com.bigdata.btree

Interface ICheckpoint

All Known Implementing Classes:

Checkpoint, IndexSegmentCheckpoint, MetadataIndex.MetadataIndexCheckpoint

public interface ICheckpoint

Metadata for an index checkpoint record.

Author:

Bryan Thompson

Method Summary

Methods

Modifier and Type	Method and Description
long	getBloomFilterAddr() Address of the IBloomFilter.
long	getCheckpointAddr() The address used to read this Checkpoint record from the store.
long	getCounter() Return the value of the B+Tree local counter stored in the Checkpoint record.
long	getEntryCount() The #of index entries (aka tuple count).
int	getGlobalDepth() The global depth of the root directory (HTree only).
int	getHeight() The height of a B+Tree.
IndexTypeEnum	getIndexType() The type of index for this checkpoint record.
long	getLeafCount() The #of leaves (B+Tree), hash buckets (HTree), or ZERO (0) for a solution set stream.
long	getMetadataAddr() Address that can be used to read the IndexMetadata record for the index from the store.
long	getNodeCount() The #of non-leaf nodes (B+Tree) or directories (HTree).
long	getRecordVersion() Return the value of the next record version number to be assigned that is stored in the Checkpoint record.
long	getRootAddr() Address of the root node or leaf of the BTree.
boolean	hasCheckpointAddr() Return true iff the checkpoint address is defined.

Method Detail

getCheckpointAddr

long getCheckpointAddr()

The address used to read this Checkpoint record from the store.

Note: This is set as a side-effect by #write(IRawStore).

Throws:

IllegalStateException - if the Checkpoint record has not been written on a store.

hasCheckpointAddr

boolean hasCheckpointAddr()

Return true iff the checkpoint address is defined.

getMetadataAddr

long getMetadataAddr()

Address that can be used to read the IndexMetadata record for the index from the store.

getRootAddr

long getRootAddr()

Address of the root node or leaf of the BTree.

Returns:

The address of the root -or- 0L iff the index does not have a root page.

getBloomFilterAddr

long getBloomFilterAddr()

Address of the IBloomFilter.

Returns:

The address of the bloom filter -or- 0L iff the index does not have a bloom filter.

getHeight

int getHeight()

The height of a B+Tree. ZERO(0) means just a root leaf. Values greater than zero give the #of levels of abstract nodes. There is always one layer of leaves which is not included in this value.

Returns:

The global depth and ZERO (0) unless the checkpoint record is for an IndexTypeEnum.BTree

getGlobalDepth

int getGlobalDepth()

The global depth of the root directory (HTree only).

Returns:

The global depth and ZERO (0) unless the checkpoint record is for an IndexTypeEnum.HTree

getNodeCount

long getNodeCount()

The #of non-leaf nodes (B+Tree) or directories (HTree). This is ZERO (0) for a non-recursive data structure such as a solution set stream.

getLeafCount

long getLeafCount()

The #of leaves (B+Tree), hash buckets (HTree), or ZERO (0) for a solution set stream.

getEntryCount

long getEntryCount()

The #of index entries (aka tuple count).

getCounter

long getCounter()

Return the value of the B+Tree local counter stored in the Checkpoint record.

getRecordVersion

long getRecordVersion()

Return the value of the next record version number to be assigned that is stored in the Checkpoint record. This number is incremented each time a node or leaf is written onto the backing store. The initial value is ZERO (0). The first value assigned to a node or leaf will be ZERO (0).

getIndexType

IndexTypeEnum getIndexType()

The type of index for this checkpoint record.