RegionMergeCoordination (Apache HBase 1.4.11 API)

All Known Implementing Classes:

ZkRegionMergeCoordination
```
@InterfaceAudience.Private
public interface RegionMergeCoordination
```
Coordination operations for region merge transaction. The operation should be coordinated at the following stages:
1. startRegionMergeTransaction - all preparation/initialization for merge region transaction
2. waitForRegionMergeTransaction - wait until coordination complete all works related to merge
3. confirmRegionMergeTransaction - confirm that the merge could be completed and none of merging regions moved somehow
4. completeRegionMergeTransaction - all steps that are required to complete the transaction. Called after PONR (point of no return)

Nested Class Summary

Nested Classes
Modifier and Type Interface and Description

static interface RegionMergeCoordination.RegionMergeDetails
Dummy interface for region merge transaction details.

Nested Classes
Modifier and Type	Interface and Description
`static interface`	`RegionMergeCoordination.RegionMergeDetails` Dummy interface for region merge transaction details.

Method Summary

Methods
Modifier and Type	Method and Description
`void`	`clean(HRegionInfo merged)` This method is used during rollback
`void`	`completeRegionMergeTransaction(RegionServerServices services, HRegionInfo merged, HRegion region_a, HRegion region_b, RegionMergeCoordination.RegionMergeDetails rmd, HRegion mergedRegion)` Finish off merge transaction
`void`	`confirmRegionMergeTransaction(HRegionInfo merged, HRegionInfo a, HRegionInfo b, ServerName serverName, RegionMergeCoordination.RegionMergeDetails rmd)` Confirm that the region merge can be performed
`RegionMergeCoordination.RegionMergeDetails`	`getDefaultDetails()`
`void`	`processRegionMergeRequest(HRegionInfo merged, HRegionInfo a, HRegionInfo b, ServerName serverName, RegionMergeCoordination.RegionMergeDetails rmd)`
`void`	`startRegionMergeTransaction(HRegionInfo region, ServerName serverName, HRegionInfo a, HRegionInfo b)` Start the region merge transaction
`void`	`waitForRegionMergeTransaction(RegionServerServices services, HRegionInfo mergedRegionInfo, HRegion region_a, HRegion region_b, RegionMergeCoordination.RegionMergeDetails details)` Get everything ready for region merge

Method Detail

getDefaultDetails

RegionMergeCoordination.RegionMergeDetails getDefaultDetails()

startRegionMergeTransaction

void startRegionMergeTransaction(HRegionInfo region,
                               ServerName serverName,
                               HRegionInfo a,
                               HRegionInfo b)
                                 throws IOException

Start the region merge transaction

Parameters:: region - region to be created as offline; serverName - server event originates from
Throws:: IOException

waitForRegionMergeTransaction

void waitForRegionMergeTransaction(RegionServerServices services,
                                 HRegionInfo mergedRegionInfo,
                                 HRegion region_a,
                                 HRegion region_b,
                                 RegionMergeCoordination.RegionMergeDetails details)
                                   throws IOException

Get everything ready for region merge

Throws:: IOException

confirmRegionMergeTransaction

void confirmRegionMergeTransaction(HRegionInfo merged,
                                 HRegionInfo a,
                                 HRegionInfo b,
                                 ServerName serverName,
                                 RegionMergeCoordination.RegionMergeDetails rmd)
                                   throws IOException

Confirm that the region merge can be performed

Parameters:: merged - region; a - merging region A; b - merging region B; serverName - server event originates from; rmd - region merge details
Throws:: IOException - If thrown, transaction failed.

processRegionMergeRequest

void processRegionMergeRequest(HRegionInfo merged,
                             HRegionInfo a,
                             HRegionInfo b,
                             ServerName serverName,
                             RegionMergeCoordination.RegionMergeDetails rmd)
                               throws IOException

Parameters:: merged - region; a - merging region A; b - merging region B; serverName - server event originates from; rmd - region merge details
Throws:: IOException

completeRegionMergeTransaction

void completeRegionMergeTransaction(RegionServerServices services,
                                  HRegionInfo merged,
                                  HRegion region_a,
                                  HRegion region_b,
                                  RegionMergeCoordination.RegionMergeDetails rmd,
                                  HRegion mergedRegion)
                                    throws IOException

Finish off merge transaction

Parameters:: services - Used to online/offline regions.; merged - region; region_a - merging region A; region_b - merging region B; rmd - region merge details; mergedRegion -
Throws:: IOException - If thrown, transaction failed. Call RegionMergeTransaction.rollback( Server, RegionServerServices)

clean
```
void clean(HRegionInfo merged)
```
This method is used during rollback

Parameters:
merged - region to be rolled back

Interface RegionMergeCoordination

Nested Class Summary

Method Summary

Method Detail

getDefaultDetails

startRegionMergeTransaction

waitForRegionMergeTransaction

confirmRegionMergeTransaction

processRegionMergeRequest

completeRegionMergeTransaction

clean