@@ -471,13 +471,17 @@ public ServiceRpc create(SpannerOptions options) {
private static final AtomicInteger DEFAULT_POOL_COUNT = new AtomicInteger ();
/** {@link ExecutorProvider} that is used for {@link AsyncResultSet}. */
interface CloseableExecutorProvider extends ExecutorProvider , AutoCloseable {
public interface CloseableExecutorProvider extends ExecutorProvider , AutoCloseable {
/** Overridden to suppress the throws declaration of the super interface. */
@ Override
void close ();
}
static class FixedCloseableExecutorProvider implements CloseableExecutorProvider {
/**
* Implementation of {@link CloseableExecutorProvider} that uses a fixed single {@link
* ScheduledExecutorService}.
*/
public static class FixedCloseableExecutorProvider implements CloseableExecutorProvider {
private final ScheduledExecutorService executor ;
private FixedCloseableExecutorProvider (ScheduledExecutorService executor ) {
@@ -500,7 +504,7 @@ public boolean shouldAutoClose() {
}
/** Creates a FixedCloseableExecutorProvider. */
static FixedCloseableExecutorProvider create (ScheduledExecutorService executor ) {
public static FixedCloseableExecutorProvider create (ScheduledExecutorService executor ) {
return new FixedCloseableExecutorProvider (executor );
}
}
@@ -516,8 +520,19 @@ static CloseableExecutorProvider createDefaultAsyncExecutorProvider() {
return createAsyncExecutorProvider (8 , 60L , TimeUnit .SECONDS );
}
@ VisibleForTesting
static CloseableExecutorProvider createAsyncExecutorProvider (
/**
* Creates a {@link CloseableExecutorProvider} that can be used as an {@link ExecutorProvider} for
* the async API. The {@link ExecutorProvider} will lazily create up to poolSize threads. The
* backing threads will automatically be shutdown if they have not been used during the keep-alive
* time. The backing threads are created as daemon threads.
*
* @param poolSize the maximum number of threads to create in the pool
* @param keepAliveTime the time that an unused thread in the pool should be kept alive
* @param unit the time unit used for the keepAliveTime
* @return a {@link CloseableExecutorProvider} that can be used for {@link
* SpannerOptions.Builder#setAsyncExecutorProvider(CloseableExecutorProvider)}
*/
public static CloseableExecutorProvider createAsyncExecutorProvider (
int poolSize , long keepAliveTime , TimeUnit unit ) {
String format =
String .format ("spanner-async-pool-%d-thread-%%d" , DEFAULT_POOL_COUNT .incrementAndGet ());
@@ -1018,6 +1033,26 @@ public Builder setCompressorName(@Nullable String compressorName) {
return this ;
}
/**
* Sets the {@link ExecutorProvider} to use for high-level async calls that need an executor,
* such as fetching results for an {@link AsyncResultSet}.
*
* <p>Async methods will use a sensible default if no custom {@link ExecutorProvider} has been
* set. The default {@link ExecutorProvider} uses a cached thread pool containing a maximum of 8
* threads. The pool is lazily initialized and will not create any threads if the user
* application does not use any async methods. It will also scale down the thread usage if the
* async load allows for that.
*
* <p>Call {@link SpannerOptions#createAsyncExecutorProvider(int, long, TimeUnit)} to create a
* provider with a custom pool size or call {@link
* FixedCloseableExecutorProvider#create(ScheduledExecutorService)} to create a {@link
* CloseableExecutorProvider} from a standard Java {@link ScheduledExecutorService}.
*/
public Builder setAsyncExecutorProvider (CloseableExecutorProvider provider ) {
this .asyncExecutorProvider = provider ;
return this ;
}
/**
* Specifying this will allow the client to prefetch up to {@code prefetchChunks} {@code
* PartialResultSet} chunks for each read and query. The data size of each chunk depends on the
@@ -1198,7 +1233,7 @@ public QueryOptions getDefaultQueryOptions(DatabaseId databaseId) {
return options ;
}
CloseableExecutorProvider getAsyncExecutorProvider () {
public CloseableExecutorProvider getAsyncExecutorProvider () {
return asyncExecutorProvider ;
}
