com.bigdata.rawstore

Interface IAddressManager

All Known Subinterfaces:

IAtomicStore, IBufferStrategy, IDiskBasedStrategy, IHABufferStrategy, IHAJournal, IJournal, IRawStore, IRWStrategy

All Known Implementing Classes:

AbstractBufferStrategy, AbstractJournal, AbstractRawStore, AbstractRawWormStore, BasicBufferStrategy, DirectBufferStrategy, DiskBackedBufferStrategy, DiskOnlyStrategy, IndexSegmentAddressManager, IndexSegmentStore, Journal, JournalDelegate, MappedBufferStrategy, MemStore, MemStrategy, RawStoreDelegate, RWAddressManager, RWStrategy, SimpleFileRawStore, SimpleMemoryRawStore, StoreManager.ManagedJournal, TemporaryRawStore, TemporaryStore, TransientBufferStrategy, WormAddressManager, WORMStrategy

public interface IAddressManager

An interface that encapsulates operations on opaque identifiers used to locate data within an IRawStore.

Version:

$Id$

Author:

Bryan Thompson

Field Summary

Fields

Modifier and Type	Field and Description
static long	NULL A null reference (0L).

Method Summary

Methods

Modifier and Type	Method and Description
int	getByteCount(long addr) The length of the datum in bytes.
long	getOffset(long addr) The offset on the store at which the datum is stored.
long	getPhysicalAddress(long addr) Determine the unencoded physical address
long	toAddr(int nbytes, long offset) Converts a byte count and offset into a long integer.
String	toString(long addr) A human readable representation of the address.

Field Detail

NULL

static final long NULL

A null reference (0L).

Note: It is a requirement that all implementations understand the value 0L as a null reference.

See Also:

Constant Field Values

Method Detail

toAddr

long toAddr(int nbytes,
          long offset)

Converts a byte count and offset into a long integer.

Parameters:

nbytes - The byte count.

offset - The byte offset.

Returns:

The long integer.

Throws:

IllegalArgumentException - if the byte count is larger than can be represented by the address manager.

IllegalArgumentException - if the byte offset is larger than can be represented by the address manager.

getOffset

long getOffset(long addr)

The offset on the store at which the datum is stored. While this is often the offset of a byte into a file on disk, implementations MAY assign offsets using other strategies.

Parameters:

addr - The opaque identifier that is the within store locator for some datum.

Returns:

The offset of that datum.

getByteCount

int getByteCount(long addr)

The length of the datum in bytes. This must be the actual length of the record on the disk, not the length of the caller's byte[]. This is necessary in order to support transparent checksums and/or compression for records in the IRawStore.

Parameters:

addr - The opaque identifier that is the within store locator for some datum.

Returns:

The offset of that datum.

toString

String toString(long addr)

A human readable representation of the address.

Parameters:

addr - The opaque identifier that is the within store locator for some datum.

Returns:

A human readable representation.

getPhysicalAddress

long getPhysicalAddress(long addr)

Determine the unencoded physical address

Parameters:

addr - The encoded address

Returns:

an unencoded address offset