public interface Spanner extends Service<SpannerOptions>, AutoCloseableAn interface for Cloud Spanner. Typically, there would only be one instance of this for the lifetime of the application which must be closed by invoking #close() when it is no longer needed. Failure to do so may result in leaking session resources and exhausting session quota.
Methods
close()
public abstract void close()Closes all the clients associated with this instance and frees up all the resources. This
method will block until it can clean up all the resources. Specifically, it deletes all the
underlying sessions (which involves rpcs) and closes all the gRPC channels. Once this method
called, this object is no longer usable. It is strongly advised to call this method when you
are done with the Spanner object, typically when your application shuts down. There is
a hard limit on number of sessions in Cloud Spanner and not calling this method can lead to
unused sessions piling up on the backend.
createDatabaseAdminClient()
public default DatabaseAdminClient createDatabaseAdminClient()Returns a com.google.cloud.spanner.admin.database.v1.DatabaseAdminClient to execute admin operations on Cloud Spanner databases. This method always creates a new instance of com.google.cloud.spanner.admin.database.v1.DatabaseAdminClient which is an AutoCloseable resource. For optimising the number of clients, caller may choose to cache the clients instead of repeatedly invoking this method and creating new instances.
| Returns | |
|---|---|
| Type | Description |
DatabaseAdminClient |
com.google.cloud.spanner.admin.database.v1.DatabaseAdminClient |
createInstanceAdminClient()
public default InstanceAdminClient createInstanceAdminClient()Returns a com.google.cloud.spanner.admin.instance.v1.InstanceAdminClient to execute admin operations on Cloud Spanner databases. This method always creates a new instance of com.google.cloud.spanner.admin.instance.v1.InstanceAdminClient which is an AutoCloseable resource. For optimising the number of clients, caller may choose to cache the clients instead of repeatedly invoking this method and creating new instances.
| Returns | |
|---|---|
| Type | Description |
InstanceAdminClient |
com.google.cloud.spanner.admin.instance.v1.InstanceAdminClient |
getAsyncExecutorProvider()
public abstract ExecutorProvider getAsyncExecutorProvider()| Returns | |
|---|---|
| Type | Description |
ExecutorProvider |
the ExecutorProvider that is used for asynchronous queries and operations. |
getBatchClient(DatabaseId db)
public abstract BatchClient getBatchClient(DatabaseId db)Returns a BatchClient to do batch operations on Cloud Spanner databases. Batch client
is useful when one wants to read/query a large amount of data from Cloud Spanner across
multiple processes, even across different machines. It allows to create partitions of Cloud
Spanner database and then read/query over each partition independently yet at the same
snapshot.
For all other use cases, DatabaseClient is more appropriate and performant.
SpannerOptions options = SpannerOptions.newBuilder().build();
Spanner spanner = options.getService();
final String project = "test-project";
final String instance = "test-instance";
final String database = "example-db";
DatabaseId db =
DatabaseId.of(project, instance, database);
BatchClient batchClient = spanner.getBatchClient(db);
| Parameter | |
|---|---|
| Name | Description |
db |
DatabaseId |
| Returns | |
|---|---|
| Type | Description |
BatchClient |
|
getDatabaseAdminClient()
public abstract DatabaseAdminClient getDatabaseAdminClient()Returns a DatabaseAdminClient to execute admin operations on Cloud Spanner databases.
| Returns | |
|---|---|
| Type | Description |
DatabaseAdminClient |
|
getDatabaseClient(DatabaseId db)
public abstract DatabaseClient getDatabaseClient(DatabaseId db)Returns a DatabaseClient for the given database. It uses a pool of sessions to talk to
the database.
SpannerOptions options = SpannerOptions.newBuilder().build();
Spanner spanner = options.getService();
final String project = "test-project";
final String instance = "test-instance";
final String database = "example-db";
DatabaseId db =
DatabaseId.of(project, instance, database);
DatabaseClient dbClient = spanner.getDatabaseClient(db);
| Parameter | |
|---|---|
| Name | Description |
db |
DatabaseId |
| Returns | |
|---|---|
| Type | Description |
DatabaseClient |
|
getInstanceAdminClient()
public abstract InstanceAdminClient getInstanceAdminClient()Returns an InstanceAdminClient to execute admin operations on Cloud Spanner instances.
| Returns | |
|---|---|
| Type | Description |
InstanceAdminClient |
|
isClosed()
public abstract boolean isClosed()| Returns | |
|---|---|
| Type | Description |
boolean |
|