opendaylight/md-sal/sal-dom-broker/src/main/java/org/opendaylight/controller/md/sal/dom/broker/impl/DOMForwardedWriteTransaction.java

   1 /*
   2  * Copyright (c) 2014 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 package org.opendaylight.controller.md.sal.dom.broker.impl;
   9
  10 import static com.google.common.base.Preconditions.checkState;
  11
  12 import javax.annotation.concurrent.GuardedBy;
  13
  14 import org.opendaylight.controller.md.sal.common.api.TransactionStatus;
  15 import org.opendaylight.controller.md.sal.common.api.data.LogicalDatastoreType;
  16 import org.opendaylight.controller.md.sal.dom.api.DOMDataWriteTransaction;
  17 import org.opendaylight.controller.sal.core.spi.data.DOMStoreThreePhaseCommitCohort;
  18 import org.opendaylight.controller.sal.core.spi.data.DOMStoreWriteTransaction;
  19 import org.opendaylight.yangtools.yang.common.RpcResult;
  20 import org.opendaylight.yangtools.yang.data.api.InstanceIdentifier;
  21 import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
  22
  23 import com.google.common.base.Preconditions;
  24 import com.google.common.collect.ImmutableList;
  25 import com.google.common.collect.ImmutableMap;
  26 import com.google.common.util.concurrent.ListenableFuture;
  27
  28 /**
  29  *
  30  *
  31  * Read-Write Transaction, which is composed of several
  32  * {@link DOMStoreWriteTransaction} transactions. Subtransaction is selected by
  33  * {@link LogicalDatastoreType} type parameter in:
  34  *
  35  * <ul>
  36  * <li>{@link #put(LogicalDatastoreType, InstanceIdentifier, NormalizedNode)}
  37  * <li>{@link #delete(LogicalDatastoreType, InstanceIdentifier)}
  38  * <li>{@link #merge(LogicalDatastoreType, InstanceIdentifier, NormalizedNode)}
  39  * </ul>
  40  * <p>
  41  * {@link #commit()} will result in invocation of
  42  * {@link DOMDataCommitImplementation#commit(org.opendaylight.controller.md.sal.dom.api.DOMDataWriteTransaction, Iterable)}
  43  * invocation with all {@link org.opendaylight.controller.sal.core.spi.data.DOMStoreThreePhaseCommitCohort} for underlying
  44  * transactions.
  45  *
  46  * @param <T>
  47  *            Subtype of {@link DOMStoreWriteTransaction} which is used as
  48  *            subtransaction.
  49  */
  50 class DOMForwardedWriteTransaction<T extends DOMStoreWriteTransaction> extends
  51         AbstractDOMForwardedCompositeTransaction<LogicalDatastoreType, T> implements DOMDataWriteTransaction {
  52
  53     /**
  54      *  Implementation of real commit.
  55      *
  56      *  Transaction can not be commited if commitImpl is null,
  57      *  so this seting this property to null is also used to
  58      *  prevent write to
  59      *  already commited / canceled transaction {@link #checkNotCanceled()
  60      *
  61      *
  62      */
  63     @GuardedBy("this")
  64     private volatile DOMDataCommitImplementation commitImpl;
  65
  66     /**
  67      *
  68      * Future task of transaction commit.
  69      *
  70      * This value is initially null, and is once updated if transaction
  71      * is commited {@link #commit()}.
  72      * If this future exists, transaction MUST not be commited again
  73      * and all modifications should fail. See {@link #checkNotCommited()}.
  74      *
  75      */
  76     @GuardedBy("this")
  77     private volatile ListenableFuture<RpcResult<TransactionStatus>> commitFuture;
  78
  79     protected DOMForwardedWriteTransaction(final Object identifier,
  80             final ImmutableMap<LogicalDatastoreType, T> backingTxs, final DOMDataCommitImplementation commitImpl) {
  81         super(identifier, backingTxs);
  82         this.commitImpl = Preconditions.checkNotNull(commitImpl, "commitImpl must not be null.");
  83     }
  84
  85     @Override
  86     public void put(final LogicalDatastoreType store, final InstanceIdentifier path, final NormalizedNode<?, ?> data) {
  87         checkNotReady();
  88         getSubtransaction(store).write(path, data);
  89     }
  90
  91     @Override
  92     public void delete(final LogicalDatastoreType store, final InstanceIdentifier path) {
  93         checkNotReady();
  94         getSubtransaction(store).delete(path);
  95     }
  96
  97     @Override
  98     public void merge(final LogicalDatastoreType store, final InstanceIdentifier path, final NormalizedNode<?, ?> data) {
  99         checkNotReady();
 100         getSubtransaction(store).merge(path, data);
 101     }
 102
 103     @Override
 104     public synchronized boolean cancel() {
 105         // Transaction is already canceled, we are safe to return true
 106         final boolean cancelationResult;
 107         if (commitImpl == null && commitFuture != null) {
 108             // Transaction is submitted, we try to cancel future.
 109             cancelationResult = commitFuture.cancel(false);
 110         } else if(commitImpl == null) {
 111             return true;
 112         } else {
 113             cancelationResult = true;
 114             commitImpl = null;
 115         }
 116         return cancelationResult;
 117
 118     }
 119
 120     @Override
 121     public synchronized ListenableFuture<RpcResult<TransactionStatus>> commit() {
 122         checkNotReady();
 123
 124         ImmutableList.Builder<DOMStoreThreePhaseCommitCohort> cohortsBuilder = ImmutableList.builder();
 125         for (DOMStoreWriteTransaction subTx : getSubtransactions()) {
 126             cohortsBuilder.add(subTx.ready());
 127         }
 128         ImmutableList<DOMStoreThreePhaseCommitCohort> cohorts = cohortsBuilder.build();
 129         commitFuture = commitImpl.commit(this, cohorts);
 130
 131         /*
 132          *We remove reference to Commit Implementation in order
 133          *to prevent memory leak
 134          */
 135         commitImpl = null;
 136         return commitFuture;
 137     }
 138
 139     private void checkNotReady() {
 140         checkNotCommited();
 141         checkNotCanceled();
 142     }
 143
 144     private void checkNotCanceled() {
 145         Preconditions.checkState(commitImpl != null, "Transaction was canceled.");
 146     }
 147
 148     private void checkNotCommited() {
 149         checkState(commitFuture == null, "Transaction was already submited.");
 150     }
 151
 152 }