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HDFS-4447. Refactor INodeDirectoryWithSnapshot for supporting general INode diff lists. 

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/HDFS-2802@1440216 13f79535-47bb-0310-9956-ffa450edef68
This commit is contained in:
Tsz-wo Sze 2013-01-29 23:25:49 +00:00
parent 66ea187228
commit 6f4fe09687
12 changed files with 406 additions and 300 deletions
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3
hadoop-hdfs-project/hadoop-hdfs/CHANGES.HDFS-2802.txt
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@ -133,3 +133,6 @@ Branch-2802 Snapshot (Unreleased)
HDFS-4131. Add capability to namenode to get snapshot diff. (Jing Zhao via
suresh)
HDFS-4447. Refactor INodeDirectoryWithSnapshot for support general INode diff
lists. (szetszwo)

15
hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/INode.java
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@ -42,7 +42,6 @@ import org.apache.hadoop.hdfs.server.namenode.snapshot.INodeFileUnderConstructio
import org.apache.hadoop.hdfs.server.namenode.snapshot.INodeFileWithSnapshot;
import org.apache.hadoop.hdfs.server.namenode.snapshot.Snapshot;
import org.apache.hadoop.hdfs.server.namenode.snapshot.diff.Diff;
import org.apache.hadoop.hdfs.util.ReadOnlyList;
import org.apache.hadoop.util.StringUtils;
import com.google.common.annotations.VisibleForTesting;
@ -58,20 +57,6 @@ import com.google.common.primitives.SignedBytes;
public abstract class INode implements Diff.Element<byte[]> {
public static final Log LOG = LogFactory.getLog(INode.class);
static final ReadOnlyList<INode> EMPTY_READ_ONLY_LIST
= ReadOnlyList.Util.emptyList();
/**
* Assert that the snapshot parameter must be null since this class only take
* care current state. Subclasses should override the methods for handling the
* snapshot states.
*/
static void assertNull(Snapshot snapshot) {
if (snapshot != null) {
throw new AssertionError("snapshot is not null: " + snapshot);
}
}
/** A pair of objects. */
public static class Pair<L, R> {
public final L left;

2
hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/INodeDirectory.java
View File

@ -599,7 +599,7 @@ public class INodeDirectory extends INode {
* Note that the returned list is never null.
*/
public ReadOnlyList<INode> getChildrenList(final Snapshot snapshot) {
return children == null ? EMPTY_READ_ONLY_LIST
return children == null ? ReadOnlyList.Util.<INode>emptyList()
: ReadOnlyList.Util.asReadOnlyList(children);
}

117
hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/snapshot/AbstractINodeDiff.java Normal file
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@ -0,0 +1,117 @@
/**
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.hadoop.hdfs.server.namenode.snapshot;
import org.apache.hadoop.hdfs.server.namenode.INode;
import org.apache.hadoop.hdfs.server.namenode.INode.BlocksMapUpdateInfo;
import com.google.common.base.Preconditions;
/**
* The difference of an inode between in two snapshots.
* {@link AbstractINodeDiff2} maintains a list of snapshot diffs,
* <pre>
* d_1 -> d_2 -> ... -> d_n -> null,
* </pre>
* where -> denotes the {@link AbstractINodeDiff#posteriorDiff} reference. The
* current directory state is stored in the field of {@link INode}.
* The snapshot state can be obtained by applying the diffs one-by-one in
* reversed chronological order. Let s_1, s_2, ..., s_n be the corresponding
* snapshots. Then,
* <pre>
* s_n = (current state) - d_n;
* s_{n-1} = s_n - d_{n-1} = (current state) - d_n - d_{n-1};
* ...
* s_k = s_{k+1} - d_k = (current state) - d_n - d_{n-1} - ... - d_k.
* </pre>
*/
abstract class AbstractINodeDiff<N extends INode,
D extends AbstractINodeDiff<N, D>>
implements Comparable<Snapshot> {
/** The snapshot will be obtained after this diff is applied. */
final Snapshot snapshot;
/** The snapshot inode data. It is null when there is no change. */
N snapshotINode;
/**
* Posterior diff is the diff happened after this diff.
* The posterior diff should be first applied to obtain the posterior
* snapshot and then apply this diff in order to obtain this snapshot.
* If the posterior diff is null, the posterior state is the current state.
