*/
package org.opendaylight.mdsal.binding.api;
-import org.opendaylight.mdsal.common.api.AsyncDataBroker;
-import org.opendaylight.mdsal.common.api.LogicalDatastoreType;
-import org.opendaylight.mdsal.common.api.TransactionChainFactory;
-import org.opendaylight.mdsal.common.api.TransactionChainListener;
-
-import org.opendaylight.yangtools.concepts.ListenerRegistration;
-import org.opendaylight.yangtools.yang.binding.DataObject;
-import org.opendaylight.yangtools.yang.binding.InstanceIdentifier;
+import org.eclipse.jdt.annotation.NonNull;
/**
* Provides access to a conceptual data tree store and also provides the ability to
* subscribe for changes to data under a given branch of the tree.
+ *
+ * <p>
+ * All operations on the data tree are performed via one of the transactions:
+ * <ul>
+ * <li>Read-Only - allocated using {@link #newReadOnlyTransaction()}
+ * <li>Write-Only - allocated using {@link #newWriteOnlyTransaction()}
+ * </ul>
+ *
+ * <p>
+ * These transactions provide a stable isolated view of data tree, which is guaranteed to be not
+ * affected by other concurrent transactions, until transaction is committed.
+ *
* <p>
- * For more information on usage, please see the documentation in {@link AsyncDataBroker}.
+ * For a detailed explanation of how transaction are isolated and how transaction-local changes are
+ * committed to global data tree, see {@link ReadTransaction}, {@link WriteTransaction}
+ * and {@link WriteTransaction#commit()}.
*
- * @see AsyncDataBroker
- * @see TransactionChainFactory
+ * <p>
+ * It is strongly recommended to use the type of transaction, which provides only the minimal
+ * capabilities you need. This allows for optimizations at the data broker / data store level. For
+ * example, implementations may optimize the transaction for reading if they know ahead of time that
+ * you only need to read data - such as not keeping additional meta-data, which may be required for
+ * write transactions.
+ *
+ * <p>
+ * <b>Implementation Note:</b> This interface is not intended to be implemented by users of MD-SAL,
+ * but only to be consumed by them.
*/
-public interface DataBroker extends AsyncDataBroker<InstanceIdentifier<?>, DataObject>,
- TransactionChainFactory<InstanceIdentifier<?>, DataObject>, TransactionFactory, BindingService, DataTreeChangeService {
- /**
- * {@inheritDoc}
- */
- @Override
- ReadTransaction newReadOnlyTransaction();
-
+public interface DataBroker extends BindingService, TransactionFactory, DataTreeChangeService {
/**
- * {@inheritDoc}
+ * Create a new transaction chain. The chain will be initialized to read from its backing datastore, with
+ * no outstanding transaction. Listener will be registered to handle chain-level events.
+ *
+ * @param listener Transaction chain event listener
+ * @return A new transaction chain.
*/
- @Override
- WriteTransaction newWriteOnlyTransaction();
+ @NonNull TransactionChain createTransactionChain(@NonNull TransactionChainListener listener);
/**
- * {@inheritDoc}
+ * Create a new transaction chain. The chain will be initialized to read from its backing datastore, with
+ * no outstanding transaction. Listener will be registered to handle chain-level events.
+ *
+ * <p>
+ * Unlike {@link #createTransactionChain(TransactionChainListener)}, the transaction chain returned by this
+ * method is allowed to merge individual transactions into larger chunks. When transactions are merged, the results
+ * must be indistinguishable from the result of all operations having been performed on a single transaction.
+ *
+ * <p>
+ * When transactions are merged, {@link TransactionChain#newReadOnlyTransaction()} may actually be backed by
+ * a read-write transaction, hence an additional restriction on API use is that multiple read-only transactions
+ * may not be open at the same time.
+ *
+ * @param listener Transaction chain event listener
+ * @return A new transaction chain.
*/
- @Override
- BindingTransactionChain createTransactionChain(TransactionChainListener listener);
+ @NonNull TransactionChain createMergingTransactionChain(@NonNull TransactionChainListener listener);
}