org.apache.hadoop.hbase.procedure2

类 StateMachineProcedure<TEnvironment,TState>

java.lang.Object

org.apache.hadoop.hbase.procedure2.Procedure<TEnvironment>

org.apache.hadoop.hbase.procedure2.StateMachineProcedure<TEnvironment,TState>

所有已实现的接口:

Comparable<Procedure>

@InterfaceAudience.Private
@InterfaceStability.Evolving
public abstract class StateMachineProcedure<TEnvironment,TState>
extends Procedure<TEnvironment>

Procedure described by a series of steps. The procedure implementor must have an enum of 'states', describing the various step of the procedure. Once the procedure is running, the procedure-framework will call executeFromState() using the 'state' provided by the user. The first call to executeFromState() will be performed with 'state = null'. The implementor can jump between states using setNextState(MyStateEnum.ordinal()). The rollback will call rollbackState() for each state that was executed, in reverse order.

嵌套类概要

嵌套类

限定符和类型	类和说明
protected static class	StateMachineProcedure.Flow

构造器概要

构造器

构造器和说明
StateMachineProcedure()

方法概要

方法

限定符和类型	方法和说明
protected void	addChildProcedure(Procedure... subProcedure) Add a child procedure to execute
protected void	deserializeStateData(InputStream stream) Called on store load to allow the user to decode the previously serialized state.
protected Procedure[]	execute(TEnvironment env) The main code of the procedure.
protected abstract StateMachineProcedure.Flow	executeFromState(TEnvironment env, TState state) called to perform a single step of the specified 'state' of the procedure
protected abstract TState	getInitialState() Return the initial state object that will be used for the first call to executeFromState().
protected abstract TState	getState(int stateId) Convert an ordinal (or state id) to an Enum (or more descriptive) state object.
protected abstract int	getStateId(TState state) Convert the Enum (or more descriptive) state object to an ordinal (or state id).
protected boolean	isYieldAfterExecutionStep(TEnvironment env) By default, the executor will try ro run procedures start to finish.
protected boolean	isYieldBeforeExecuteFromState(TEnvironment env, TState state) By default, the executor will try ro run all the steps of the procedure start to finish.
protected void	rollback(TEnvironment env) The code to undo what done by the execute() code.
protected abstract void	rollbackState(TEnvironment env, TState state) called to perform the rollback of the specified state
protected void	serializeStateData(OutputStream stream) The user-level code of the procedure may have some state to persist (e.g. input arguments) to be able to resume on failure.
protected void	setNextState(TState state) Set the next state for the procedure.
protected void	toStringState(StringBuilder builder) Called from Procedure.toString() when interpolating Procedure state

从类继承的方法 org.apache.hadoop.hbase.procedure2.Procedure

abort, acquireLock, addStackIndex, beforeReplay, childrenCountDown, compareTo, completionCleanup, convert, convert, createProcedureInfo, doExecute, doRollback, elapsedTime, getException, getLastUpdate, getNonceKey, getOwner, getParentProcId, getProcId, getProcIdHashCode, getResult, getRootProcedureId, getStackIndexes, getStartTime, getState, getTimeout, getTimeRemaining, hasChildren, hasException, hasOwner, hasParent, hasTimeout, incChildrenLatch, isFailed, isFinished, isRunnable, isSuccess, isWaiting, newInstance, releaseLock, removeStackIndex, setAbortFailure, setChildrenLatch, setFailure, setFailure, setNonceKey, setOwner, setParentProcId, setProcId, setResult, setStackIndexes, setStartTime, setState, setTimeout, setTimeoutFailure, shouldWaitClientAck, toString, toStringClass, toStringClassDetails, toStringDetails, toStringSimpleSB, updateTimestamp, validateClass, wasExecuted

从类继承的方法 java.lang.Object

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

构造器详细资料

StateMachineProcedure

public StateMachineProcedure()

方法详细资料

executeFromState

protected abstract StateMachineProcedure.Flow executeFromState(TEnvironment env,
                                          TState state)
                                                        throws ProcedureYieldException,
                                                               InterruptedException

called to perform a single step of the specified 'state' of the procedure

参数:

state - state to execute

返回:

Flow.NO_MORE_STATE if the procedure is completed, Flow.HAS_MORE_STATE if there is another step.

