Class cBlockRecordArray

src/db/blockrecordarray.h:54–235

class eArchive;

class cBlockRecordArray
{
public:
    //-------------------------------------------------------------------------------------
    // Construction
    //-------------------------------------------------------------------------------------
    cBlockRecordArray(cBlockFile* pBlockFile, int blockNum);
    // this object is associated with a single block in a cBlockFile. It is _not_
    // asserted that the blockNum is valid for the associated file at this point,
    // since it is possible that the file has not been loaded yet
    cBlockRecordArray();
    // if this version of the ctor is called, then Init() must be called before it can be used.
    void Init(cBlockFile* pBlockFile, int blockNum);

    virtual ~cBlockRecordArray();

    //-------------------------------------------------------------------------------------
    // Initialization ... exactly one of these methods must be called before this class can be used
    //-------------------------------------------------------------------------------------
    void InitNewBlock(); //throw (eArchive)
        // this method should be called when a new block has been created, and before this
        // class operates on it.
    void InitForExistingBlock(); //throw (eArchive)
        // this method should be called to initialize this class for use with a block that has
        // previously been created and initialized with InitNewBlock().

    //-------------------------------------------------------------------------------------
    // Data Manipulation
    //-------------------------------------------------------------------------------------
    int AddItem(int8* pData, int dataSize, int mainIndex); //throw (eArchive)
        // inserts the given item into the array; returns the index that it was inserted into.
        // this asserts that there is room for the new element, and updates the avail. space and
        // max index as necessary.
    void DeleteItem(int index); //throw (eArchive)
        // deletes the specified item; this asserts that the index is valid, and updates the avail.
        // space and max index as necessary.
    int8* GetDataForReading(int index, int32& dataSize); //throw (eArchive)
        // returns a pointer to the named data. This method will assert that the address is
        // valid. The data pointer returned is guarenteed to be valid only until the next
        // method call into this class.
    int8* GetDataForWriting(int index, int32& dataSize); //throw (eArchive)
        // this is the same as the previous function, except the dirty bit for the page is also set
    bool IsItemValid(int index) const; //throw (eArchive)
        // returns true if the given index has a valid value.

    bool IsClassValid() const;
    // returns true if the class has an internally consistant state. If an archive exception
    // occurs, false is returned. This method is good for determining if a newly opened block
    // file is actually a block file

    bool Initialized() const
    {
        return mbInit;
    }
    int GetAvailableSpace() const
    {
        ASSERT(Initialized());
        return mSpaceAvailable;