1 /* 2 ****************************************************************************** 3 * 4 * Copyright (C) 2002-2009, International Business Machines 5 * Corporation and others. All Rights Reserved. 6 * 7 ****************************************************************************** 8 * file name: uobject.h 9 * encoding: US-ASCII 10 * tab size: 8 (not used) 11 * indentation:4 12 * 13 * created on: 2002jun26 14 * created by: Markus W. Scherer 15 */ 16 17 #ifndef __UOBJECT_H__ 18 #define __UOBJECT_H__ 19 20 #include "unicode/utypes.h" 21 22 U_NAMESPACE_BEGIN 23 24 /** 25 * \file 26 * \brief C++ API: Common ICU base class UObject. 27 */ 28 29 /** U_OVERRIDE_CXX_ALLOCATION - Define this to override operator new and 30 * delete in UMemory. Enabled by default for ICU. 31 * 32 * Enabling forces all allocation of ICU object types to use ICU's 33 * memory allocation. On Windows, this allows the ICU DLL to be used by 34 * applications that statically link the C Runtime library, meaning that 35 * the app and ICU will be using different heaps. 36 * 37 * @stable ICU 2.2 38 */ 39 #ifndef U_OVERRIDE_CXX_ALLOCATION 40 #define U_OVERRIDE_CXX_ALLOCATION 1 41 #endif 42 43 /** 44 * \def U_HAVE_PLACEMENT_NEW 45 * Define this to define the placement new and 46 * delete in UMemory for STL. 47 * 48 * @stable ICU 2.6 49 */ 50 #ifndef U_HAVE_PLACEMENT_NEW 51 #define U_HAVE_PLACEMENT_NEW 1 52 #endif 53 54 55 /** 56 * \def U_HAVE_DEBUG_LOCATION_NEW 57 * Define this to define the MFC debug 58 * version of the operator new. 59 * 60 * @stable ICU 3.4 61 */ 62 #ifndef U_HAVE_DEBUG_LOCATION_NEW 63 #define U_HAVE_DEBUG_LOCATION_NEW 0 64 #endif 65 66 /** 67 * \def U_NO_THROW 68 * Define this to define the throw() specification so 69 certain functions do not throw any exceptions 70 * 71 * UMemory operator new methods should have the throw() specification 72 * appended to them, so that the compiler adds the additional NULL check 73 * before calling constructors. Without, if <code>operator new</code> returns NULL the 74 * constructor is still called, and if the constructor references member 75 * data, (which it typically does), the result is a segmentation violation. 76 * 77 * @draft ICU 4.2 78 */ 79 #ifndef U_NO_THROW 80 #define U_NO_THROW throw() 81 #endif 82 83 /** 84 * UMemory is the common ICU base class. 85 * All other ICU C++ classes are derived from UMemory (starting with ICU 2.4). 86 * 87 * This is primarily to make it possible and simple to override the 88 * C++ memory management by adding new/delete operators to this base class. 89 * 90 * To override ALL ICU memory management, including that from plain C code, 91 * replace the allocation functions declared in cmemory.h 92 * 93 * UMemory does not contain any virtual functions. 94 * Common "boilerplate" functions are defined in UObject. 95 * 96 * @stable ICU 2.4 97 */ 98 class U_COMMON_API UMemory { 99 public: 100 101 /* test versions for debugging shaper heap memory problems */ 102 #ifdef SHAPER_MEMORY_DEBUG 103 static void * NewArray(int size, int count); 104 static void * GrowArray(void * array, int newSize ); 105 static void FreeArray(void * array ); 106 #endif 107 108 #if U_OVERRIDE_CXX_ALLOCATION 109 /** 110 * Override for ICU4C C++ memory management. 111 * simple, non-class types are allocated using the macros in common/cmemory.h 112 * (uprv_malloc(), uprv_free(), uprv_realloc()); 113 * they or something else could be used here to implement C++ new/delete 114 * for ICU4C C++ classes 115 * @stable ICU 2.4 116 */ 117 static void * U_EXPORT2 operator new(size_t size) U_NO_THROW; 118 119 /** 120 * Override for ICU4C C++ memory management. 121 * See new(). 122 * @stable ICU 2.4 123 */ 124 static void * U_EXPORT2 operator new[](size_t size) U_NO_THROW; 125 126 /** 127 * Override for ICU4C C++ memory management. 