org.yamcs.yarch

Class PartitionManager

java.lang.Object

org.yamcs.yarch.PartitionManager

Direct Known Subclasses:

RdbPartitionManager

public abstract class PartitionManager
extends Object

Keeps track of partitions. This class is used and by the engines (TokyoCabinets, RocksDB) where the partitioning is kept track inside yamcs. If the StorageEngine has built-in partitioning (e.g. mysql), there is no need for this.

Author:

nm

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	PartitionManager.Interval Keeps a value -> partition map for a specific time interval

Field Summary

Fields

Modifier and Type	Field and Description
protected NavigableMap<Long,PartitionManager.Interval>	intervals
protected PartitioningSpec	partitioningSpec
protected PartitionManager.Interval	pcache
protected TableDefinition	tableDefinition

Constructor Summary

Constructors

Constructor and Description
PartitionManager(TableDefinition tableDefinition)

Method Summary

Modifier and Type	Method and Description
Partition	createAndGetPartition(long instant, Object value) Creates (if not already existing) and returns the partition in which the instant,value should be written.
protected abstract Partition	createPartition(Object value) Create a partition for value based partitioning
protected abstract Partition	createPartitionByTime(TimePartitionSchema.PartitionInfo pinfo, Object value) Create a partition for time (and possible value) based partitioning
Partition	getPartitionForTuple(Tuple t) Gets partition where tuple has to be written.
List<Partition>	getPartitions() Retrieves the existing partitions
Iterator<List<Partition>>	iterator(long start, Set<Object> partitionValueFilter) See iterator(Set)
Iterator<List<Partition>>	iterator(Set<Object> partitionValueFilter) Returns an iterator which at each step gives the list of partition corresponding to a time interval (so when we do a replay those partitions have to be played in parallel).
Iterator<List<Partition>>	reverseIterator(long start, Set<Object> partitionValueFilter)
Iterator<List<Partition>>	reverseIterator(Set<Object> partitionValueFilter) same as above, only in reverse direction

Methods inherited from class java.lang.Object

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

Field Detail

tableDefinition

protected final TableDefinition tableDefinition

partitioningSpec

protected final PartitioningSpec partitioningSpec

intervals

protected NavigableMap<Long,PartitionManager.Interval> intervals

pcache

protected PartitionManager.Interval pcache

Constructor Detail

PartitionManager

public PartitionManager(TableDefinition tableDefinition)

Method Detail

iterator

public Iterator<List<Partition>> iterator(Set<Object> partitionValueFilter)

Returns an iterator which at each step gives the list of partition corresponding to a time interval (so when we do a replay those partitions have to be played in parallel). The iterator returns intervals sorted on time.

Parameters:

partitionValueFilter - - return only partitions whose value are in the filter. If null, return all partitions;

Returns:

iterator going over partitions

reverseIterator

public Iterator<List<Partition>> reverseIterator(Set<Object> partitionValueFilter)

same as above, only in reverse direction

Parameters:

partitionValueFilter -

Returns:

iterator

public Iterator<List<Partition>> iterator(long start,
                                          Set<Object> partitionValueFilter)

See iterator(Set)

Parameters:

start -

partitionValueFilter - values - return only partitions whose value are in the filter. If null, return all partitions;

Returns:

an iterator over the partitions starting at the specified start time

reverseIterator

public Iterator<List<Partition>> reverseIterator(long start,
                                                 Set<Object> partitionValueFilter)

createAndGetPartition

public Partition createAndGetPartition(long instant,
                                       Object value)
                                throws IOException

Creates (if not already existing) and returns the partition in which the instant,value should be written. value can be null (in case of no value partitioning)

Parameters:

instant - - time for which the partition has to be created - can be TimeEncoding.INVALID in case value only or no partitioning

value - - value for which the partition has to be created - can be null in case of time only or no partitioning. For the enum partitions, the value is the index (type Short) rather than the string.

Returns:

a Partition

Throws:

IOException

getPartitionForTuple

public Partition getPartitionForTuple(Tuple t)
                               throws IOException

Gets partition where tuple has to be written. Creates the partition if necessary.

Parameters:

t -

Returns:

the partition where the tuple has to be written

Throws:

IOException

createPartitionByTime

protected abstract Partition createPartitionByTime(TimePartitionSchema.PartitionInfo pinfo,
                                                   Object value)
                                            throws IOException

Create a partition for time (and possible value) based partitioning

Parameters:

pinfo -

value -

Returns:

Throws:

IOException

createPartition

protected abstract Partition createPartition(Object value)
                                      throws IOException

Create a partition for value based partitioning

Parameters:

value -

Returns:

Throws:

IOException

getPartitions

public List<Partition> getPartitions()

Retrieves the existing partitions

Returns:

list of all existing partitions