*/
private D posteriorDiff;
AbstractINodeDiff(Snapshot snapshot, N snapshotINode, D posteriorDiff) {
Preconditions.checkNotNull(snapshot, "snapshot is null");
this.snapshot = snapshot;
this.snapshotINode = snapshotINode;
this.posteriorDiff = posteriorDiff;
}
/** Compare diffs with snapshot ID. */
@Override
public final int compareTo(final Snapshot that) {
return Snapshot.ID_COMPARATOR.compare(this.snapshot, that);
}
/** @return the snapshot object of this diff. */
final Snapshot getSnapshot() {
return snapshot;
}
/** @return the posterior diff. */
final D getPosterior() {
return posteriorDiff;
}
/** @return the posterior diff. */
final void setPosterior(D posterior) {
posteriorDiff = posterior;
}
/** Copy the INode state to the snapshot if it is not done already. */
void checkAndInitINode(N snapshotCopy) {
if (snapshotINode == null) {
if (snapshotCopy == null) {
@SuppressWarnings("unchecked")
final N right = (N)getCurrentINode().createSnapshotCopy().right;
snapshotCopy = right;
}
snapshotINode = snapshotCopy;
}
}
/** @return the current inode. */
abstract N getCurrentINode();
/** @return the inode corresponding to the snapshot. */
N getSnapshotINode() {
// get from this diff, then the posterior diff and then the current inode
for(AbstractINodeDiff<N, D> d = this; ; d = d.posteriorDiff) {
if (d.snapshotINode != null) {
return d.snapshotINode;
} else if (d.posteriorDiff == null) {
return getCurrentINode();
}
}
}
/** Combine the posterior diff and collect blocks for deletion. */
abstract void combinePosteriorAndCollectBlocks(final D posterior,
final BlocksMapUpdateInfo collectedBlocks);
}

150
hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/snapshot/AbstractINodeDiffList.java Normal file
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@ -0,0 +1,150 @@
/**
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.hadoop.hdfs.server.namenode.snapshot;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Iterator;
import java.util.List;
import org.apache.hadoop.hdfs.server.namenode.INode;
import org.apache.hadoop.hdfs.server.namenode.INode.BlocksMapUpdateInfo;
/**
* A list of snapshot diffs for storing snapshot data.
*
* @param <N> The {@link INode} type.
* @param <D> The diff type, which must extend {@link AbstractINodeDiff}.
*/
abstract class AbstractINodeDiffList<N extends INode,
D extends AbstractINodeDiff<N, D>>
implements Iterable<D> {
/** Diff list sorted by snapshot IDs, i.e. in chronological order. */
private final List<D> diffs = new ArrayList<D>();
/** @return this list as a unmodifiable {@link List}. */
final List<D> asList() {
return Collections.unmodifiableList(diffs);
}
/** @return the current inode. */
abstract N getCurrentINode();
/** Add a {@link AbstractINodeDiff} for the given snapshot and inode. */
abstract D addSnapshotDiff(Snapshot snapshot, N inode, boolean isSnapshotCreation);
/**
* Delete the snapshot with the given name. The synchronization of the diff
* list will be done outside.
*
* If the diff to remove is not the first one in the diff list, we need to
* combine the diff with its previous one:
*
* @param snapshot The snapshot to be deleted
* @param collectedBlocks Used to collect information for blocksMap update
* @return The SnapshotDiff containing the deleted snapshot.
* Null if the snapshot with the given name does not exist.
*/
final AbstractINodeDiff<N, D> deleteSnapshotDiff(Snapshot snapshot,
final BlocksMapUpdateInfo collectedBlocks) {
int snapshotIndex = Collections.binarySearch(diffs, snapshot);
if (snapshotIndex < 0) {
return null;
} else {
final D removed = diffs.remove(snapshotIndex);
if (snapshotIndex > 0) {
// combine the to-be-removed diff with its previous diff
final AbstractINodeDiff<N, D> previous = diffs.get(snapshotIndex - 1);
previous.combinePosteriorAndCollectBlocks(removed, collectedBlocks);
previous.setPosterior(removed.getPosterior());
}
removed.setPosterior(null);
return removed;
}
}
/** Append the diff at the end of the list. */
final D append(D diff) {
final AbstractINodeDiff<N, D> last = getLast();
diffs.add(diff);
if (last != null) {
last.setPosterior(diff);
}
return diff;
}
/** Insert the diff to the beginning of the list. */
final void insert(D diff) {
diffs.add(0, diff);
}
/** @return the last diff. */
final D getLast() {
final int n = diffs.size();
return n == 0? null: diffs.get(n - 1);
}
/** @return the last snapshot. */
final Snapshot getLastSnapshot() {
final AbstractINodeDiff<N, D> last = getLast();
return last == null? null: last.getSnapshot();
}
/**
* @return the diff corresponding to the given snapshot.
* When the diff is null, it means that the current state and
* the corresponding snapshot state are the same.
