LockProcedure (Apache HBase - Server 2.1.3 API)

java.lang.Object
- org.apache.hadoop.hbase.procedure2.Procedure<MasterProcedureEnv>
- - org.apache.hadoop.hbase.master.locking.LockProcedure

All Implemented Interfaces:

Comparable<org.apache.hadoop.hbase.procedure2.Procedure<MasterProcedureEnv>>, TableProcedureInterface
```
@InterfaceAudience.Private
public final class LockProcedure
extends org.apache.hadoop.hbase.procedure2.Procedure<MasterProcedureEnv>
implements TableProcedureInterface
```
Procedure to allow blessed clients and external admin tools to take our internal Schema locks used by the procedure framework isolating procedures doing creates/deletes etc. on table/namespace/regions. This procedure when scheduled, acquires specified locks, suspends itself and waits for:
- Call to unlock: if lock request came from the process itself, say master chore.
- Timeout : if lock request came from RPC. On timeout, evaluates if it should continue holding the lock or not based on last heartbeat timestamp.

Nested Class Summary
- Nested classes/interfaces inherited from class org.apache.hadoop.hbase.procedure2.Procedure
  org.apache.hadoop.hbase.procedure2.Procedure.LockState
- Nested classes/interfaces inherited from interface org.apache.hadoop.hbase.master.procedure.TableProcedureInterface
  TableProcedureInterface.TableOperationType

Field Summary

Fields
Modifier and Type	Field and Description
`static int`	`DEFAULT_LOCAL_MASTER_LOCKS_TIMEOUT_MS`
`static int`	`DEFAULT_REMOTE_LOCKS_TIMEOUT_MS`
`static String`	`LOCAL_MASTER_LOCKS_TIMEOUT_MS_CONF`
`static String`	`REMOTE_LOCKS_TIMEOUT_MS_CONF`

Fields inherited from class org.apache.hadoop.hbase.procedure2.Procedure
NO_PROC_ID, NO_TIMEOUT

Constructor Summary

Constructors
Constructor and Description
`LockProcedure()`
`LockProcedure(org.apache.hadoop.conf.Configuration conf, org.apache.hadoop.hbase.client.RegionInfo[] regionInfos, org.apache.hadoop.hbase.procedure2.LockType type, String description, CountDownLatch lockAcquireLatch)` Constructor for region lock(s).
`LockProcedure(org.apache.hadoop.conf.Configuration conf, String namespace, org.apache.hadoop.hbase.procedure2.LockType type, String description, CountDownLatch lockAcquireLatch)` Constructor for namespace lock.
`LockProcedure(org.apache.hadoop.conf.Configuration conf, org.apache.hadoop.hbase.TableName tableName, org.apache.hadoop.hbase.procedure2.LockType type, String description, CountDownLatch lockAcquireLatch)` Constructor for table lock.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`protected boolean`	`abort(MasterProcedureEnv env)`
`protected org.apache.hadoop.hbase.procedure2.Procedure.LockState`	`acquireLock(MasterProcedureEnv env)`
`protected void`	`beforeReplay(MasterProcedureEnv env)` On recovery, re-execute from start to acquire the locks.
`protected void`	`deserializeStateData(org.apache.hadoop.hbase.procedure2.ProcedureStateSerializer serializer)`
`protected org.apache.hadoop.hbase.procedure2.Procedure<MasterProcedureEnv>[]`	`execute(MasterProcedureEnv env)`
`String`	`getDescription()`
`org.apache.hadoop.hbase.TableName`	`getTableName()`
`TableProcedureInterface.TableOperationType`	`getTableOperationType()` Given an operation type we can take decisions about what to do with pending operations.
`org.apache.hadoop.hbase.procedure2.LockType`	`getType()`
`boolean`	`holdLock(MasterProcedureEnv env)`
`boolean`	`isLocked()`
`protected void`	`releaseLock(MasterProcedureEnv env)`
`protected void`	`rollback(MasterProcedureEnv env)`
`protected void`	`serializeStateData(org.apache.hadoop.hbase.procedure2.ProcedureStateSerializer serializer)`
`protected boolean`	`setTimeoutFailure(MasterProcedureEnv env)` Re run the procedure after every timeout to write new WAL entries so we don't hold back old WALs.
`protected void`	`toStringClassDetails(StringBuilder builder)`
`void`	`unlock(MasterProcedureEnv env)`
`void`	`updateHeartBeat()` Updates timeout deadline for the lock.

