org.opendaylight.mdsal.dom.spi.store

Interface DOMStoreReadTransaction

All Superinterfaces:

AutoCloseable, DOMStoreTransaction, org.opendaylight.yangtools.concepts.Identifiable<Object>

All Known Subinterfaces:

DOMStoreReadWriteTransaction

All Known Implementing Classes:

SnapshotBackedReadTransaction, SnapshotBackedReadWriteTransaction

public interface DOMStoreReadTransaction
extends DOMStoreTransaction

Method Summary

Modifier and Type	Method and Description
com.google.common.util.concurrent.FluentFuture<Boolean>	exists(org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier path) Checks if data is available in the logical data store located at provided path.
com.google.common.util.concurrent.FluentFuture<Optional<org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode<?,?>>>	read(org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier path) Reads data from provided logical data store located at provided path.

Methods inherited from interface org.opendaylight.mdsal.dom.spi.store.DOMStoreTransaction

close, getIdentifier

Method Detail

read

com.google.common.util.concurrent.FluentFuture<Optional<org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode<?,?>>> read(org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier path)

Reads data from provided logical data store located at provided path.

Parameters:

path - Path which uniquely identifies subtree which client want to read

Returns:

a FluentFuture containing the result of the read. The Future blocks until the commit operation is complete. Once complete:

• If the data at the supplied path exists, the Future returns an Optional object containing the data.
• If the data at the supplied path does not exist, the Future returns Optional.empty().
• If the read of the data fails, the Future will fail with a ReadFailedException or an exception derived from ReadFailedException.

exists

com.google.common.util.concurrent.FluentFuture<Boolean> exists(org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier path)

Checks if data is available in the logical data store located at provided path.

Note: a successful result from this method makes no guarantee that a subsequent call to read(org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier) will succeed. It is possible that the data resides in a data store on a remote node and, if that node goes down or a network failure occurs, a subsequent read would fail. Another scenario is if the data is deleted in between the calls to exists and read

Parameters:

path - Path which uniquely identifies subtree which client want to check existence of

Returns:

a FluentFuture containing the result of the check.

• If the data at the supplied path exists, the Future returns a Boolean whose value is true, false otherwise
• If checking for the data fails, the Future will fail with a ReadFailedException or an exception derived from ReadFailedException.