*/
final D getDiff(Snapshot snapshot) {
if (snapshot == null) {
// snapshot == null means the current state, therefore, return null.
return null;
}
final int i = Collections.binarySearch(diffs, snapshot);
if (i >= 0) {
// exact match
return diffs.get(i);
} else {
// Exact match not found means that there were no changes between
// given snapshot and the next state so that the diff for the given
// snapshot was not recorded. Thus, return the next state.
final int j = -i - 1;
return j < diffs.size()? diffs.get(j): null;
}
}
/**
* Check if the latest snapshot diff exists. If not, add it.
* @return the latest snapshot diff, which is never null.
*/
final D checkAndAddLatestSnapshotDiff(Snapshot latest) {
final D last = getLast();
return last != null && last.snapshot.equals(latest)? last
: addSnapshotDiff(latest, getCurrentINode(), false);
}
@Override
public Iterator<D> iterator() {
return diffs.iterator();
}
@Override
public String toString() {
return "diffs=" + diffs;
}
}

20
hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/snapshot/INodeDirectorySnapshottable.java
View File

@ -150,7 +150,7 @@ public class INodeDirectorySnapshottable extends INodeDirectoryWithSnapshot {
public INodeDirectorySnapshottable(INodeDirectory dir) {
super(dir, true, dir instanceof INodeDirectoryWithSnapshot ?
((INodeDirectoryWithSnapshot) dir).getSnapshotDiffs() : null);
((INodeDirectoryWithSnapshot) dir).getDiffs(): null);
}
/** @return the number of existing snapshots. */
@ -252,7 +252,7 @@ public class INodeDirectorySnapshottable extends INodeDirectoryWithSnapshot {
+ "snapshot with the same name \"" + name + "\".");
}
addSnapshotDiff(s, this, true);
getDiffs().addSnapshotDiff(s, this, true);
snapshotsByNames.add(-i - 1, s);
//set modification time
@ -264,7 +264,7 @@ public class INodeDirectorySnapshottable extends INodeDirectoryWithSnapshot {
/**
* Remove the snapshot with the given name from {@link #snapshotsByNames},
* and delete all the corresponding SnapshotDiff.
* and delete all the corresponding DirectoryDiff.
*
* @param snapshotName The name of the snapshot to be removed
* @param collectedBlocks Used to collect information to update blocksMap
@ -286,14 +286,14 @@ public class INodeDirectorySnapshottable extends INodeDirectoryWithSnapshot {
}
/**
* Recursively delete SnapshotDiff associated with the given snapshot under a
* Recursively delete DirectoryDiff associated with the given snapshot under a
* directory
*/
private void deleteDiffsForSnapshot(Snapshot snapshot, INodeDirectory dir,
BlocksMapUpdateInfo collectedBlocks) {
if (dir instanceof INodeDirectoryWithSnapshot) {
INodeDirectoryWithSnapshot sdir = (INodeDirectoryWithSnapshot) dir;
sdir.deleteSnapshotDiff(snapshot, collectedBlocks);
sdir.getDiffs().deleteSnapshotDiff(snapshot, collectedBlocks);
}
ReadOnlyList<INode> children = dir.getChildrenList(null);
for (INode child : children) {
@ -401,7 +401,7 @@ public class INodeDirectorySnapshottable extends INodeDirectoryWithSnapshot {
out.println();
out.print(prefix);
int n = 0;
for(SnapshotDiff diff : getSnapshotDiffs()) {
for(DirectoryDiff diff : getDiffs()) {
if (diff.isSnapshotRoot()) {
n++;
}
@ -415,12 +415,12 @@ public class INodeDirectorySnapshottable extends INodeDirectoryWithSnapshot {
@Override
public Iterator<Pair<? extends INode, Snapshot>> iterator() {
return new Iterator<Pair<? extends INode, Snapshot>>() {
final Iterator<SnapshotDiff> i = getSnapshotDiffs().iterator();
private SnapshotDiff next = findNext();
final Iterator<DirectoryDiff> i = getDiffs().iterator();
private DirectoryDiff next = findNext();
private SnapshotDiff findNext() {
private DirectoryDiff findNext() {
for(; i.hasNext(); ) {
final SnapshotDiff diff = i.next();
final DirectoryDiff diff = i.next();
if (diff.isSnapshotRoot()) {
return diff;
}

301
hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/snapshot/INodeDirectoryWithSnapshot.java
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@ -50,7 +50,7 @@ public class INodeDirectoryWithSnapshot extends INodeDirectoryWithQuota {
* The difference between the current state and a previous snapshot
* of the children list of an INodeDirectory.
*/
public static class ChildrenDiff extends Diff<byte[], INode> {
static class ChildrenDiff extends Diff<byte[], INode> {
ChildrenDiff() {}
private ChildrenDiff(final List<INode> created, final List<INode> deleted) {
@ -173,100 +173,56 @@ public class INodeDirectoryWithSnapshot extends INodeDirectoryWithQuota {
}
/**
* The difference between two snapshots. {@link INodeDirectoryWithSnapshot}
* maintains a list of snapshot diffs,
* <pre>
* d_1 -> d_2 -> ... -> d_n -> null,
* </pre>
* where -> denotes the {@link SnapshotDiff#posteriorDiff} reference. The
* current directory state is stored in the field of {@link INodeDirectory}.
