X-Git-Url: https://git.opendaylight.org/gerrit/gitweb?a=blobdiff_plain;f=dom%2Fmdsal-dom-api%2Fsrc%2Fmain%2Fjava%2Forg%2Fopendaylight%2Fmdsal%2Fdom%2Fapi%2FDOMDataBroker.java;h=6654fbdab5bd3fd46df5784281325e4c191b4759;hb=7e9012b9820ed399a93d1f302dfa5c0e05583493;hp=ddd158a792933a8aa680493905da16109dfe7525;hpb=5445382e4f54d1a0b14ed2ce7e698f48467714f8;p=mdsal.git diff --git a/dom/mdsal-dom-api/src/main/java/org/opendaylight/mdsal/dom/api/DOMDataBroker.java b/dom/mdsal-dom-api/src/main/java/org/opendaylight/mdsal/dom/api/DOMDataBroker.java index ddd158a792..6654fbdab5 100644 --- a/dom/mdsal-dom-api/src/main/java/org/opendaylight/mdsal/dom/api/DOMDataBroker.java +++ b/dom/mdsal-dom-api/src/main/java/org/opendaylight/mdsal/dom/api/DOMDataBroker.java @@ -5,49 +5,92 @@ * terms of the Eclipse Public License v1.0 which accompanies this distribution, * and is available at http://www.eclipse.org/legal/epl-v10.html */ - package org.opendaylight.mdsal.dom.api; -import org.opendaylight.controller.md.sal.common.api.data.AsyncDataBroker; -import org.opendaylight.controller.md.sal.common.api.data.TransactionChainFactory; -import org.opendaylight.controller.md.sal.common.api.data.TransactionChainListener; -import org.opendaylight.controller.sal.core.api.BrokerService; -import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier; +import org.eclipse.jdt.annotation.NonNullByDefault; +import org.opendaylight.yangtools.concepts.Registration; import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode; /** - * Data Broker which provides data transaction and data change listener functionality - * using {@link NormalizedNode} data format. + * Data Broker which provides data transaction and data change listener functionality using {@link NormalizedNode}. + * + *

+ * All operations on the data tree are performed via one of the transactions: + *

+ * + *

+ * 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. * - * This interface is type capture of generic interfaces and returns type captures - * of results for client-code convenience. + *

+ * For a detailed explanation of how transaction are isolated and how transaction-local changes are + * committed to global data tree, see {@link DOMDataTreeReadTransaction}, {@link DOMDataTreeWriteTransaction} + * and {@link DOMDataTreeWriteTransaction#commit()}. * + * + *

+ * 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. + * + *

+ * Implementation Note: This interface is not intended to be implemented by users of MD-SAL, + * but only to be consumed by them. */ -public interface DOMDataBroker extends - AsyncDataBroker, DOMDataChangeListener>, - TransactionChainFactory>, BrokerService, DOMExtensibleService { - +@NonNullByDefault +public interface DOMDataBroker extends DOMService, DOMTransactionFactory { /** - * {@inheritDoc} + * Type capture of a {@link DOMService.Extension} applicable to {@link DOMDataBroker} implementations. */ - @Override - DOMDataReadOnlyTransaction newReadOnlyTransaction(); + interface Extension extends DOMService.Extension { + // Marker interface + } /** - * {@inheritDoc} + * Create a new transaction chain. The chain will be initialized to read from its backing datastore, with + * no outstanding transaction. + * + * @return A new transaction chain. */ - @Override - DOMDataReadWriteTransaction newReadWriteTransaction(); + DOMTransactionChain createTransactionChain(); /** - * {@inheritDoc} + * Create a new transaction chain. The chain will be initialized to read from its backing datastore, with + * no outstanding transaction. + * + *

+ * Unlike {@link #createTransactionChain()}, 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. + * + *

+ * When transactions are merged, {@link DOMTransactionChain#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. + * + * @return A new transaction chain. */ - @Override - DOMDataWriteTransaction newWriteOnlyTransaction(); + DOMTransactionChain createMergingTransactionChain(); /** - * {@inheritDoc} + * Optional support for allowing a {@link DOMDataTreeCommitCohort} to participate in the process of committing + * {@link DOMDataTreeWriteTransaction}s. */ - @Override - DOMTransactionChain createTransactionChain(TransactionChainListener listener); + interface CommitCohortExtension extends Extension { + /** + * Register commit cohort which will participate in three-phase commit protocols of + * {@link DOMDataTreeWriteTransaction} in data broker associated with this instance of extension. + * + * @param path Subtree path on which commit cohort operates. + * @param cohort A {@link DOMDataTreeCommitCohort} + * @return A {@link Registration} + * @throws NullPointerException if any argument is {@code null} + */ + Registration registerCommitCohort(DOMDataTreeIdentifier path, DOMDataTreeCommitCohort cohort); + } }