// © 2016 and later: Unicode, Inc. and others. // License & terms of use: http://www.unicode.org/copyright.html /* ********************************************************************** * Copyright (C) 1999-2016, International Business Machines * Corporation and others. All Rights Reserved. ********************************************************************** * Date Name Description * 10/22/99 alan Creation. This is an internal header. * It should not be exported. ********************************************************************** */ #ifndef UVECTOR_H #define UVECTOR_H #include "unicode/utypes.h" #include "unicode/uobject.h" #include "cmemory.h" #include "uarrsort.h" #include "uelement.h" U_NAMESPACE_BEGIN /** * Ultralightweight C++ implementation of a `void*` vector * that is (mostly) compatible with java.util.Vector. * * This is a very simple implementation, written to satisfy an * immediate porting need. As such, it is not completely fleshed out, * and it aims for simplicity and conformity. Nonetheless, it serves * its purpose (porting code from java that uses java.util.Vector) * well, and it could be easily made into a more robust vector class. * * *Design notes* * * There is index bounds checking, but little is done about it. If * indices are out of bounds, either nothing happens, or zero is * returned. We *do* avoid indexing off into the weeds. * * Since we don't have garbage collection, UVector was given the * option to *own* its contents. To employ this, set a deleter * function. The deleter is called on a `void *` pointer when that * pointer is released by the vector, either when the vector itself is * destructed, or when a call to `setElementAt()` overwrites an element, * or when a call to remove()` or one of its variants explicitly * removes an element. If no deleter is set, or the deleter is set to * zero, then it is assumed that the caller will delete elements as * needed. * * *Error Handling* Functions that can fail, from out of memory conditions * for example, include a UErrorCode parameter. Any function called * with an error code already indicating a failure will not modify the * vector in any way. * * For vectors that have a deleter function, any failure in inserting * an element into the vector will instead delete the element that * could not be adopted. This simplifies object ownership * management around calls to `addElement()` and `insertElementAt()`; * error or no, the function always takes ownership of an incoming object * from the caller. * * In order to implement methods such as `contains()` and `indexOf()`, * UVector needs a way to compare objects for equality. To do so, it * uses a comparison function, or "comparer." If the comparer is not * set, or is set to zero, then all such methods will act as if the * vector contains no element. That is, indexOf() will always return * -1, contains() will always return false, etc. * * <p><b>To do</b> * * <p>Improve the handling of index out of bounds errors. * * @author Alan Liu */ class U_COMMON_API UVector : public UObject { // NOTE: UVector uses the UElement (union of void* and int32_t) as // its basic storage type. It uses UElementsAreEqual as its // comparison function. It uses UObjectDeleter as its deleter // function. This allows sharing of support functions with UHashtable. private: int32_t count = 0; int32_t capacity = 0; UElement* elements = nullptr; UObjectDeleter *deleter = nullptr; UElementsAreEqual *comparer = nullptr; public: UVector(UErrorCode &status); UVector(int32_t initialCapacity, UErrorCode &status); UVector(UObjectDeleter *d, UElementsAreEqual *c, UErrorCode &status); UVector(UObjectDeleter *d, UElementsAreEqual *c, int32_t initialCapacity, UErrorCode &status); virtual ~UVector(); /** * Assign this object to another (make this a copy of 'other'). * Use the 'assign' function to assign each element. */ void assign(const UVector& other, UElementAssigner *assign, UErrorCode &ec); /** * Compare this vector with another. They will be considered * equal if they are of the same size and all elements are equal, * as compared using this object's comparer. */ bool operator==(const UVector& other) const; /** * Equivalent to !operator==() */ inline bool operator!=(const UVector& other) const {return !operator==(other);} //------------------------------------------------------------ // java.util.Vector API //------------------------------------------------------------ /* * Old version of addElement, with non-standard error handling. * Will be removed once all uses have been switched to the new addElement(). */ void addElementX(void* obj, UErrorCode &status); /** * Add an element at the end of the vector. * For use only with vectors that do not adopt their elements, which is to say, * have not set an element deleter function. See `adoptElement()`. */ void addElement(void *obj, UErrorCode &status); /** * Add an element at the end of the vector. * For use only with vectors that adopt their elements, which is to say, * have set an element deleter function. See `addElement()`. * * If the element cannot be successfully added, it will be deleted. This is * normal ICU _adopt_ behavior - one way or another ownership of the incoming * object is transferred from the caller. * * `addElement()` and `adoptElement()` are separate functions to make it easier * to see what the function is doing at call sites. Having a single combined function, * as in earlier versions of UVector, had proved to be error-prone. */ void adoptElement(void *obj, UErrorCode &status); void addElement(int32_t elem, UErrorCode &status); void setElementAt(void* obj, int32_t index); void setElementAt(int32_t elem, int32_t index); void insertElementAt(void* obj, int32_t index, UErrorCode &status); void insertElementAt(int32_t elem, int32_t index, UErrorCode &status); void* elementAt(int32_t index) const; int32_t elementAti(int32_t index) const; UBool equals(const UVector &other) const; inline void* firstElement(void) const {return elementAt(0);} inline void* lastElement(void) const {return elementAt(count-1);} inline int32_t lastElementi(void) const {return