* The snapshot state can be obtained by applying the diffs one-by-one in
* reversed chronological order. Let s_1, s_2, ..., s_n be the corresponding
* snapshots. Then,
* <pre>
* s_n = (current state) - d_n;
* s_{n-1} = s_n - d_{n-1} = (current state) - d_n - d_{n-1};
* ...
* s_k = s_{k+1} - d_k = (current state) - d_n - d_{n-1} - ... - d_k.
* </pre>
* The difference of an {@link INodeDirectory} between two snapshots.
*/
public class SnapshotDiff implements Comparable<Snapshot> {
/** The snapshot will be obtained after this diff is applied. */
final Snapshot snapshot;
class DirectoryDiff extends AbstractINodeDiff<INodeDirectory, DirectoryDiff> {
/** The size of the children list at snapshot creation time. */
final int childrenSize;
/**
* Posterior diff is the diff happened after this diff.
* The posterior diff should be first applied to obtain the posterior
* snapshot and then apply this diff in order to obtain this snapshot.
* If the posterior diff is null, the posterior state is the current state.
*/
private SnapshotDiff posteriorDiff;
private final int childrenSize;
/** The children list diff. */
private final ChildrenDiff diff;
/** The snapshot inode data. It is null when there is no change. */
private INodeDirectory snapshotINode = null;
private SnapshotDiff(Snapshot snapshot, INodeDirectory dir) {
Preconditions.checkNotNull(snapshot, "snapshot is null");
private DirectoryDiff(Snapshot snapshot, INodeDirectory dir) {
super(snapshot, null, null);
this.snapshot = snapshot;
this.childrenSize = dir.getChildrenList(null).size();
this.diff = new ChildrenDiff();
}
/** Constructor used by FSImage loading */
SnapshotDiff(Snapshot snapshot,
int childrenSize, INodeDirectory snapshotINode,
SnapshotDiff posteriorDiff, List<INode> createdList,
List<INode> deletedList) {
this.snapshot = snapshot;
DirectoryDiff(Snapshot snapshot, INodeDirectory snapshotINode,
DirectoryDiff posteriorDiff, int childrenSize,
List<INode> createdList, List<INode> deletedList) {
super(snapshot, snapshotINode, posteriorDiff);
this.childrenSize = childrenSize;
this.snapshotINode = snapshotINode;
this.posteriorDiff = posteriorDiff;
this.diff = new ChildrenDiff(createdList, deletedList);
}
ChildrenDiff getDiff() {
ChildrenDiff getChildrenDiff() {
return diff;
}
/** Compare diffs with snapshot ID. */
@Override
public int compareTo(final Snapshot that) {
return Snapshot.ID_COMPARATOR.compare(this.snapshot, that);
}
/** Is the inode the root of the snapshot? */
boolean isSnapshotRoot() {
return snapshotINode == snapshot.getRoot();
}
/** Copy the INode state to the snapshot if it is not done already. */
private void checkAndInitINode(INodeDirectory snapshotCopy) {
if (snapshotINode == null) {
if (snapshotCopy == null) {
snapshotCopy = new INodeDirectory(INodeDirectoryWithSnapshot.this,
false);
}
snapshotINode = snapshotCopy;
}
@Override
INodeDirectory getCurrentINode() {
return INodeDirectoryWithSnapshot.this;
}
/** @return the snapshot object of this diff. */
Snapshot getSnapshot() {
return snapshot;
}
private INodeDirectory getSnapshotINode() {
// get from this diff, then the posterior diff and then the current inode
for(SnapshotDiff d = this; ; d = d.posteriorDiff) {
if (d.snapshotINode != null) {
return d.snapshotINode;
} else if (d.posteriorDiff == null) {
return INodeDirectoryWithSnapshot.this;
@Override
void combinePosteriorAndCollectBlocks(final DirectoryDiff posterior,
final BlocksMapUpdateInfo collectedBlocks) {
diff.combinePosterior(posterior.diff, new Diff.Processor<INode>() {
/** Collect blocks for deleted files. */
@Override
public void process(INode inode) {
if (inode != null && inode instanceof INodeFile) {
((INodeFile)inode).collectSubtreeBlocksAndClear(collectedBlocks);
}
}
}
});
}
/**
@ -281,11 +237,11 @@ public class INodeDirectoryWithSnapshot extends INodeDirectoryWithQuota {
private List<INode> initChildren() {
if (children == null) {
final ChildrenDiff combined = new ChildrenDiff();
for(SnapshotDiff d = SnapshotDiff.this; d != null; d = d.posteriorDiff) {
for(DirectoryDiff d = DirectoryDiff.this; d != null; d = d.getPosterior()) {
combined.combinePosterior(d.diff, null);
}
children = combined.apply2Current(ReadOnlyList.Util.asList(
INodeDirectoryWithSnapshot.this.getChildrenList(null)));
getCurrentINode().getChildrenList(null)));
}
return children;
}
@ -314,7 +270,7 @@ public class INodeDirectoryWithSnapshot extends INodeDirectoryWithQuota {
/** @return the child with the given name. */
INode getChild(byte[] name, boolean checkPosterior) {
for(SnapshotDiff d = this; ; d = d.posteriorDiff) {
for(DirectoryDiff d = this; ; d = d.getPosterior()) {
final Container<INode> returned = d.diff.accessPrevious(name);
if (returned != null) {
// the diff is able to determine the inode
@ -322,17 +278,18 @@ public class INodeDirectoryWithSnapshot extends INodeDirectoryWithQuota {
} else if (!checkPosterior) {
// Since checkPosterior is false, return null, i.e. not found.
