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/*
* Copyright 2020 Google LLC
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.google.cloud.spanner;
import com.google.api.core.ApiFuture;
import com.google.cloud.Timestamp;
import io.grpc.Status.Code;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.Executor;
public interface AsyncRunner {
/**
* Functional interface for executing a read/write transaction asynchronously that returns a
* result of type R.
*/
@FunctionalInterface
interface AsyncWork {
/**
* Performs a single transaction attempt. All reads/writes should be performed using {@code
* txn}.
*
* Implementations of this method should not attempt to commit the transaction directly:
* returning normally will result in the runner attempting to commit the transaction once the
* returned future completes, retrying on abort.
*
*
In most cases, the implementation will not need to catch {@code SpannerException}s from
* Spanner operations, instead letting these propagate to the framework. The transaction runner
* will take appropriate action based on the type of exception. In particular, implementations
* should never catch an exception of type {@link Code#ABORTED}: these indicate that some reads
* may have returned inconsistent data and the transaction attempt must be aborted.
*
* @param txn the transaction
* @return future over the result of the work
*/
ApiFuture doWorkAsync(TransactionContext txn);
}
/** Executes a read/write transaction asynchronously using the given executor. */
ApiFuture runAsync(AsyncWork work, Executor executor);
/**
* Returns the timestamp at which the transaction committed. {@link ApiFuture#get()} will throw an
* {@link ExecutionException} if the transaction did not commit.
*/
ApiFuture getCommitTimestamp();
/**
* Returns the {@link CommitResponse} of this transaction. {@link ApiFuture#get()} throws an
* {@link ExecutionException} if the transaction did not commit.
*/
ApiFuture getCommitResponse();
}