5dd8bd3e3ed7fcb0b42b3fd3acb6a32f2f229d65
[controller.git] / opendaylight / md-sal / sal-distributed-datastore / src / main / java / org / opendaylight / controller / cluster / databroker / AbstractDOMBrokerWriteTransaction.java
1 /*
2  * Copyright (c) 2015 Cisco Systems, Inc. and others.  All rights reserved.
3  *
4  * This program and the accompanying materials are made available under the
5  * terms of the Eclipse Public License v1.0 which accompanies this distribution,
6  * and is available at http://www.eclipse.org/legal/epl-v10.html
7  */
8
9 package org.opendaylight.controller.cluster.databroker;
10
11 import com.google.common.base.Preconditions;
12 import com.google.common.util.concurrent.CheckedFuture;
13 import com.google.common.util.concurrent.Futures;
14 import com.google.common.util.concurrent.ListenableFuture;
15 import java.util.ArrayList;
16 import java.util.Collection;
17 import java.util.Map;
18 import java.util.concurrent.Future;
19 import java.util.concurrent.atomic.AtomicReferenceFieldUpdater;
20 import org.opendaylight.controller.md.sal.common.api.TransactionStatus;
21 import org.opendaylight.controller.md.sal.common.api.data.LogicalDatastoreType;
22 import org.opendaylight.controller.md.sal.common.api.data.TransactionCommitFailedException;
23 import org.opendaylight.controller.md.sal.common.impl.service.AbstractDataTransaction;
24 import org.opendaylight.controller.md.sal.dom.api.DOMDataWriteTransaction;
25 import org.opendaylight.controller.sal.core.spi.data.DOMStoreThreePhaseCommitCohort;
26 import org.opendaylight.controller.sal.core.spi.data.DOMStoreTransactionFactory;
27 import org.opendaylight.controller.sal.core.spi.data.DOMStoreWriteTransaction;
28 import org.opendaylight.yangtools.yang.common.RpcResult;
29 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
30 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.PathArgument;
31 import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
32 import org.slf4j.Logger;
33 import org.slf4j.LoggerFactory;
34
35 public abstract class AbstractDOMBrokerWriteTransaction<T extends DOMStoreWriteTransaction>
36         extends AbstractDOMBrokerTransaction<T> implements DOMDataWriteTransaction {
37
38     @SuppressWarnings("rawtypes")
39     private static final AtomicReferenceFieldUpdater<AbstractDOMBrokerWriteTransaction, AbstractDOMTransactionFactory>
40             IMPL_UPDATER = AtomicReferenceFieldUpdater.newUpdater(AbstractDOMBrokerWriteTransaction.class,
41                     AbstractDOMTransactionFactory.class, "commitImpl");
42     @SuppressWarnings("rawtypes")
43     private static final AtomicReferenceFieldUpdater<AbstractDOMBrokerWriteTransaction, Future> FUTURE_UPDATER =
44             AtomicReferenceFieldUpdater.newUpdater(AbstractDOMBrokerWriteTransaction.class, Future.class,
45                     "commitFuture");
46     private static final Logger LOG = LoggerFactory.getLogger(AbstractDOMBrokerWriteTransaction.class);
47     private static final Future<?> CANCELLED_FUTURE = Futures.immediateCancelledFuture();
48
49     /**
50      * Implementation of real commit. It also acts as an indication that
51      * the transaction is running -- which we flip atomically using
52      * {@link #IMPL_UPDATER}.
53      */
54     private volatile AbstractDOMTransactionFactory<?> commitImpl;
55
56     /**
57      * Future task of transaction commit. It starts off as null, but is
58      * set appropriately on {@link #submit()} and {@link #cancel()} via
59      * {@link AtomicReferenceFieldUpdater#lazySet(Object, Object)}.
60      * <p/>
61      * Lazy set is safe for use because it is only referenced to in the
62      * {@link #cancel()} slow path, where we will busy-wait for it. The
63      * fast path gets the benefit of a store-store barrier instead of the
64      * usual store-load barrier.