return null;
} else if (d.posteriorDiff == null) {
} else if (d.getPosterior() == null) {
// no more posterior diff, get from current inode.
return INodeDirectoryWithSnapshot.this.getChild(name, null);
return getCurrentINode().getChild(name, null);
}
}
}
@Override
public String toString() {
final DirectoryDiff posterior = getPosterior();
return "\n " + snapshot + " (-> "
+ (posteriorDiff == null? null: posteriorDiff.snapshot)
+ (posterior == null? null: posterior.snapshot)
+ ") childrenSize=" + childrenSize + ", " + diff;
}
@ -361,9 +318,24 @@ public class INodeDirectoryWithSnapshot extends INodeDirectoryWithQuota {
// Write diff. Node need to write poseriorDiff, since diffs is a list.
diff.write(out);
}
private List<INodeDirectory> getSnapshotDirectory() {
return diff.getDirsInDeleted();
}
/** A list of directory diffs. */
class DirectoryDiffList extends AbstractINodeDiffList<INodeDirectory, DirectoryDiff> {
@Override
INodeDirectoryWithSnapshot getCurrentINode() {
return INodeDirectoryWithSnapshot.this;
}
@Override
DirectoryDiff addSnapshotDiff(Snapshot snapshot, INodeDirectory dir,
boolean isSnapshotCreation) {
final DirectoryDiff d = new DirectoryDiff(snapshot, dir);
if (isSnapshotCreation) {
//for snapshot creation, snapshotINode is the same as the snapshot root
d.snapshotINode = snapshot.getRoot();
}
return append(d);
}
}
@ -374,7 +346,7 @@ public class INodeDirectoryWithSnapshot extends INodeDirectoryWithQuota {
= new INodeDirectoryWithSnapshot(dir, true, null);
if (latest != null) {
// add a diff for the latest snapshot
withSnapshot.addSnapshotDiff(latest, dir, false);
withSnapshot.diffs.addSnapshotDiff(latest, dir, false);
}
return withSnapshot;
}
@ -402,15 +374,17 @@ public class INodeDirectoryWithSnapshot extends INodeDirectoryWithQuota {
laterSnapshot = fromSnapshot;
}
int earlierDiffIndex = Collections.binarySearch(diffs, earlierSnapshot);
if (earlierDiffIndex < 0 && (-earlierDiffIndex - 1) == diffs.size()) {
final List<DirectoryDiff> difflist = diffs.asList();
final int size = difflist.size();
int earlierDiffIndex = Collections.binarySearch(difflist, earlierSnapshot);
if (earlierDiffIndex < 0 && (-earlierDiffIndex - 1) == size) {
// if the earlierSnapshot is after the latest SnapshotDiff stored in diffs,
// no modification happened after the earlierSnapshot
return false;
}
int laterDiffIndex = diffs.size();
int laterDiffIndex = size;
if (laterSnapshot != null) {
laterDiffIndex = Collections.binarySearch(diffs, laterSnapshot);
laterDiffIndex = Collections.binarySearch(difflist, laterSnapshot);
if (laterDiffIndex == -1 || laterDiffIndex == 0) {
// if the endSnapshot is the earliest SnapshotDiff stored in
// diffs, or before it, no modification happened before the endSnapshot
@ -425,7 +399,7 @@ public class INodeDirectoryWithSnapshot extends INodeDirectoryWithQuota {
boolean dirMetadataChanged = false;
INodeDirectory dirCopy = null;
for (int i = earlierDiffIndex; i < laterDiffIndex; i++) {
SnapshotDiff sdiff = diffs.get(i);
DirectoryDiff sdiff = difflist.get(i);
diff.combinePosterior(sdiff.diff, null);
if (dirMetadataChanged == false && sdiff.snapshotINode != null) {
if (dirCopy == null) {
@ -441,9 +415,8 @@ public class INodeDirectoryWithSnapshot extends INodeDirectoryWithQuota {
if (!diff.isEmpty() || dirMetadataChanged) {
return true;
} else if (dirCopy != null) {
for (int i = laterDiffIndex; i < diffs.size(); i++) {
if (diffs.get(i).snapshotINode != null
