const *name,
 395                                            _Jv_Utf8Const *signature);
 396   friend jboolean (::_Jv_IsAssignableFrom) (jclass, jclass);
 397   friend jboolean (::_Jv_IsAssignableFromSlow) (jclass, jclass);
 398   friend jboolean (::_Jv_InterfaceAssignableFrom) (jclass, jclass);
 399   friend void *::_Jv_LookupInterfaceMethodIdx (jclass klass, jclass iface,
 400                                                int method_idx);
 401
 402   friend void ::_Jv_InitClass (jclass klass);
 403
 404   friend _Jv_Method* ::_Jv_LookupDeclaredMethod (jclass, _Jv_Utf8Const *,
 405                                                  _Jv_Utf8Const*, jclass *);
 406   friend jfieldID (::JvGetFirstInstanceField) (jclass);
 407   friend jint (::JvNumInstanceFields) (jclass);
 408   friend jfieldID (::JvGetFirstStaticField) (jclass);
 409   friend jint (::JvNumStaticFields) (jclass);
 410
 411   friend jobject (::_Jv_AllocObject) (jclass);
 412   friend void *::_Jv_AllocObj (jint, jclass);
 413   friend void *::_Jv_AllocPtrFreeObj (jint, jclass);
 414   friend void *::_Jv_AllocArray (jint, jclass);
 415
 416   friend jobject (::_Jv_JNI_ToReflectedField) (_Jv_JNIEnv *, jclass, jfieldID,
 417                                                jboolean);
 418   friend jobject (::_Jv_JNI_ToReflectedMethod) (_Jv_JNIEnv *, jclass, jmethodID,
 419                                                 jboolean);
 420   friend jfieldID (::_Jv_FromReflectedField) (java::lang::reflect::Field *);
 421
 422   friend jmethodID (::_Jv_FromReflectedMethod) (java::lang::reflect::Method *);
 423   friend jmethodID (::_Jv_FromReflectedConstructor) (java::lang::reflect::Constructor *);
 424   friend jint (::JvNumMethods) (jclass);
 425   friend jmethodID (::JvGetFirstMethod) (jclass);
 426
 427   // Friends classes and functions to implement the ClassLoader
 428   friend class java::lang::ClassLoader;
 429   friend class java::lang::VMClassLoader;
 430
 431   friend class java::io::ObjectOutputStream;
 432   friend class java::io::ObjectInputStream;
 433   friend class java::io::ObjectStreamClass;
 434
 435   friend void ::_Jv_RegisterClasses (const jclass *classes);
 436   friend void ::_Jv_RegisterClasses_Counted (const jclass *classes,
 437                                              size_t count);
 438   friend void ::_Jv_RegisterClassHookDefault (jclass klass);
 439   friend void ::_Jv_RegisterInitiatingLoader (jclass,java::lang::ClassLoader*);
 440   friend void ::_Jv_UnregisterInitiatingLoader (jclass,java::lang::ClassLoader*);
 441   friend void ::_Jv_UnregisterClass (jclass);
 442   friend jclass (::_Jv_FindClass) (_Jv_Utf8Const *name,
 443                                    java::lang::ClassLoader *loader);
 444   friend jclass (::_Jv_FindClassInCache) (_Jv_Utf8Const *name);
 445   friend jclass (::_Jv_PopClass) (void);
 446   friend void ::_Jv_PushClass (jclass k);
 447   friend void ::_Jv_NewArrayClass (jclass element,
 448                                    java::lang::ClassLoader *loader,
 449                                    _Jv_VTable *array_vtable);
 450   friend jclass (::_Jv_NewClass) (_Jv_Utf8Const *name, jclass superclass,
 451                                   java::lang::ClassLoader *loader);
 452   friend void ::_Jv_InitNewClassFields (jclass klass);
 453
 454   // in prims.cc
 455   friend void ::_Jv_InitPrimClass (jclass, char *, char, int);
 456
 457   friend jstring (::_Jv_GetMethodString) (jclass, _Jv_Method *, jclass);
 458
 459   friend jboolean (::_Jv_CheckAccess) (jclass self_klass, jclass other_klass,
 460                                    jint flags);
 461
 462   friend bool (::_Jv_getInterfaceMethod) (jclass, jclass&, int&,
 463                                           const _Jv_Utf8Const*,
 464                                           const _Jv_Utf8Const*);
 465
 466   friend jclass (::_Jv_GetArrayClass) (jclass klass,
 467                                        java::lang::ClassLoader *loader);
 468
 469 #ifdef INTERPRETER
 470   friend jboolean (::_Jv_IsInterpretedClass) (jclass);
 471   friend void ::_Jv_InitField (jobject, jclass, int);
 472
 473   friend class ::_Jv_ClassReader;
 474   friend class ::_Jv_InterpClass;
 475   friend class ::_Jv_InterpMethod;
 476 #endif
 477
 478 #ifdef JV_MARKOBJ_DECL
 479   friend JV_MARKOBJ_DECL;
 480 #endif
 481
 482   friend class ::_Jv_BytecodeVerifier;
 483   friend class gnu::gcj::runtime::StackTrace;
 484   friend class java::io::VMObjectStreamClass;
 485
 486   friend class ::_Jv_Linker;
 487   friend class ::_Jv_ExecutionEngine;
 488   friend class ::_Jv_CompiledEngine;
 489   friend class ::_Jv_InterpreterEngine;
 490
 491   friend void ::_Jv_sharedlib_register_hook (jclass klass);
 492
 493   // Chain for class pool.  This also doubles as the ABI version
 494   // number.  It is only used for this purpose at class registration
 495   // time, and only for precompiled classes.
