org.opendaylight.mdsal.dom.api

Interface DOMDataTreeReadTransaction

All Superinterfaces:

AsyncReadTransaction<org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier,org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode<?,?>>, AsyncTransaction<org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier,org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode<?,?>>, AutoCloseable, org.opendaylight.yangtools.concepts.Identifiable<Object>

All Known Subinterfaces:

DOMDataTreeReadWriteTransaction

All Known Implementing Classes:

ForwardingDOMDataReadOnlyTransaction, ForwardingDOMDataReadWriteTransaction, ShardedDOMReadTransactionAdapter, ShardedDOMReadWriteTransactionAdapter, TransactionChainReadTransaction

public interface DOMDataTreeReadTransaction
extends AsyncReadTransaction<org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier,org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode<?,?>>

A transaction that provides read access to a logical data store.

For more information on usage and examples, please see the documentation in AsyncReadTransaction.

Method Summary

Modifier and Type	Method and Description
com.google.common.util.concurrent.FluentFuture<Boolean>	exists(LogicalDatastoreType store, 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(LogicalDatastoreType store, org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier path) Reads data from provided logical data store located at the provided path.

Methods inherited from interface org.opendaylight.mdsal.common.api.AsyncReadTransaction

close

Methods inherited from interface org.opendaylight.mdsal.common.api.AsyncTransaction

getIdentifier

Method Detail

read

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

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

If the target is a subtree, then the whole subtree is read (and will be accessible from the returned data object).

Parameters:

store - Logical data store from which read should occur.

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#absent().
• 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(LogicalDatastoreType store,
                                                               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.mdsal.common.api.LogicalDatastoreType, 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:

store - Logical data store from which read should occur.

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.