Methods inherited from class org.apache.hadoop.hbase.procedure2.Procedure
addStackIndex, afterReplay, bypass, compareTo, completionCleanup, doExecute, doRollback, elapsedTime, getChildrenLatch, getException, getLastUpdate, getNonceKey, getOwner, getParentProcId, getProcedureMetrics, getProcId, getProcIdHashCode, getProcName, getResult, getRootProcedureId, getRootProcId, getStackIndexes, getState, getSubmittedTime, getTimeout, getTimeoutTimestamp, hasChildren, hasException, hasLock, hasOwner, hasParent, hasTimeout, haveSameParent, incChildrenLatch, isBypass, isFailed, isFinished, isInitializing, isLockedWhenLoading, isRunnable, isSuccess, isWaiting, isYieldAfterExecutionStep, removeStackIndex, setAbortFailure, setChildrenLatch, setFailure, setFailure, setLastUpdate, setNonceKey, setOwner, setOwner, setParentProcId, setProcId, setResult, setRootProcId, setStackIndexes, setState, setSubmittedTime, setTimeout, shouldWaitClientAck, skipPersistence, toString, toStringClass, toStringDetails, toStringSimpleSB, toStringState, updateMetricsOnFinish, updateMetricsOnSubmit, updateTimestamp, waitInitialized, wasExecuted

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

- Field Detail
  - DEFAULT_REMOTE_LOCKS_TIMEOUT_MS
```
public static final int DEFAULT_REMOTE_LOCKS_TIMEOUT_MS
```
    See Also:
    
    Constant Field Values
  - REMOTE_LOCKS_TIMEOUT_MS_CONF
```
public static final String REMOTE_LOCKS_TIMEOUT_MS_CONF
```
    See Also:
    
    Constant Field Values
  - DEFAULT_LOCAL_MASTER_LOCKS_TIMEOUT_MS
```
public static final int DEFAULT_LOCAL_MASTER_LOCKS_TIMEOUT_MS
```
    See Also:
    
    Constant Field Values
  - LOCAL_MASTER_LOCKS_TIMEOUT_MS_CONF
```
public static final String LOCAL_MASTER_LOCKS_TIMEOUT_MS_CONF
```
    See Also:
    
    Constant Field Values
- Constructor Detail
  - LockProcedure
```
public LockProcedure()
```
  - LockProcedure
```
public LockProcedure(org.apache.hadoop.conf.Configuration conf,
                     String namespace,
                     org.apache.hadoop.hbase.procedure2.LockType type,
                     String description,
                     CountDownLatch lockAcquireLatch)
              throws IllegalArgumentException
```
    Constructor for namespace lock.
    
    Parameters:
    
    lockAcquireLatch - if not null, the latch is decreased when lock is acquired.
    
    Throws:
    
    IllegalArgumentException
  - LockProcedure
```
public LockProcedure(org.apache.hadoop.conf.Configuration conf,
                     org.apache.hadoop.hbase.TableName tableName,
                     org.apache.hadoop.hbase.procedure2.LockType type,
                     String description,
                     CountDownLatch lockAcquireLatch)
              throws IllegalArgumentException
```
    Constructor for table lock.
    
    Parameters:
    
    lockAcquireLatch - if not null, the latch is decreased when lock is acquired.
    
    Throws:
    
    IllegalArgumentException
  - LockProcedure
```
public LockProcedure(org.apache.hadoop.conf.Configuration conf,
                     org.apache.hadoop.hbase.client.RegionInfo[] regionInfos,
                     org.apache.hadoop.hbase.procedure2.LockType type,
                     String description,
                     CountDownLatch lockAcquireLatch)
              throws IllegalArgumentException
```
    Constructor for region lock(s).
    
    Parameters:
    
    lockAcquireLatch - if not null, the latch is decreased when lock is acquired. Useful for locks acquired locally from master process.
    
    Throws:
    
    IllegalArgumentException - if all regions are not from same table.
- Method Detail
  - getTableName
```
public org.apache.hadoop.hbase.TableName getTableName()
```
    Specified by:
    
    getTableName in interface TableProcedureInterface
    
    Returns:
    
    the name of the table the procedure is operating on
  - getTableOperationType
```
public TableProcedureInterface.TableOperationType getTableOperationType()
```
    Description copied from interface: TableProcedureInterface
    
    Given an operation type we can take decisions about what to do with pending operations. e.g. if we get a delete and we have some table operation pending (e.g. add column) we can abort those operations.
    
    Specified by:
    
    getTableOperationType in interface TableProcedureInterface
    
    Returns:
    
    the operation type that the procedure is executing.
  - updateHeartBeat
```
public void updateHeartBeat()
```
    Updates timeout deadline for the lock.
  - setTimeoutFailure
```
protected boolean setTimeoutFailure(MasterProcedureEnv env)
```
    Re run the procedure after every timeout to write new WAL entries so we don't hold back old WALs.
    