65      */
66     private volatile Future<?> commitFuture;
67
68     protected AbstractDOMBrokerWriteTransaction(final Object identifier,
69             final Map<LogicalDatastoreType, ? extends DOMStoreTransactionFactory> storeTxFactories,
70             final AbstractDOMTransactionFactory<?> commitImpl) {
71         super(identifier, storeTxFactories);
72         this.commitImpl = Preconditions.checkNotNull(commitImpl, "commitImpl must not be null.");
73     }
74
75     @Override
76     public void put(final LogicalDatastoreType store, final YangInstanceIdentifier path,
77             final NormalizedNode<?, ?> data) {
78         checkRunning(commitImpl);
79         checkInstanceIdentifierReferencesData(path,data);
80         getSubtransaction(store).write(path, data);
81     }
82
83     private static void checkInstanceIdentifierReferencesData(final YangInstanceIdentifier path,
84             final NormalizedNode<?, ?> data) {
85         Preconditions.checkArgument(data != null, "Attempted to store null data at %s", path);
86         final PathArgument lastArg = path.getLastPathArgument();
87         Preconditions.checkArgument(
88                 lastArg == data.getIdentifier() || lastArg != null && lastArg.equals(data.getIdentifier()),
89                 "Instance identifier references %s but data identifier is %s", lastArg, data);
90     }
91
92     @Override
93     public void delete(final LogicalDatastoreType store, final YangInstanceIdentifier path) {
94         checkRunning(commitImpl);
95         getSubtransaction(store).delete(path);
96     }
97
98     @Override
99     public void merge(final LogicalDatastoreType store, final YangInstanceIdentifier path,
100             final NormalizedNode<?, ?> data) {
101         checkRunning(commitImpl);
102         checkInstanceIdentifierReferencesData(path, data);
103         getSubtransaction(store).merge(path, data);
104     }
105
106     @Override
107     public boolean cancel() {
108         final AbstractDOMTransactionFactory<?> impl = IMPL_UPDATER.getAndSet(this, null);
109         if (impl != null) {
110             LOG.trace("Transaction {} cancelled before submit", getIdentifier());
111             FUTURE_UPDATER.lazySet(this, CANCELLED_FUTURE);
112             closeSubtransactions();
113             return true;
114         }
115
116         // The transaction is in process of being submitted or cancelled. Busy-wait
117         // for the corresponding future.
118         Future<?> future;
119         do {
120             future = commitFuture;
121         }
122         while (future == null);
123
124         return future.cancel(false);
125     }
126
127     @Deprecated
128     @Override
129     public ListenableFuture<RpcResult<TransactionStatus>> commit() {
130         return AbstractDataTransaction.convertToLegacyCommitFuture(submit());
131     }
132
133     @Override
134     public CheckedFuture<Void, TransactionCommitFailedException> submit() {
135         final AbstractDOMTransactionFactory<?> impl = IMPL_UPDATER.getAndSet(this, null);
136         checkRunning(impl);
137
138         final Collection<T> txns = getSubtransactions();
139         final Collection<DOMStoreThreePhaseCommitCohort> cohorts = new ArrayList<>(txns.size());
140
141         // FIXME: deal with errors thrown by backed (ready and submit can fail in theory)
142         for (final T txn : txns) {
143             cohorts.add(txn.ready());
144         }
145
146         final CheckedFuture<Void, TransactionCommitFailedException> ret = impl.submit(this, cohorts);
147         FUTURE_UPDATER.lazySet(this, ret);
148         return ret;
149     }
150
151     private void checkRunning(final AbstractDOMTransactionFactory<?> impl) {
152         Preconditions.checkState(impl != null, "Transaction %s is no longer running", getIdentifier());
153     }
154
155 }

©2013 OpenDaylight, A Linux Foundation Collaborative Project. All Rights Reserved.
OpenDaylight is a registered trademark of The OpenDaylight Project, Inc.
Linux Foundation and OpenDaylight are registered trademarks of the Linux Foundation.
Linux is a registered trademark of Linus Torvalds.