Package com.google.cloud.datastore

Class ReadOption

java.lang.Object

com.google.cloud.datastore.ReadOption

All Implemented Interfaces:

Serializable

Direct Known Subclasses:

ReadOption.EventualConsistency, ReadOption.ReadTime

public abstract class ReadOption
extends Object
implements Serializable

Specifies options for read operations in Datastore, namely getting/fetching entities and running queries.

See Also:

• Serialized Form

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static final class	ReadOption.EventualConsistency	Specifies eventual consistency for reads from Datastore.
static class	ReadOption.QueryAndReadOptions<Q extends Query<?>>
static final class	ReadOption.ReadTime	Reads entities as they were at the given time.

Method Summary

Modifier and Type	Method	Description
static ReadOption.EventualConsistency	eventualConsistency()	Returns a ReadOption that specifies eventual consistency, allowing Datastore to return stale results from gets, fetches, and ancestor queries.
static ReadOption.ReadTime	readTime(com.google.cloud.Timestamp time)	Returns a ReadOption that specifies read time, allowing Datastore to return results from lookups and queries at a particular timestamp.
static ReadOption	transactionId(com.google.protobuf.ByteString transactionId)	Returns a ReadOption that specifies transaction id, allowing Datastore to execute a Query in this transaction.
static ReadOption	transactionId(String transactionId)	Returns a ReadOption that specifies transaction id, allowing Datastore to execute a Query in this transaction.

Methods inherited from class java.lang.Object

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

Method Details

eventualConsistency

public static ReadOption.EventualConsistency eventualConsistency()

Returns a ReadOption that specifies eventual consistency, allowing Datastore to return stale results from gets, fetches, and ancestor queries.

readTime

@BetaApi
public static ReadOption.ReadTime readTime(com.google.cloud.Timestamp time)

Returns a ReadOption that specifies read time, allowing Datastore to return results from lookups and queries at a particular timestamp. This feature is currently in private preview.

transactionId

@InternalApi
public static ReadOption transactionId(String transactionId)

Returns a ReadOption that specifies transaction id, allowing Datastore to execute a Query in this transaction.

transactionId

@InternalApi
public static ReadOption transactionId(com.google.protobuf.ByteString transactionId)

Returns a ReadOption that specifies transaction id, allowing Datastore to execute a Query in this transaction.