virtualx-engine/thirdparty/icu4c/common/uvector.h
2021-10-28 09:15:28 +03:00

398 lines
13 KiB
C++

// © 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