elementAti(count-1);} int32_t indexOf(void* obj, int32_t startIndex = 0) const; int32_t indexOf(int32_t obj, int32_t startIndex = 0) const; inline UBool contains(void* obj) const {return indexOf(obj) >= 0;} inline UBool contains(int32_t obj) const {return indexOf(obj) >= 0;} UBool containsAll(const UVector& other) const; UBool removeAll(const UVector& other); UBool retainAll(const UVector& other); void removeElementAt(int32_t index); UBool removeElement(void* obj); void removeAllElements(); inline int32_t size(void) const {return count;} inline UBool isEmpty(void) const {return count == 0;} /* * Old version of ensureCapacity, with non-standard error handling. * Will be removed once all uses have been switched to the new ensureCapacity(). */ UBool ensureCapacityX(int32_t minimumCapacity, UErrorCode &status); UBool ensureCapacity(int32_t minimumCapacity, UErrorCode &status); /** * Change the size of this vector as follows: If newSize is * smaller, then truncate the array, possibly deleting held * elements for i >= newSize. If newSize is larger, grow the * array, filling in new slots with NULL. */ void setSize(int32_t newSize, UErrorCode &status); /** * Fill in the given array with all elements of this vector. */ void** toArray(void** result) const; //------------------------------------------------------------ // New API //------------------------------------------------------------ UObjectDeleter *setDeleter(UObjectDeleter *d); bool hasDeleter() {return deleter != nullptr;} UElementsAreEqual *setComparer(UElementsAreEqual *c); inline void* operator[](int32_t index) const {return elementAt(index);} /** * Removes the element at the given index from this vector and * transfer ownership of it to the caller. After this call, the * caller owns the result and must delete it and the vector entry * at 'index' is removed, shifting all subsequent entries back by * one index and shortening the size of the vector by one. If the * index is out of range or if there is no item at the given index * then 0 is returned and the vector is unchanged. */ void* orphanElementAt(int32_t index); /** * Returns true if this vector contains none of the elements * of the given vector. * @param other vector to be checked for containment * @return true if the test condition is met */ UBool containsNone(const UVector& other) const; /** * Insert the given object into this vector at its sorted position * as defined by 'compare'. The current elements are assumed to * be sorted already. */ void sortedInsert(void* obj, UElementComparator *compare, UErrorCode& ec); /** * Insert the given integer into this vector at its sorted position * as defined by 'compare'. The current elements are assumed to * be sorted already. */ void sortedInsert(int32_t obj, UElementComparator *compare, UErrorCode& ec); /** * Sort the contents of the vector, assuming that the contents of the * vector are of type int32_t. */ void sorti(UErrorCode &ec); /** * Sort the contents of this vector, using a caller-supplied function * to do the comparisons. (It's confusing that * UVector's UElementComparator function is different from the * UComparator function type defined in uarrsort.h) */ void sort(UElementComparator *compare, UErrorCode &ec); /** * Stable sort the contents of this vector using a caller-supplied function * of type UComparator to do the comparison. Provides more flexibility * than UVector::sort() because an additional user parameter can be passed to * the comparison function. */ void sortWithUComparator(UComparator *compare, const void *context, UErrorCode &ec); /** * ICU "poor man's RTTI", returns a UClassID for this class. */ static UClassID U_EXPORT2 getStaticClassID(); /** * ICU "poor man's RTTI", returns a UClassID for the actual class. */ virtual UClassID getDynamicClassID() const override; private: int32_t indexOf(UElement key, int32_t startIndex = 0, int8_t hint = 0) const; void sortedInsert(UElement e, UElementComparator *compare, UErrorCode& ec); public: // Disallow UVector(const UVector&) = delete; // Disallow UVector& operator=(const UVector&) = delete; }; /** * Ultralightweight C++ implementation of a `void*` stack * that is (mostly) compatible with java.util.Stack. As in java, this * is merely a paper thin layer around UVector. See the UVector * documentation for further information. * * *Design notes* * * The element at index `n-1` is (of course) the top of the * stack. * * The poorly named `empty()` method doesn't empty the * stack; it determines if the stack is empty. * * @author Alan Liu */ class U_COMMON_API UStack : public UVector { public: UStack(UErrorCode &status); UStack(int32_t initialCapacity, UErrorCode &status); UStack(UObjectDeleter *d, UElementsAreEqual *c, UErrorCode &status); UStack(UObjectDeleter *d, UElementsAreEqual *c, int32_t initialCapacity, UErrorCode &status); virtual ~UStack(); // It's okay not to have a virtual destructor (in UVector) // because UStack has no special cleanup to do. inline UBool empty(void) const {return isEmpty();} inline void* peek(void) const {return lastElement();} inline int32_t peeki(void) const {return lastElementi();} /** * Pop and return an element from the stack. * For stacks with a deleter function, the caller takes ownership * of the popped element. */ void* pop(void); int32_t popi(void); inline void* push(void* obj, UErrorCode &status) { if (hasDeleter()) { adoptElement(obj, status); return (U_SUCCESS(status)) ? obj : nullptr; } else { addElement(obj, status); return obj; } } inline int32_t push(int32_t i, UErrorCode &status) { addElement(i, status); return i; } /* If the object o occurs as an item in this stack, this method returns the 1-based distance from the top of the stack. */ int32_t search(void* obj) const; /** * ICU "poor man's RTTI", returns a UClassID for this class. */ static UClassID U_EXPORT2 getStaticClassID(); /** * ICU "poor man's RTTI", returns a UClassID for the actual class. */ virtual UClassID getDynamicClassID() const override; // Disallow UStack(const UStack&) = delete; // Disallow UStack& operator=(const UStack&) = delete; }; U_NAMESPACE_END #endif