Package org.apache.hadoop.hbase.procedure2.store

Class InMemoryProcedureIterator

java.lang.Object

org.apache.hadoop.hbase.procedure2.store.InMemoryProcedureIterator

All Implemented Interfaces:

ProcedureStore.ProcedureIterator

@Private
public class InMemoryProcedureIterator
extends Object
implements ProcedureStore.ProcedureIterator

A procedure iterator which holds all the procedure protos in memory. For fast access.

Field Summary

Fields

Modifier and Type	Field	Description
private ProtoAndProcedure	current
private Iterator<ProtoAndProcedure>	iter
private final List<ProtoAndProcedure>	procs

Constructor Summary

Constructors

Constructor	Description
InMemoryProcedureIterator(List<ProtoAndProcedure> procs)

Method Summary

Modifier and Type	Method	Description
private void	checkNext()
boolean	hasNext()	Returns true if the iterator has more elements.
boolean	isNextFinished()	Calling this method does not need to convert the protobuf message to the Procedure class, so if it returns true we can call ProcedureStore.ProcedureIterator.skipNext() to skip the procedure without deserializing.
private void	moveToNext()
Procedure<?>	next()	Returns the next procedure in the iteration.
void	reset()	Reset the Iterator by seeking to the beginning of the list.
void	skipNext()	Skip the next procedure

Methods inherited from class java.lang.Object

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

Field Details

procs

private final List<ProtoAndProcedure> procs

iter

private Iterator<ProtoAndProcedure> iter

current

private ProtoAndProcedure current

Constructor Details

InMemoryProcedureIterator

public InMemoryProcedureIterator(List<ProtoAndProcedure> procs)

Method Details

reset

public void reset()

Description copied from interface: ProcedureStore.ProcedureIterator

Reset the Iterator by seeking to the beginning of the list.

Specified by:

reset in interface ProcedureStore.ProcedureIterator

hasNext

public boolean hasNext()

Description copied from interface: ProcedureStore.ProcedureIterator

Returns true if the iterator has more elements. (In other words, returns true if next() would return a Procedure rather than throwing an exception.)

Specified by:

hasNext in interface ProcedureStore.ProcedureIterator

Returns:

true if the iterator has more procedures

checkNext

private void checkNext()

isNextFinished

public boolean isNextFinished()

Description copied from interface: ProcedureStore.ProcedureIterator

Calling this method does not need to convert the protobuf message to the Procedure class, so if it returns true we can call ProcedureStore.ProcedureIterator.skipNext() to skip the procedure without deserializing. This could increase the performance.

Specified by:

isNextFinished in interface ProcedureStore.ProcedureIterator

Returns:

true if the iterator next element is a completed procedure.

moveToNext

private void moveToNext()

skipNext

public void skipNext()

Description copied from interface: ProcedureStore.ProcedureIterator

Skip the next procedure

This method is used to skip the deserializing of the procedure to increase performance, as when calling next we need to convert the protobuf message to the Procedure class.

Specified by:

skipNext in interface ProcedureStore.ProcedureIterator

next

public Procedure<?> next()
                  throws IOException

Description copied from interface: ProcedureStore.ProcedureIterator

Returns the next procedure in the iteration.

Specified by:

next in interface ProcedureStore.ProcedureIterator

Returns:

the next procedure in the iteration.

Throws:

IOException - if there was an error fetching/deserializing the procedure