org.apache.ratis.statemachine

接口 StateMachine.DataApi

封闭接口:

StateMachine

public static interface StateMachine.DataApi

An optional API for managing data outside the raft log. For data intensive applications, it can be more efficient to implement this API in order to support zero buffer coping and a light-weighted raft log.

字段概要

字段

限定符和类型	字段和说明
static StateMachine.DataApi	DEFAULT A noop implementation of StateMachine.DataApi.

方法概要

限定符和类型	方法和说明
default CompletableFuture<Void>	flush(long logIndex) Flush the state machine data till the given log index.
default CompletableFuture<?>	link(StateMachine.DataStream stream, org.apache.ratis.proto.RaftProtos.LogEntryProto entry) Link asynchronously the given stream with the given log entry.
default CompletableFuture<org.apache.ratis.thirdparty.com.google.protobuf.ByteString>	read(org.apache.ratis.proto.RaftProtos.LogEntryProto entry) Read asynchronously the state machine data from this state machine.
default CompletableFuture<org.apache.ratis.thirdparty.com.google.protobuf.ByteString>	read(org.apache.ratis.proto.RaftProtos.LogEntryProto entry, TransactionContext context) Read asynchronously the state machine data from this state machine.
default CompletableFuture<StateMachine.DataStream>	stream(RaftClientRequest request) Create asynchronously a StateMachine.DataStream to stream state machine data.
default CompletableFuture<Void>	truncate(long logIndex) Truncates asynchronously the state machine data to the given log index.
default CompletableFuture<?>	write(org.apache.ratis.proto.RaftProtos.LogEntryProto entry) Write asynchronously the state machine data in the given log entry to this state machine.
default CompletableFuture<?>	write(org.apache.ratis.proto.RaftProtos.LogEntryProto entry, TransactionContext context) Write asynchronously the state machine data in the given log entry to this state machine.

字段详细资料

DEFAULT

static final StateMachine.DataApi DEFAULT

A noop implementation of StateMachine.DataApi.

方法详细资料

read

default CompletableFuture<org.apache.ratis.thirdparty.com.google.protobuf.ByteString> read(org.apache.ratis.proto.RaftProtos.LogEntryProto entry)

Read asynchronously the state machine data from this state machine.

返回:

a future for the read task.

read

default CompletableFuture<org.apache.ratis.thirdparty.com.google.protobuf.ByteString> read(org.apache.ratis.proto.RaftProtos.LogEntryProto entry,
                                                                                           TransactionContext context)

Read asynchronously the state machine data from this state machine.

返回:

a future for the read task.

write

default CompletableFuture<?> write(org.apache.ratis.proto.RaftProtos.LogEntryProto entry)

Write asynchronously the state machine data in the given log entry to this state machine.

返回:

a future for the write task

write

default CompletableFuture<?> write(org.apache.ratis.proto.RaftProtos.LogEntryProto entry,
                                   TransactionContext context)

Write asynchronously the state machine data in the given log entry to this state machine.

返回:

a future for the write task

stream

default CompletableFuture<StateMachine.DataStream> stream(RaftClientRequest request)

Create asynchronously a StateMachine.DataStream to stream state machine data. The state machine may use the first message (i.e. request.getMessage()) as the header to create the stream.

返回:

a future of the stream.

link

default CompletableFuture<?> link(StateMachine.DataStream stream,
                                  org.apache.ratis.proto.RaftProtos.LogEntryProto entry)

Link asynchronously the given stream with the given log entry. The given stream can be null if it is unavailable due to errors. In such case, the state machine may either recover the data by itself or complete the returned future exceptionally.

参数:

stream - the stream, which can possibly be null, to be linked.

entry - the log entry to be linked.

返回:

a future for the link task.

flush

default CompletableFuture<Void> flush(long logIndex)

Flush the state machine data till the given log index.

参数:

logIndex - The log index to flush.

返回:

a future for the flush task.

truncate

default CompletableFuture<Void> truncate(long logIndex)

Truncates asynchronously the state machine data to the given log index. It is a noop if the corresponding log entry does not have state machine data.

参数:

logIndex - The last log index after truncation.

返回:

a future for truncate task.