#include <heappage.h>

Inheritance diagram for HeapPage:

Collaboration diagram for HeapPage:

Public Member Functions
	HeapPage ()=delete
	Constructor. More...

	~HeapPage ()

void	initializeHeader ()
	Initializes header information after the Page is allocated. More...

void	setNext (PageNum page_num)
	Sets next_page to the given PageNum. More...

void	setPrev (PageNum page_num)
	Set prev_page to the given PageNum. More...

PageNum	getNext ()
	Getter for next_page. More...

PageNum	getPrev ()
	Getter for prev_page. More...

std::uint32_t	getFreeSpace ()
	Getter for the amount of free space free on the Page. More...

bool	isFull ()
	bool function indicating whether the Page is full. More...

bool	isEmpty ()
	bool function indicating whether the Page is empty. More...

SlotId	insertRecord (Data *record_data)
	Inserts given record data to the Page. More...

void	getRecord (SlotId slot_id, Data *data)
	Gets the record identified by SlotId. More...

void	deleteRecord (SlotId slot_id)
	Deletes Record identified by SlotId. More...

void	updateRecord (SlotId slot_id, Data *record_data)
	Updates Record identified by SlotId. More...

HeapPageHeader	getHeader ()
	THIS METHOD IS FOR DEBUGGING ONLY. Returns this HeapPage's header information.

SlotInfo	getSlotInfo (SlotId slot_id)
	THIS METHOD IS FOR DEBUGGING ONLY. Returns SlotInfo struct of the given SlotId.

std::uint32_t	getInvalidNum ()
	THIS METHOD IS FOR DEBUGGING ONLY. Returns number of invalid slots in the HeapPage.

void	printHeapPageState ()
	THIS METHOD IS FOR DEBUGGING ONLY. Prints the current state of the HeapPage.

Public Member Functions inherited from Page
	Page ()
	Constructor.

	~Page ()
	Destructor.

char *	getData ()
	Get function for the data char array. More...

Private Member Functions
HeapPageHeader *	_getPageHeader ()
	Getter for the Page header. More...

SlotInfo *	_getSlotDirectory ()
	Return pointer to the where slot directory begins (first SlotInfo) More...

Friends
class	HeapPageScanner

Additional Inherited Members
Protected Attributes inherited from Page
char	data [PAGE_SIZE]
	char array that stores the page data. Derived classes could map appropriate structures on it.

Detailed Description

SwatDB HeapPage Class. HeapPage inherits from base Page class and instantiates heap page, collection of which, form HeapFile.

Constructor & Destructor Documentation

◆ HeapPage()

HeapPage::HeapPage ( )

delete

Constructor.

Constructor should never be called. It should be always the case that base class Page constructor is called by the BufferManager when initializing bufferpool. HeapPage Pointer is casted to whatever Page pointer returned by the BufferManager

◆ ~HeapPage()

HeapPage::~HeapPage ( )

inline

Destructor

Member Function Documentation

◆ _getPageHeader()

HeapPageHeader* HeapPage::_getPageHeader ( )

private

Getter for the Page header.

Returns: Pointer to the HeapPageHeader of the Page (beginning of data array).

◆ _getSlotDirectory()

SlotInfo* HeapPage::_getSlotDirectory ( )

private

Return pointer to the where slot directory begins (first SlotInfo)

Precondition: None

Postcondition: Pointer to first SlotInfo is returned.

Parameters

slot_id SlotId of SlotInfo* that is returned.

Returns: Pointer to the first SlotInfo in slot directory.

◆ deleteRecord()

void HeapPage::deleteRecord ( SlotId slot_id )

Deletes Record identified by SlotId.

Precondition: A valid SlotId is provided as input

Postcondition: The record in that slot is removed from the page, and its slot directory entry is freed. The remaining records on the page are compacted at the end of the page. Page meta data and slot directory entries are updated to reflect the deletion this record. The total amount of freespace on the page increases. The slot directory may shrink by one or more SlotInfo entries as a result of this call.

Parameters

slot_id SlotId of the Record to be deleted.

Exceptions

InvalidSlotIdHeapPage If SlotId is invalid (SlotId is out of range or SlotInfo of the given SlotId has INVALID_SLOT_OFFSET).

◆ getFreeSpace()

std::uint32_t HeapPage::getFreeSpace ( )

Getter for the amount of free space free on the Page.

Precondition: None.

Postcondition: The amount of free space in bytes on the Page is returned. If there is no free slot, sizeof(SlotInfo) is subtracted from the free space returned (accounting extra space occupied if new slot is allocated). If free space is less than sizeof(SlotInfo), 0 is returned.

