org.apache.xindice.core.meta.inline
Class InlineMetaService

java.lang.Object
  org.apache.xindice.core.meta.inline.InlineMetaService

public class InlineMetaService

extends Object

If the documents in a collection have headers, the Collection object holds an instance of this class. All services the collection needs for working with inline metadata are provided by this class.

Version:

$Revision: 571950 $, $Date: 2007-09-02 06:53:17 -0400 (Sun, 02 Sep 2007) $

Nested Class Summary

static class

InlineMetaService.DatabaseEntry Utility class for returning an InlineMetaMap and Value from readDatabaseEntry(Value).

Field Summary

static Class	currentMapClass The InlineMetaMap class associated with the current header version.
static InlineMetaWriter	currentWriter The writer corresponding to the current header version.
static InlineMetaReader[]	readerByVersion The known readers.

Constructor Summary

InlineMetaService()

Method Summary

Value	createValue(InlineMetaMap map, byte[] data, int offset, int length) Create a Value object containing the appropriate header and data.
InlineMetaMap	getEmptyMap() Get an InlineMetaMap instance corresponding to the current header version.
boolean	haveReaderForVersion(int version) Returns true if a reader is available for the specified version.
InlineMetaService.DatabaseEntry	readDatabaseEntry(Value rawValue) Given a Value object from the database, disassemble it into its component metadata and entry data components.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

readerByVersion

public static final InlineMetaReader[] readerByVersion

The known readers. All readers for header versions up to and including the current version must be present in this array.

currentWriter

public static final InlineMetaWriter currentWriter

The writer corresponding to the current header version.

currentMapClass

public static final Class currentMapClass

The InlineMetaMap class associated with the current header version. When the Collection fills in an InlineMetaMap object prior to a store, it is working with this class.

Constructor Detail

InlineMetaService

public InlineMetaService()

Method Detail

getEmptyMap

public InlineMetaMap getEmptyMap()

Get an InlineMetaMap instance corresponding to the current header version. Used by Collection to inform the InlineMeta code of the metadata values for the entry being stored.

Returns:

InlineMetaMap instance

createValue

public Value createValue(InlineMetaMap map,
                         byte[] data,
                         int offset,
                         int length)
                  throws InlineMetaException

Create a Value object containing the appropriate header and data. This utility method takes the metadata and the data for the entry to be stored in the database and creates a Value object containing both, ready to store.

Parameters:

map - containing metadata

data - containing entry to be stored in database

offset - in the data to the beginning of the entry

length - of the entry

Returns:

Value object containing the header + entry, ready to store

Throws:

InlineMetaException - if the metadata is incomplete

haveReaderForVersion

public boolean haveReaderForVersion(int version)

Returns true if a reader is available for the specified version.

Parameters:

version - of the header

Returns:

true if a reader is available for the given version

readDatabaseEntry

public InlineMetaService.DatabaseEntry readDatabaseEntry(Value rawValue)
                                                  throws InlineMetaException

Given a Value object from the database, disassemble it into its component metadata and entry data components.

Parameters:

rawValue - containing raw header + entry data from the backing store

Returns:

DatabaseEntry containing metadata in an InlineMetaMap and entry data in a Value.

Throws:

InlineMetaException - if missing the reader for the header, or if the header is corrupted.