抛出:

ProcedureYieldException

InterruptedException

rollbackState

protected abstract void rollbackState(TEnvironment env,
                 TState state)
                               throws IOException,
                                      InterruptedException

called to perform the rollback of the specified state

参数:

state - state to rollback

抛出:

IOException - temporary failure, the rollback will retry later

InterruptedException

getState

protected abstract TState getState(int stateId)

Convert an ordinal (or state id) to an Enum (or more descriptive) state object.

参数:

stateId - the ordinal() of the state enum (or state id)

返回:

the state enum object

getStateId

protected abstract int getStateId(TState state)

Convert the Enum (or more descriptive) state object to an ordinal (or state id).

参数:

state - the state enum object

返回:

stateId the ordinal() of the state enum (or state id)

getInitialState

protected abstract TState getInitialState()

Return the initial state object that will be used for the first call to executeFromState().

返回:

the initial state enum object

setNextState

protected void setNextState(TState state)

Set the next state for the procedure.

参数:

state - the state enum object

isYieldBeforeExecuteFromState

protected boolean isYieldBeforeExecuteFromState(TEnvironment env,
                                    TState state)

By default, the executor will try ro run all the steps of the procedure start to finish. Return true to make the executor yield between execution steps to give other procedures time to run their steps.

参数:

state - the state we are going to execute next.

返回:

Return true if the executor should yield before the execution of the specified step. Defaults to return false.

addChildProcedure

protected void addChildProcedure(Procedure... subProcedure)

Add a child procedure to execute

参数:

subProcedure - the child procedure

execute

protected Procedure[] execute(TEnvironment env)
                       throws ProcedureYieldException,
                              InterruptedException

从类复制的说明: Procedure

The main code of the procedure. It must be idempotent since execute() may be called multiple time in case of machine failure in the middle of the execution.

指定者:

execute 在类中 Procedure<TEnvironment>

参数:

env - the environment passed to the ProcedureExecutor

返回:

a set of sub-procedures or null if there is nothing else to execute.

抛出:

ProcedureYieldException - the procedure will be added back to the queue and retried later

InterruptedException - the procedure will be added back to the queue and retried later

rollback

protected void rollback(TEnvironment env)
                 throws IOException,
                        InterruptedException

从类复制的说明: Procedure

The code to undo what done by the execute() code. It is called when the procedure or one of the sub-procedure failed or an abort was requested. It should cleanup all the resources created by the execute() call. The implementation must be idempotent since rollback() may be called multiple time in case of machine failure in the middle of the execution.

指定者:

rollback 在类中 Procedure<TEnvironment>

参数:

env - the environment passed to the ProcedureExecutor

抛出:

IOException - temporary failure, the rollback will retry later

InterruptedException - the procedure will be added back to the queue and retried later

isYieldAfterExecutionStep

protected boolean isYieldAfterExecutionStep(TEnvironment env)

从类复制的说明: Procedure

By default, the executor will try ro run procedures start to finish. Return true to make the executor yield between each execution step to give other procedures time to run their steps.

覆盖:

isYieldAfterExecutionStep 在类中 Procedure<TEnvironment>

参数:

env - the environment passed to the ProcedureExecutor

返回:

Return true if the executor should yield on completion of an execution step. Defaults to return false.

toStringState

protected void toStringState(StringBuilder builder)

从类复制的说明: Procedure

Called from Procedure.toString() when interpolating Procedure state

覆盖:

toStringState 在类中 Procedure<TEnvironment>

参数:

builder - Append current ProcedureProtos.ProcedureState

serializeStateData

protected void serializeStateData(OutputStream stream)
                           throws IOException

从类复制的说明: Procedure

The user-level code of the procedure may have some state to persist (e.g. input arguments) to be able to resume on failure.

指定者:

serializeStateData 在类中 Procedure<TEnvironment>

参数:

stream - the stream that will contain the user serialized data

抛出:

IOException

deserializeStateData

protected void deserializeStateData(InputStream stream)
                             throws IOException

从类复制的说明: Procedure

Called on store load to allow the user to decode the previously serialized state.

指定者:

deserializeStateData 在类中 Procedure<TEnvironment>

参数:

stream - the stream that contains the user serialized data

抛出:

IOException