128 * simple, non-class types are allocated using the macros in common/cmemory.h 129 * (uprv_malloc(), uprv_free(), uprv_realloc()); 130 * they or something else could be used here to implement C++ new/delete 131 * for ICU4C C++ classes 132 * @stable ICU 2.4 133 */ 134 static void U_EXPORT2 operator delete(void *p) U_NO_THROW; 135 136 /** 137 * Override for ICU4C C++ memory management. 138 * See delete(). 139 * @stable ICU 2.4 140 */ 141 static void U_EXPORT2 operator delete[](void *p) U_NO_THROW; 142 143 #if U_HAVE_PLACEMENT_NEW 144 /** 145 * Override for ICU4C C++ memory management for STL. 146 * See new(). 147 * @stable ICU 2.6 148 */ 149 static inline void * U_EXPORT2 operator new(size_t, void *ptr) U_NO_THROW { return ptr; } 150 151 /** 152 * Override for ICU4C C++ memory management for STL. 153 * See delete(). 154 * @stable ICU 2.6 155 */ 156 static inline void U_EXPORT2 operator delete(void *, void *) U_NO_THROW {} 157 #endif /* U_HAVE_PLACEMENT_NEW */ 158 #if U_HAVE_DEBUG_LOCATION_NEW 159 /** 160 * This method overrides the MFC debug version of the operator new 161 * 162 * @param size The requested memory size 163 * @param file The file where the allocation was requested 164 * @param line The line where the allocation was requested 165 */ 166 static void * U_EXPORT2 operator new(size_t size, const char* file, int line) U_NO_THROW; 167 /** 168 * This method provides a matching delete for the MFC debug new 169 * 170 * @param p The pointer to the allocated memory 171 * @param file The file where the allocation was requested 172 * @param line The line where the allocation was requested 173 */ 174 static void U_EXPORT2 operator delete(void* p, const char* file, int line) U_NO_THROW; 175 #endif /* U_HAVE_DEBUG_LOCATION_NEW */ 176 #endif /* U_OVERRIDE_CXX_ALLOCATION */ 177 178 /* 179 * Assignment operator not declared. The compiler will provide one 180 * which does nothing since this class does not contain any data members. 181 * API/code coverage may show the assignment operator as present and 182 * untested - ignore. 183 * Subclasses need this assignment operator if they use compiler-provided 184 * assignment operators of their own. An alternative to not declaring one 185 * here would be to declare and empty-implement a protected or public one. 186 UMemory &UMemory::operator=(const UMemory &); 187 */ 188 }; 189 190 /** 191 * UObject is the common ICU "boilerplate" class. 192 * UObject inherits UMemory (starting with ICU 2.4), 193 * and all other public ICU C++ classes 194 * are derived from UObject (starting with ICU 2.2). 195 * 196 * UObject contains common virtual functions like for ICU's "poor man's RTTI". 197 * It does not contain default implementations of virtual methods 198 * like getDynamicClassID to allow derived classes such as Format 199 * to declare these as pure virtual. 200 * 201 * The clone() function is not available in UObject because it is not 202 * implemented by all ICU classes. 203 * Many ICU services provide a clone() function for their class trees, 204 * defined on the service's C++ base class, and all subclasses within that 205 * service class tree return a pointer to the service base class 206 * (which itself is a subclass of UObject). 207 * This is because some compilers do not support covariant (same-as-this) 208 * return types; cast to the appropriate subclass if necessary. 209 * 210 * @stable ICU 2.2 211 */ 212 class U_COMMON_API UObject : public UMemory { 213 public: 214 /** 215 * Destructor. 216 * 217 * @stable ICU 2.2 218 */ 219 virtual ~UObject(); 220 221 /** 222 * ICU4C "poor man's RTTI", returns a UClassID for the actual ICU class. 