org.apache.hadoop.hbase.constraint

Class ConstraintProcessor

java.lang.Object

org.apache.hadoop.hbase.constraint.ConstraintProcessor

All Implemented Interfaces:

Coprocessor, RegionObserver

@InterfaceAudience.Private
public class ConstraintProcessor
extends Object
implements RegionObserver

Processes multiple Constraints on a given table.

This is an ease of use mechanism - all the functionality here could be implemented on any given system by a coprocessor.

Nested Class Summary

Nested classes/interfaces inherited from interface org.apache.hadoop.hbase.coprocessor.RegionObserver

RegionObserver.MutationType

Nested classes/interfaces inherited from interface org.apache.hadoop.hbase.Coprocessor

Coprocessor.State

Field Summary

Fields inherited from interface org.apache.hadoop.hbase.Coprocessor

PRIORITY_HIGHEST, PRIORITY_LOWEST, PRIORITY_SYSTEM, PRIORITY_USER, VERSION

Constructor Summary

Constructors

Constructor and Description
ConstraintProcessor() Create the constraint processor.

Method Summary

Modifier and Type	Method and Description
boolean	postScannerFilterRow(ObserverContext<RegionCoprocessorEnvironment> e, InternalScanner s, Cell curRowCell, boolean hasMore) This will be called by the scan flow when the current scanned row is being filtered out by the filter.
void	prePut(ObserverContext<RegionCoprocessorEnvironment> e, Put put, WALEdit edit, Durability durability) Called before the client stores a value.
void	start(CoprocessorEnvironment environment)

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.apache.hadoop.hbase.coprocessor.RegionObserver

postAppend, postBatchMutate, postBatchMutateIndispensably, postBulkLoadHFile, postCheckAndDelete, postCheckAndPut, postClose, postCloseRegionOperation, postCommitStoreFile, postCompact, postCompactSelection, postDelete, postExists, postFlush, postFlush, postGetOp, postIncrement, postInstantiateDeleteTracker, postLogReplay, postMutationBeforeWAL, postOpen, postPut, postReplayWALs, postScannerClose, postScannerNext, postScannerOpen, postStartRegionOperation, postStoreFileReaderOpen, postWALRestore, preAppend, preAppendAfterRowLock, preBatchMutate, preBulkLoadHFile, preCheckAndDelete, preCheckAndDeleteAfterRowLock, preCheckAndPut, preCheckAndPutAfterRowLock, preClose, preCommitStoreFile, preCompact, preCompactScannerOpen, preCompactSelection, preDelete, preExists, preFlush, preFlush, preFlushScannerOpen, preGetOp, preIncrement, preIncrementAfterRowLock, preOpen, prePrepareTimeStampForDeleteVersion, preReplayWALs, preScannerClose, preScannerNext, preScannerOpen, preStoreFileReaderOpen, preStoreScannerOpen, preWALRestore

Methods inherited from interface org.apache.hadoop.hbase.Coprocessor

stop

Constructor Detail

ConstraintProcessor

public ConstraintProcessor()

Create the constraint processor.

Stores the current classloader.

Method Detail

start

public void start(CoprocessorEnvironment environment)

Specified by:

start in interface Coprocessor

prePut

public void prePut(ObserverContext<RegionCoprocessorEnvironment> e,
                   Put put,
                   WALEdit edit,
                   Durability durability)
            throws IOException

Description copied from interface: RegionObserver

Called before the client stores a value.

Call CoprocessorEnvironment#bypass to skip default actions

Call CoprocessorEnvironment#complete to skip any subsequent chained coprocessors

Note: Do not retain references to any Cells in 'put' beyond the life of this invocation. If need a Cell reference for later use, copy the cell and use that.

Specified by:

prePut in interface RegionObserver

Parameters:

e - the environment provided by the region server

put - The Put object

edit - The WALEdit object that will be written to the wal

durability - Persistence guarantee for this Put

Throws:

IOException

postScannerFilterRow

public boolean postScannerFilterRow(ObserverContext<RegionCoprocessorEnvironment> e,
                                    InternalScanner s,
                                    Cell curRowCell,
                                    boolean hasMore)
                             throws IOException

Description copied from interface: RegionObserver

This will be called by the scan flow when the current scanned row is being filtered out by the filter. The filter may be filtering out the row via any of the below scenarios

1. boolean filterRowKey(byte [] buffer, int offset, int length) returning true
2. boolean filterRow() returning true
3. default void filterRow(List<KeyValue> kvs) removing all the kvs from the passed List

Note: Do not retain references to any Cells returned by scanner, beyond the life of this invocation. If need a Cell reference for later use, copy the cell and use that.

Specified by:

postScannerFilterRow in interface RegionObserver

Parameters:

e - the environment provided by the region server

s - the scanner

curRowCell - The cell in the current row which got filtered out

hasMore - the 'has more' indication

Returns:

whether more rows are available for the scanner or not

Throws:

IOException