&& !dirCopy.metadataEquals(diffs.get(i).snapshotINode)) {
for (int i = laterDiffIndex; i < size; i++) {
if (!dirCopy.metadataEquals(difflist.get(i).snapshotINode)) {
return true;
}
}
@ -453,134 +426,28 @@ public class INodeDirectoryWithSnapshot extends INodeDirectoryWithQuota {
}
/** Diff list sorted by snapshot IDs, i.e. in chronological order. */
private final List<SnapshotDiff> diffs;
private final DirectoryDiffList diffs;
INodeDirectoryWithSnapshot(INodeDirectory that, boolean adopt,
List<SnapshotDiff> diffs) {
DirectoryDiffList diffs) {
super(that, adopt, that.getNsQuota(), that.getDsQuota());
this.diffs = diffs != null? diffs: new ArrayList<SnapshotDiff>();
}
/**
* Delete the snapshot with the given name. The synchronization of the diff
* list will be done outside.
*
* If the diff to remove is not the first one in the diff list, we need to
* combine the diff with its previous one:
*
* @param snapshot The snapshot to be deleted
* @param collectedBlocks Used to collect information for blocksMap update
* @return The SnapshotDiff containing the deleted snapshot.
* Null if the snapshot with the given name does not exist.
*/
SnapshotDiff deleteSnapshotDiff(Snapshot snapshot,
final BlocksMapUpdateInfo collectedBlocks) {
int snapshotIndex = Collections.binarySearch(diffs, snapshot);
if (snapshotIndex == -1) {
return null;
} else {
SnapshotDiff diffToRemove = null;
diffToRemove = diffs.remove(snapshotIndex);
if (snapshotIndex > 0) {
// combine the to-be-removed diff with its previous diff
SnapshotDiff previousDiff = diffs.get(snapshotIndex - 1);
previousDiff.diff.combinePosterior(diffToRemove.diff,
new Diff.Processor<INode>() {
/** Collect blocks for deleted files. */
@Override
public void process(INode inode) {
if (inode != null && inode instanceof INodeFile) {
((INodeFile)inode).collectSubtreeBlocksAndClear(collectedBlocks);
}
}
});
previousDiff.posteriorDiff = diffToRemove.posteriorDiff;
diffToRemove.posteriorDiff = null;
}
return diffToRemove;
}
}
/** Insert a SnapshotDiff to the head of diffs */
public void insertDiff(SnapshotDiff diff) {
diffs.add(0, diff);
}
/** Add a {@link SnapshotDiff} for the given snapshot and directory. */
SnapshotDiff addSnapshotDiff(Snapshot snapshot, INodeDirectory dir,
boolean isSnapshotCreation) {
final SnapshotDiff last = getLastSnapshotDiff();
final SnapshotDiff d = new SnapshotDiff(snapshot, dir);
if (isSnapshotCreation) {
//for snapshot creation, snapshotINode is the same as the snapshot root
d.snapshotINode = snapshot.getRoot();
}
diffs.add(d);
if (last != null) {
last.posteriorDiff = d;
}
return d;
}
SnapshotDiff getLastSnapshotDiff() {
final int n = diffs.size();
return n == 0? null: diffs.get(n - 1);
this.diffs = diffs != null? diffs: new DirectoryDiffList();
}
/** @return the last snapshot. */
public Snapshot getLastSnapshot() {
final SnapshotDiff last = getLastSnapshotDiff();
return last == null? null: last.getSnapshot();
return diffs.getLastSnapshot();
}
/**
* Check if the latest snapshot diff exists. If not, add it.
* @return the latest snapshot diff, which is never null.
*/
private SnapshotDiff checkAndAddLatestSnapshotDiff(Snapshot latest) {
final SnapshotDiff last = getLastSnapshotDiff();
return last != null && last.snapshot.equals(latest)? last
: addSnapshotDiff(latest, this, false);
}
/**
* Check if the latest {@link ChildrenDiff} exists. If not, add it.
* @return the latest {@link ChildrenDiff}, which is never null.