223 * 224 * @stable ICU 2.2 225 */ 226 virtual UClassID getDynamicClassID() const = 0; 227 228 protected: 229 // the following functions are protected to prevent instantiation and 230 // direct use of UObject itself 231 232 // default constructor 233 // commented out because UObject is abstract (see getDynamicClassID) 234 // inline UObject() {} 235 236 // copy constructor 237 // commented out because UObject is abstract (see getDynamicClassID) 238 // inline UObject(const UObject &other) {} 239 240 #if 0 241 // TODO Sometime in the future. Implement operator==(). 242 // (This comment inserted in 2.2) 243 // some or all of the following "boilerplate" functions may be made public 244 // in a future ICU4C release when all subclasses implement them 245 246 // assignment operator 247 // (not virtual, see "Taligent's Guide to Designing Programs" pp.73..74) 248 // commented out because the implementation is the same as a compiler's default 249 // UObject &operator=(const UObject &other) { return *this; } 250 251 // comparison operators 252 virtual inline UBool operator==(const UObject &other) const { return this==&other; } 253 inline UBool operator!=(const UObject &other) const { return !operator==(other); } 254 255 // clone() commented out from the base class: 256 // some compilers do not support co-variant return types 257 // (i.e., subclasses would have to return UObject * as well, instead of SubClass *) 258 // see also UObject class documentation. 259 // virtual UObject *clone() const; 260 #endif 261 262 /* 263 * Assignment operator not declared. The compiler will provide one 264 * which does nothing since this class does not contain any data members. 265 * API/code coverage may show the assignment operator as present and 266 * untested - ignore. 267 * Subclasses need this assignment operator if they use compiler-provided 268 * assignment operators of their own. An alternative to not declaring one 269 * here would be to declare and empty-implement a protected or public one. 270 UObject &UObject::operator=(const UObject &); 271 */ 272 273 // Future implementation for RTTI that support subtyping. [alan] 274 // 275 // public: 276 // /** 277 // * @internal 278 // */ 279 // static UClassID getStaticClassID(); 280 // 281 // /** 282 // * @internal 283 // */ 284 // UBool instanceOf(UClassID type) const; 285 }; 286 287 /** 288 * This is a simple macro to add ICU RTTI to an ICU object implementation. 289 * This does not go into the header. This should only be used in *.cpp files. 290 * 291 * @param myClass The name of the class that needs RTTI defined. 292 * @internal 293 */ 294 #define UOBJECT_DEFINE_RTTI_IMPLEMENTATION(myClass) \ 295 UClassID U_EXPORT2 myClass::getStaticClassID() { \ 296 static char classID = 0; \ 297 return (UClassID)&classID; \ 298 } \ 299 UClassID myClass::getDynamicClassID() const \ 300 { return myClass::getStaticClassID(); } 301 302 303 /** 304 * This macro adds ICU RTTI to an ICU abstract class implementation. 305 * This macro should be invoked in *.cpp files. The corresponding 306 * header should declare getStaticClassID. 307 * 308 * @param myClass The name of the class that needs RTTI defined. 309 * @internal 310 */ 311 #define UOBJECT_DEFINE_ABSTRACT_RTTI_IMPLEMENTATION(myClass) \ 312 UClassID U_EXPORT2 myClass::getStaticClassID() { \ 313 static char classID = 0; \ 314 return (UClassID)&classID; \ 315 } 316 317 // /** 318 // * This macro adds ICU RTTI to an ICU concrete class implementation. 319 // * This macro should be invoked in *.cpp files. The corresponding 320 // * header should declare getDynamicClassID and getStaticClassID. 321 // * 322 // * @param myClass The name of the class that needs RTTI defined. 323 // * @param myParent The name of the myClass's parent. 324 // * @internal 325 // */ 326 /*#define UOBJECT_DEFINE_RTTI_IMPLEMENTATION(myClass, myParent) \ 327 UOBJECT_DEFINE_ABSTRACT_RTTI_IMPLEMENTATION(myClass, myParent) \ 328 UClassID myClass::getDynamicClassID() const { \ 329 return myClass::getStaticClassID(); \ 330 } 331 */ 332 333 334 U_NAMESPACE_END 335 336 #endif 337