Returns: Amount of free space in bytes on the Page.

◆ getNext()

PageNum HeapPage::getNext ( )

Getter for next_page.

Precondition: None.

Postcondition: next_page of the page header is returned.

Returns: PageNum of the next Page.

◆ getPrev()

PageNum HeapPage::getPrev ( )

Getter for prev_page.

Precondition: None.

Postcondition: prev_page of the Page header is returned.

Returns: PageNum of the previous Page.

◆ getRecord()

void HeapPage::getRecord	(	SlotId	slot_id,
		Data *	data
	)

Gets the record identified by SlotId.

*

Precondition: A valid SlotId is provided as input and a valid Data with capacity that is greater than maximum size of any Record stored in the Page is passed.

Postcondition: The data field of record_data contains a copy of the requsted record data stored in the Page, and the size the size of Data object is set to the number of bytes of the record.

Parameters

slot_id SlotId of the Record to be retrieved

Exceptions

InvalidSlotIdHeapPage If SlotId is out of range or SlotInfo of the given SlotId has INVALID_SLOT_OFFSET.

◆ initializeHeader()

void HeapPage::initializeHeader ( )

Initializes header information after the Page is allocated.

Precondition: None

Postcondition: Page header is initialized such that prev_page and next_page are set to INVALID_PAGE_NUM, free_space_begin is set to sizeof(HeapPageHeader), free_space_end is set to PAGE_SIZE, size and capacity are set to 0.

◆ insertRecord()

SlotId HeapPage::insertRecord ( Data * record_data )

Inserts given record data to the Page.

If there is enough free space on the Page, and valid record data is passed (the Data value has non-zero length), then the data are inserted into the page.

Precondition: : the slot directory has m used slots in its slot directory and all m records are compacted at the bottom of the page.

Postcondition: : after a successful insert, it has m+1 used slots in its solt directory (possibly increasing the slot directory size by one entry), and all m+1 records are compacted at the bottom of the page.

Parameters

record_data (a pointer to a Data of a record) to be inserted.

Returns: SlotId of the slot the Record is inserted to.

Exceptions

InsufficientSpaceHeapPage	If there is not enough space to insert the record on the page.
EmptyDataHeapPage.	If the passed record data is size 0.

◆ isEmpty()

bool HeapPage::isEmpty ( )

bool function indicating whether the Page is empty.

Precondition: None.

Postcondition: true is returned if size is 0. Else false is returned.

Returns: bool indicating whether the Page is empty.

◆ isFull()

bool HeapPage::isFull ( )

bool function indicating whether the Page is full.

Precondition: None.

Postcondition: true is returned if used space/PAGE_SIZE exceeds MAX_HEAP_PAGE_LOAD and false is returned otherwise.

Returns: bool indicating whether the Page is full.

◆ setNext()

void HeapPage::setNext ( PageNum page_num )

Sets next_page to the given PageNum.

Precondition: None.

Postcondition: next_page is set to the given PageNum.

Parameters

page_num PageNum of the next Page.

◆ setPrev()

void HeapPage::setPrev ( PageNum page_num )

Set prev_page to the given PageNum.

Precondition: None.

Postcondition: prev_page is set to the given PageNum.

Parameters

page_num PageNum of the previous Page.

◆ updateRecord()

void HeapPage::updateRecord	(	SlotId	slot_id,
		Data *	record_data
	)

Updates Record identified by SlotId.

Precondition: A valid SlotId is provided as input and there is enough space in the Page for the updated Record. Valid Data * is provided as input.

Postcondition: The record stored in the slot identified by the given SlotId is updated to the passed record_data value. The record's slotId does not change as a result of a successful update. The orginal record data on the page should not be modified if there is not space on the page to update the record to its new value.

Parameters

slot_id	SlotId of the Record to be updated.
record_data	Data* of the updated Record.

Exceptions

InsufficientSpaceHeapPage	If there is not enough space for updated Record.
InvalidSlotIdHeapPage	If SlotId is invalid (SlotId is out of range or SlotInfo of the given SlotId has INVALID_SLOT_OFFSET).

The documentation for this class was generated from the following file:

heappage.h

Public Member Functions

Private Member Functions

Friends

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ HeapPage()

◆ ~HeapPage()

Member Function Documentation

◆ _getPageHeader()

◆ _getSlotDirectory()

◆ deleteRecord()

◆ getFreeSpace()

◆ getNext()

◆ getPrev()

◆ getRecord()

◆ initializeHeader()

◆ insertRecord()

◆ isEmpty()

◆ isFull()

◆ setNext()

◆ setPrev()

◆ updateRecord()