*/
ChildrenDiff checkAndAddLatestDiff(Snapshot latest) {
return checkAndAddLatestSnapshotDiff(latest).diff;
}
/**
* @return {@link #snapshots}
*/
List<SnapshotDiff> getSnapshotDiffs() {
/** @return the snapshot diff list. */
DirectoryDiffList getDiffs() {
return diffs;
}
/**
* @return the diff corresponding to the given snapshot.
* When the diff is null, it means that the current state and
* the corresponding snapshot state are the same.
*/
SnapshotDiff getSnapshotDiff(Snapshot snapshot) {
if (snapshot == null) {
// snapshot == null means the current state, therefore, return null.
return null;
}
final int i = Collections.binarySearch(diffs, snapshot);
if (i >= 0) {
// exact match
return diffs.get(i);
} else {
// Exact match not found means that there were no changes between
// given snapshot and the next state so that the diff for the given
// snapshot was not recorded. Thus, return the next state.
final int j = -i - 1;
return j < diffs.size()? diffs.get(j): null;
}
@Override
public Pair<INodeDirectoryWithSnapshot, INodeDirectory> createSnapshotCopy() {
return new Pair<INodeDirectoryWithSnapshot, INodeDirectory>(this,
new INodeDirectory(this, false));
}
@Override
@ -592,7 +459,7 @@ public class INodeDirectoryWithSnapshot extends INodeDirectoryWithQuota {
/** Save the snapshot copy to the latest snapshot. */
public void saveSelf2Snapshot(Snapshot latest, INodeDirectory snapshotCopy) {
if (latest != null) {
checkAndAddLatestSnapshotDiff(latest).checkAndInitINode(snapshotCopy);
diffs.checkAndAddLatestSnapshotDiff(latest).checkAndInitINode(snapshotCopy);
}
}
@ -604,7 +471,7 @@ public class INodeDirectoryWithSnapshot extends INodeDirectoryWithQuota {
return child;
}
final SnapshotDiff diff = checkAndAddLatestSnapshotDiff(latest);
final DirectoryDiff diff = diffs.checkAndAddLatestSnapshotDiff(latest);
if (diff.getChild(child.getLocalNameBytes(), false) != null) {
// it was already saved in the latest snapshot earlier.
return child;
@ -629,7 +496,7 @@ public class INodeDirectoryWithSnapshot extends INodeDirectoryWithQuota {
ChildrenDiff diff = null;
Integer undoInfo = null;
if (latest != null) {
diff = checkAndAddLatestDiff(latest);
diff = diffs.checkAndAddLatestSnapshotDiff(latest).diff;
undoInfo = diff.create(inode);
}
final boolean added = super.addChild(inode, setModTime, null);
@ -644,7 +511,7 @@ public class INodeDirectoryWithSnapshot extends INodeDirectoryWithQuota {
ChildrenDiff diff = null;
UndoInfo<INode> undoInfo = null;
if (latest != null) {
diff = checkAndAddLatestDiff(latest);
diff = diffs.checkAndAddLatestSnapshotDiff(latest).diff;
undoInfo = diff.delete(child);
}
final INode removed = super.removeChild(child, null);
@ -665,54 +532,54 @@ public class INodeDirectoryWithSnapshot extends INodeDirectoryWithQuota {
@Override
public ReadOnlyList<INode> getChildrenList(Snapshot snapshot) {
final SnapshotDiff diff = getSnapshotDiff(snapshot);
final DirectoryDiff diff = diffs.getDiff(snapshot);
return diff != null? diff.getChildrenList(): super.getChildrenList(null);
}
@Override
public INode getChild(byte[] name, Snapshot snapshot) {
final SnapshotDiff diff = getSnapshotDiff(snapshot);
final DirectoryDiff diff = diffs.getDiff(snapshot);
return diff != null? diff.getChild(name, true): super.getChild(name, null);
}
@Override
public String getUserName(Snapshot snapshot) {
final SnapshotDiff diff = getSnapshotDiff(snapshot);
final DirectoryDiff diff = diffs.getDiff(snapshot);
return diff != null? diff.getSnapshotINode().getUserName()
: super.getUserName(null);
}
@Override
public String getGroupName(Snapshot snapshot) {
final SnapshotDiff diff = getSnapshotDiff(snapshot);
final DirectoryDiff diff = diffs.getDiff(snapshot);
return diff != null? diff.getSnapshotINode().getGroupName()
: super.getGroupName(null);
}
@Override
public FsPermission getFsPermission(Snapshot snapshot) {
final SnapshotDiff diff = getSnapshotDiff(snapshot);
final DirectoryDiff diff = diffs.getDiff(snapshot);
return diff != null? diff.getSnapshotINode().getFsPermission()
: super.getFsPermission(null);