    Overrides:
    
    setTimeoutFailure in class org.apache.hadoop.hbase.procedure2.Procedure<MasterProcedureEnv>
    
    Returns:
    
    false, so procedure framework doesn't mark this procedure as failure.
  - unlock
```
public void unlock(MasterProcedureEnv env)
```
  - execute
```
protected org.apache.hadoop.hbase.procedure2.Procedure<MasterProcedureEnv>[] execute(MasterProcedureEnv env)
                                                                              throws org.apache.hadoop.hbase.procedure2.ProcedureSuspendedException
```
    Specified by:
    
    execute in class org.apache.hadoop.hbase.procedure2.Procedure<MasterProcedureEnv>
    
    Throws:
    
    org.apache.hadoop.hbase.procedure2.ProcedureSuspendedException
  - rollback
```
protected void rollback(MasterProcedureEnv env)
```
    Specified by:
    
    rollback in class org.apache.hadoop.hbase.procedure2.Procedure<MasterProcedureEnv>
  - abort
```
protected boolean abort(MasterProcedureEnv env)
```
    Specified by:
    
    abort in class org.apache.hadoop.hbase.procedure2.Procedure<MasterProcedureEnv>
  - serializeStateData
```
protected void serializeStateData(org.apache.hadoop.hbase.procedure2.ProcedureStateSerializer serializer)
                           throws IOException
```
    Specified by:
    
    serializeStateData in class org.apache.hadoop.hbase.procedure2.Procedure<MasterProcedureEnv>
    
    Throws:
    
    IOException
  - deserializeStateData
```
protected void deserializeStateData(org.apache.hadoop.hbase.procedure2.ProcedureStateSerializer serializer)
                             throws IOException
```
    Specified by:
    
    deserializeStateData in class org.apache.hadoop.hbase.procedure2.Procedure<MasterProcedureEnv>
    
    Throws:
    
    IOException
  - acquireLock
```
protected org.apache.hadoop.hbase.procedure2.Procedure.LockState acquireLock(MasterProcedureEnv env)
```
    Overrides:
    
    acquireLock in class org.apache.hadoop.hbase.procedure2.Procedure<MasterProcedureEnv>
  - releaseLock
```
protected void releaseLock(MasterProcedureEnv env)
```
    Overrides:
    
    releaseLock in class org.apache.hadoop.hbase.procedure2.Procedure<MasterProcedureEnv>
  - beforeReplay
```
protected void beforeReplay(MasterProcedureEnv env)
```
    On recovery, re-execute from start to acquire the locks. Need to explicitly set it to RUNNABLE because the procedure might have been in WAITING_TIMEOUT state when crash happened. In which case, it'll be sent back to timeout queue on recovery, which we don't want since we want to require locks.
    
    Overrides:
    
    beforeReplay in class org.apache.hadoop.hbase.procedure2.Procedure<MasterProcedureEnv>
  - toStringClassDetails
```
protected void toStringClassDetails(StringBuilder builder)
```
    Overrides:
    
    toStringClassDetails in class org.apache.hadoop.hbase.procedure2.Procedure<MasterProcedureEnv>
  - getType
```
public org.apache.hadoop.hbase.procedure2.LockType getType()
```
  - getDescription
```
public String getDescription()
```
  - isLocked
```
public boolean isLocked()
```
  - holdLock
```
public boolean holdLock(MasterProcedureEnv env)
```
    Overrides:
    
    holdLock in class org.apache.hadoop.hbase.procedure2.Procedure<MasterProcedureEnv>

Class LockProcedure

Nested Class Summary

Nested classes/interfaces inherited from class org.apache.hadoop.hbase.procedure2.Procedure

Nested classes/interfaces inherited from interface org.apache.hadoop.hbase.master.procedure.TableProcedureInterface

Field Summary

Fields inherited from class org.apache.hadoop.hbase.procedure2.Procedure

Constructor Summary

Method Summary

Methods inherited from class org.apache.hadoop.hbase.procedure2.Procedure

Methods inherited from class java.lang.Object

Field Detail

DEFAULT_REMOTE_LOCKS_TIMEOUT_MS

REMOTE_LOCKS_TIMEOUT_MS_CONF

DEFAULT_LOCAL_MASTER_LOCKS_TIMEOUT_MS

LOCAL_MASTER_LOCKS_TIMEOUT_MS_CONF

Constructor Detail

LockProcedure

LockProcedure

LockProcedure

LockProcedure

Method Detail

getTableName

getTableOperationType

updateHeartBeat

setTimeoutFailure

unlock

execute

rollback

abort

serializeStateData

deserializeStateData

acquireLock

releaseLock

beforeReplay

toStringClassDetails

getType

getDescription

isLocked

holdLock