com.bigdata.sparse
Class AbstractAtomicRowReadOrWrite

java.lang.Object
  com.bigdata.btree.proc.AbstractIndexProcedure
      com.bigdata.sparse.AbstractAtomicRowReadOrWrite

All Implemented Interfaces:

IIndexProcedure, ISimpleIndexProcedure, IRowStoreConstants, Externalizable, Serializable

Direct Known Subclasses:

AtomicRowDelete, AtomicRowRead, AtomicRowWriteRead

public abstract class AbstractAtomicRowReadOrWrite
extends AbstractIndexProcedure
implements ISimpleIndexProcedure, IRowStoreConstants, Externalizable

Abstract class implements the atomic read operation. However, it does NOT declare itself to be a read-only operation since this class is extended by both AtomicRowRead and AtomicRowWriteRead.

Version:

$Id: AbstractAtomicRowReadOrWrite.java 2265 2009-10-26 12:51:06Z thompsonbry $

Author:

Bryan Thompson

See Also:

Serialized Form

Field Summary

protected static boolean	DEBUG True iff the log level is DEBUG or less.
protected INameFilter	filter
protected long	fromTime
protected static boolean	INFO True iff the log level is INFO or less.
protected static org.apache.log4j.Logger	log
protected Object	primaryKey
protected Schema	schema
protected long	toTime

Fields inherited from interface com.bigdata.sparse.IRowStoreConstants

AUTO_TIMESTAMP, AUTO_TIMESTAMP_UNIQUE, CURRENT_ROW, MAX_TIMESTAMP, MIN_TIMESTAMP

Constructor Summary

protected	AbstractAtomicRowReadOrWrite() De-serialization ctor.
protected	AbstractAtomicRowReadOrWrite(Schema schema, Object primaryKey, long fromTime, long toTime, INameFilter filter) Constructor for an atomic write/read operation.

Method Summary

protected static TPS	atomicRead(IIndex ndx, byte[] fromKey, Schema schema, long fromTime, long toTime, INameFilter filter, TPS tps) Alternative form useful when you have the raw key (unsigned byte[]) rather than a primary key (application object).
protected static TPS	atomicRead(IIndex ndx, Schema schema, Object primaryKey, long fromTime, long toTime, long writeTime, INameFilter filter) Atomic read on the index.
protected static ITPV	getCurrentValue(IIndex ndx, Schema schema, Object primaryKey, String name) Return the current binding for the named property.
void	readExternal(ObjectInput in)
void	writeExternal(ObjectOutput out)

Methods inherited from class com.bigdata.btree.proc.AbstractIndexProcedure

getKeyBuilder

Methods inherited from class java.lang.Object

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

Methods inherited from interface com.bigdata.btree.proc.IIndexProcedure

apply, isReadOnly

Field Detail

log

protected static final org.apache.log4j.Logger log

INFO

protected static final boolean INFO

True iff the log level is INFO or less.

DEBUG

protected static final boolean DEBUG

True iff the log level is DEBUG or less.

schema

protected Schema schema

primaryKey

protected Object primaryKey

fromTime

protected long fromTime

toTime

protected long toTime

filter

protected INameFilter filter

Constructor Detail

AbstractAtomicRowReadOrWrite

protected AbstractAtomicRowReadOrWrite()

De-serialization ctor.

AbstractAtomicRowReadOrWrite

protected AbstractAtomicRowReadOrWrite(Schema schema,
                                       Object primaryKey,
                                       long fromTime,
                                       long toTime,
                                       INameFilter filter)

Constructor for an atomic write/read operation.

Parameters:

schema - The schema governing the property set.

primaryKey - The value of the primary key (identifies the logical row to be read).

fromTime - The first timestamp for which timestamped property values will be accepted.

toTime - The first timestamp for which timestamped property values will NOT be accepted -or- IRowStoreConstants.CURRENT_ROW to accept only the most current binding whose timestamp is GTE fromTime.

filter - An optional filter used to restrict the property values that will be returned.

Method Detail

atomicRead

protected static TPS atomicRead(IIndex ndx,
                                Schema schema,
                                Object primaryKey,
                                long fromTime,
                                long toTime,
                                long writeTime,
                                INameFilter filter)

Atomic read on the index.

Parameters:

ndx - The index on which the data are stored.

schema - The schema governing the row.

primaryKey - The primary key identifies the logical row of interest.

fromTime - The first timestamp for which timestamped property values will be accepted.

toTime - The first timestamp for which timestamped property values will NOT be accepted -or- IRowStoreConstants.CURRENT_ROW to accept only the most current binding whose timestamp is GTE fromTime.

writeTime - The resolved timestamp for an atomic write operation -or- ZERO (0L) IFF the operation is NOT a write.

filter - An optional filter used to select the values for property names accepted by that filter.

Returns:

The logical row for that primary key -or- null iff there is no data for the primaryKey.

atomicRead

protected static TPS atomicRead(IIndex ndx,
                                byte[] fromKey,
                                Schema schema,
                                long fromTime,
                                long toTime,
                                INameFilter filter,
                                TPS tps)

Alternative form useful when you have the raw key (unsigned byte[]) rather than a primary key (application object).

Parameters:

tps -

fromKey -

ndx -

schema -

fromTime -

toTime -

filter -

tps - The object into which the timestamped property values will be read.

Returns:

The TPS -or- null iff there is no data for the logical row which satisified the various criteria (the schema, fromTime, toTime, and filter).

getCurrentValue

protected static ITPV getCurrentValue(IIndex ndx,
                                      Schema schema,
                                      Object primaryKey,
                                      String name)

Return the current binding for the named property.

Parameters:

schema - The schema.

primaryKey - The primary key.

name - The property name.

Returns:

The current binding -or- null iff there is no current binding.

TODO:

this can be optimized by including the encoded column name in the generated [fromKey] and [toKey] so that we scan less data from the index and by using a reverse traversal iterator to read the most recent value in the key range first. This is especially important if timeseries data are being stored.

readExternal

public void readExternal(ObjectInput in)
                  throws IOException,
                         ClassNotFoundException

Specified by:

readExternal in interface Externalizable

Throws:

IOException

ClassNotFoundException

writeExternal

public void writeExternal(ObjectOutput out)
                   throws IOException

Specified by:

writeExternal in interface Externalizable

Throws:

IOException