/* ****************************************************************************** * * Copyright (C) 2002-2007, International Business Machines * Corporation and others. All Rights Reserved. * ****************************************************************************** * file name: uobject.h * encoding: US-ASCII * tab size: 8 (not used) * indentation:4 * * created on: 2002jun26 * created by: Markus W. Scherer */ #ifndef __UOBJECT_H__ #define __UOBJECT_H__ #include "unicode/utypes.h" U_NAMESPACE_BEGIN /** * \file * \brief C++ API: Common ICU base class UObject. */ /** U_OVERRIDE_CXX_ALLOCATION - Define this to override operator new and * delete in UMemory. Enabled by default for ICU. * * Enabling forces all allocation of ICU object types to use ICU's * memory allocation. On Windows, this allows the ICU DLL to be used by * applications that statically link the C Runtime library, meaning that * the app and ICU will be using different heaps. * * @stable ICU 2.2 */ #ifndef U_OVERRIDE_CXX_ALLOCATION #define U_OVERRIDE_CXX_ALLOCATION 1 #endif /** U_HAVE_PLACEMENT_NEW - Define this to define the placement new and * delete in UMemory for STL. * * @stable ICU 2.6 */ #ifndef U_HAVE_PLACEMENT_NEW #define U_HAVE_PLACEMENT_NEW 1 #endif /** U_HAVE_DEBUG_LOCATION_NEW - Define this to define the MFC debug * version of the operator new. * * @stable ICU 3.4 */ #ifndef U_HAVE_DEBUG_LOCATION_NEW #define U_HAVE_DEBUG_LOCATION_NEW 0 #endif /** * UMemory is the common ICU base class. * All other ICU C++ classes are derived from UMemory (starting with ICU 2.4). * * This is primarily to make it possible and simple to override the * C++ memory management by adding new/delete operators to this base class. * * To override ALL ICU memory management, including that from plain C code, * replace the allocation functions declared in cmemory.h * * UMemory does not contain any virtual functions. * Common "boilerplate" functions are defined in UObject. * * @stable ICU 2.4 */ class U_COMMON_API UMemory { public: #if U_OVERRIDE_CXX_ALLOCATION /** * Override for ICU4C C++ memory management. * simple, non-class types are allocated using the macros in common/cmemory.h * (uprv_malloc(), uprv_free(), uprv_realloc()); * they or something else could be used here to implement C++ new/delete * for ICU4C C++ classes * @stable ICU 2.4 */ static void * U_EXPORT2 operator new(size_t size); /** * Override for ICU4C C++ memory management. * See new(). * @stable ICU 2.4 */ static void * U_EXPORT2 operator new[](size_t size); /** * Override for ICU4C C++ memory management. * simple, non-class types are allocated using the macros in common/cmemory.h * (uprv_malloc(), uprv_free(), uprv_realloc()); * they or something else could be used here to implement C++ new/delete * for ICU4C C++ classes * @stable ICU 2.4 */ static void U_EXPORT2 operator delete(void *p); /** * Override for ICU4C C++ memory management. * See delete(). * @stable ICU 2.4 */ static void U_EXPORT2 operator delete[](void *p); #if U_HAVE_PLACEMENT_NEW /** * Override for ICU4C C++ memory management for STL. * See new(). * @stable ICU 2.6 */ static inline void * U_EXPORT2 operator new(size_t, void *ptr) { return ptr; } /** * Override for ICU4C C++ memory management for STL. * See delete(). * @stable ICU 2.6 */ static inline void U_EXPORT2 operator delete(void *, void *) {} #endif /* U_HAVE_PLACEMENT_NEW */ #if U_HAVE_DEBUG_LOCATION_NEW /** * This method overrides the MFC debug version of the operator new * * @param size The requested memory size * @param file The file where the allocation was requested * @param line The line where the allocation was requested */ static void * U_EXPORT2 operator new(size_t size, const char* file, int line); /** * This method provides a matching delete for the MFC debug new * * @param p The pointer to the allocated memory * @param file The file where the allocation was requested * @param line The line where the allocation was requested */ static void U_EXPORT2 operator delete(void* p, const char* file, int line); #endif /* U_HAVE_DEBUG_LOCATION_NEW */ #endif /* U_OVERRIDE_CXX_ALLOCATION */ /* * Assignment operator not declared. The compiler will provide one * which does nothing since this class does not contain any data members. * API/code coverage may show the assignment operator as present and * untested - ignore. * Subclasses need this assignment operator if they use compiler-provided * assignment operators of their own. An alternative to not declaring one * here would be to declare and empty-implement a protected or public one. UMemory &UMemory::operator=(const UMemory &); */ }; /** * UObject is the common ICU "boilerplate" class. * UObject inherits UMemory (starting with ICU 2.4), * and all other public ICU C++ classes * are derived from UObject (starting with ICU 2.2). * * UObject contains common virtual functions like for ICU's "poor man's RTTI". * It does not contain default implementations of virtual methods * like getDynamicClassID to allow derived classes such as Format * to declare these as pure virtual. * * The clone() function is not available in UObject because it is not * implemented by all ICU classes. * Many ICU services provide a clone() function for their class trees, * defined on the service's C++ base class, and all subclasses within that * service class tree return a pointer to the service base class * (which itself is a subclass of UObject). * This is because some compilers do not support covariant (same-as-this) * return types; cast to the appropriate subclass if necessary. * * @stable ICU 2.2 */ class U_COMMON_API UObject : public UMemory { public: /** * Destructor. * * @stable ICU 2.2 */ virtual ~UObject(); /** * ICU4C "poor man's RTTI", returns a UClassID for the actual ICU class. * * @stable ICU 2.2 */ virtual UClassID getDynamicClassID() const = 0; protected: // the following functions are protected to prevent instantiation and // direct use of UObject itself // default constructor // commented out because UObject is abstract (see getDynamicClassID) // inline UObject() {} // copy constructor // commented out because UObject is abstract (see getDynamicClassID) // inline UObject(const UObject &other) {} #if 0 // TODO Sometime in the future. Implement operator==(). // (This comment inserted in 2.2) // some or all of the following "boilerplate" functions may be made public // in a future ICU4C release when all subclasses implement them // assignment operator // (not virtual, see "Taligent's Guide to Designing Programs" pp.73..74) // commented out because the implementation is the same as a compiler's default // UObject &operator=(const UObject &other) { return *this; } // comparison operators virtual inline UBool operator==(const UObject &other) const { return this==&other; } inline UBool operator!=(const UObject &other) const { return !operator==(other); } // clone() commented out from the base class: // some compilers do not support co-variant return types // (i.e., subclasses would have to return UObject * as well, instead of SubClass *) // see also UObject class documentation. // virtual UObject *clone() const; #endif /* * Assignment operator not declared. The compiler will provide one * which does nothing since this class does not contain any data members. * API/code coverage may show the assignment operator as present and * untested - ignore. * Subclasses need this assignment operator if they use compiler-provided * assignment operators of their own. An alternative to not declaring one * here would be to declare and empty-implement a protected or public one. UObject &UObject::operator=(const UObject &); */ // Future implementation for RTTI that support subtyping. [alan] // // public: // /** // * @internal // */ // static UClassID getStaticClassID(); // // /** // * @internal // */ // UBool instanceOf(UClassID type) const; }; /** * This is a simple macro to add ICU RTTI to an ICU object implementation. * This does not go into the header. This should only be used in *.cpp files. * * @param myClass The name of the class that needs RTTI defined. * @internal */ #define UOBJECT_DEFINE_RTTI_IMPLEMENTATION(myClass) \ UClassID U_EXPORT2 myClass::getStaticClassID() { \ static char classID = 0; \ return (UClassID)&classID; \ } \ UClassID myClass::getDynamicClassID() const \ { return myClass::getStaticClassID(); } /** * This macro adds ICU RTTI to an ICU abstract class implementation. * This macro should be invoked in *.cpp files. The corresponding * header should declare getStaticClassID. * * @param myClass The name of the class that needs RTTI defined. * @internal */ #define UOBJECT_DEFINE_ABSTRACT_RTTI_IMPLEMENTATION(myClass) \ UClassID U_EXPORT2 myClass::getStaticClassID() { \ static char classID = 0; \ return (UClassID)&classID; \ } // /** // * This macro adds ICU RTTI to an ICU concrete class implementation. // * This macro should be invoked in *.cpp files. The corresponding // * header should declare getDynamicClassID and getStaticClassID. // * // * @param myClass The name of the class that needs RTTI defined. // * @param myParent The name of the myClass's parent. // * @internal // */ /*#define UOBJECT_DEFINE_RTTI_IMPLEMENTATION(myClass, myParent) \ UOBJECT_DEFINE_ABSTRACT_RTTI_IMPLEMENTATION(myClass, myParent) \ UClassID myClass::getDynamicClassID() const { \ return myClass::getStaticClassID(); \ } */ U_NAMESPACE_END #endif