 496   jclass next_or_version;
 497   // Name of class.
 498   _Jv_Utf8Const *name;
 499   // Access flags for class.
 500   _Jv_ushort accflags;
 501   // The superclass, or null for Object.
 502   jclass superclass;
 503   // Class constants.
 504   _Jv_Constants constants;
 505   // Methods.  If this is an array class, then this field holds a
 506   // pointer to the element type.
 507   _Jv_Method *methods;
 508   // Number of methods.  If this class is primitive, this holds the
 509   // character used to represent this type in a signature.
 510   jshort method_count;
 511   // Number of methods in the vtable.
 512   jshort vtable_method_count;
 513   // The fields.
 514   _Jv_Field *fields;
 515   // Size of instance fields, in bytes.
 516   jint size_in_bytes;
 517   // Total number of fields (instance and static).
 518   jshort field_count;
 519   // Number of static fields.
 520   jshort static_field_count;
 521   // The vtbl for all objects of this class.
 522   _Jv_VTable *vtable;
 523   // Virtual method offset table.
 524   _Jv_OffsetTable *otable;
 525   // Offset table symbols.
 526   _Jv_MethodSymbol *otable_syms;
 527   // Address table
 528   _Jv_AddressTable *atable;
 529   _Jv_MethodSymbol *atable_syms;
 530   // Interface table
 531   _Jv_AddressTable *itable;
 532   _Jv_MethodSymbol *itable_syms;
 533   _Jv_CatchClass *catch_classes;
 534   // Interfaces implemented by this class.
 535   jclass *interfaces;
 536   // The class loader for this class.
 537   java::lang::ClassLoader *loader;
 538   // Number of interfaces.
 539   jshort interface_count;
 540   // State of this class.
 541   jbyte state;
 542   // The thread which has locked this class.  Used during class
 543   // initialization.
 544   java::lang::Thread *thread;
 545   // How many levels of "extends" this class is removed from Object.
 546   jshort depth;
 547   // Vector of this class's superclasses, ordered by decreasing depth.
 548   jclass *ancestors;
 549   // Interface Dispatch Table.
 550   _Jv_IDispatchTable *idt;
 551   // Pointer to the class that represents an array of this class.
 552   jclass arrayclass;
 553   // Security Domain to which this class belongs (or null).
 554   java::security::ProtectionDomain *protectionDomain;
 555   // Pointer to the type assertion table for this class.
 556   _Jv_TypeAssertion *assertion_table;
 557   // Signers of this class (or null).
 558   JArray<jobject> *hack_signers;
 559   // Used by Jv_PopClass and _Jv_PushClass to communicate with StackTrace.
 560   jclass chain;
 561   // Additional data, specific to the generator (JIT, native,
 562   // interpreter) of this class.
 563   void *aux_info;
 564   // Execution engine.
 565   _Jv_ExecutionEngine *engine;
 566 };
 567
 568 // Inline functions that are friends of java::lang::Class
 569
 570 inline void _Jv_InitClass (jclass klass)
 571 {
 572   if (__builtin_expect (klass->state == JV_STATE_DONE, true))
 573     return;
 574   klass->initializeClass ();
 575 }
 576
 577 // Return array class corresponding to element type KLASS, creating it if
 578 // necessary.
 579 inline jclass
 580 _Jv_GetArrayClass (jclass klass, java::lang::ClassLoader *loader)
 581 {
 582   extern void _Jv_NewArrayClass (jclass element,
 583                                  java::lang::ClassLoader *loader,
 584                                  _Jv_VTable *array_vtable = 0);
 585   if (__builtin_expect (!klass->arrayclass, false))
 586     _Jv_NewArrayClass (klass, loader);
 587   return klass->arrayclass;
 588 }
 589
 590 #endif /* __JAVA_LANG_CLASS_H__ */