}
@Override
public long getAccessTime(Snapshot snapshot) {
final SnapshotDiff diff = getSnapshotDiff(snapshot);
final DirectoryDiff diff = diffs.getDiff(snapshot);
return diff != null? diff.getSnapshotINode().getAccessTime()
: super.getAccessTime(null);
}
@Override
public long getModificationTime(Snapshot snapshot) {
final SnapshotDiff diff = getSnapshotDiff(snapshot);
final DirectoryDiff diff = diffs.getDiff(snapshot);
return diff != null? diff.getSnapshotINode().getModificationTime()
: super.getModificationTime(null);
}
@Override
public String toString() {
return super.toString() + ", diffs=" + getSnapshotDiffs();
return super.toString() + ", " + diffs;
}
/**
@ -726,8 +593,8 @@ public class INodeDirectoryWithSnapshot extends INodeDirectoryWithQuota {
public int getSnapshotDirectory(
Map<Snapshot, List<INodeDirectory>> snapshotDirMap) {
int dirNum = 0;
for (SnapshotDiff sdiff : diffs) {
List<INodeDirectory> list = sdiff.getSnapshotDirectory();
for (DirectoryDiff sdiff : diffs) {
List<INodeDirectory> list = sdiff.getChildrenDiff().getDirsInDeleted();
if (list.size() > 0) {
snapshotDirMap.put(sdiff.snapshot, list);
dirNum += list.size();

23
hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/snapshot/SnapshotFSImageFormat.java
View File

@ -33,7 +33,7 @@ import org.apache.hadoop.hdfs.server.namenode.INode;
import org.apache.hadoop.hdfs.server.namenode.INodeDirectory;
import org.apache.hadoop.hdfs.server.namenode.INodeFile;
import org.apache.hadoop.hdfs.server.namenode.snapshot.INodeDirectoryWithSnapshot.ChildrenDiff;
import org.apache.hadoop.hdfs.server.namenode.snapshot.INodeDirectoryWithSnapshot.SnapshotDiff;
import org.apache.hadoop.hdfs.server.namenode.snapshot.INodeDirectoryWithSnapshot.DirectoryDiff;
import org.apache.hadoop.hdfs.server.namenode.snapshot.Snapshot.Root;
import org.apache.hadoop.hdfs.util.ReadOnlyList;
@ -70,13 +70,13 @@ public class SnapshotFSImageFormat {
public static void saveSnapshotDiffs(INodeDirectoryWithSnapshot sNode,
DataOutputStream out) throws IOException {
// # of SnapshotDiff
List<SnapshotDiff> diffs = sNode.getSnapshotDiffs();
List<DirectoryDiff> diffs = sNode.getDiffs().asList();
// Record the SnapshotDiff in reversed order, so that we can find the
// correct reference for INodes in the created list when loading the
// FSImage
out.writeInt(diffs.size());
for (int i = diffs.size() - 1; i >= 0; i--) {
SnapshotDiff sdiff = diffs.get(i);
DirectoryDiff sdiff = diffs.get(i);
sdiff.write(out);
}
}
@ -91,8 +91,8 @@ public class SnapshotFSImageFormat {
INodeDirectoryWithSnapshot parent) throws IOException {
// the INode in the created list should be a reference to another INode
// in posterior SnapshotDiffs or one of the current children
for (SnapshotDiff postDiff : parent.getSnapshotDiffs()) {
INode created = findCreated(createdNodeName, postDiff.getDiff());
for (DirectoryDiff postDiff : parent.getDiffs()) {
INode created = findCreated(createdNodeName, postDiff.getChildrenDiff());
if (created != null) {
return created;
} // else go to the next SnapshotDiff
@ -266,8 +266,8 @@ public class SnapshotFSImageFormat {
DataInputStream in, FSImageFormat.Loader loader)
throws IOException {
for (int i = 0; i < numSnapshotDiffs; i++) {
SnapshotDiff diff = loadSnapshotDiff(parentWithSnapshot, in, loader);
parentWithSnapshot.insertDiff(diff);
DirectoryDiff diff = loadSnapshotDiff(parentWithSnapshot, in, loader);
parentWithSnapshot.getDiffs().insert(diff);
}
}
@ -321,7 +321,7 @@ public class SnapshotFSImageFormat {
* using.
* @return A {@link SnapshotDiff}.
*/
private static SnapshotDiff loadSnapshotDiff(
private static DirectoryDiff loadSnapshotDiff(
INodeDirectoryWithSnapshot parent, DataInputStream in,
FSImageFormat.Loader loader) throws IOException {
// 1. Load SnapshotDiff#childrenSize
@ -342,9 +342,10 @@ public class SnapshotFSImageFormat {
List<INode> deletedList = loadDeletedList(parent, createdList, in, loader);
// 6. Compose the SnapshotDiff
SnapshotDiff sdiff = parent.new SnapshotDiff(snapshot, childrenSize,
snapshotINode, parent.getSnapshotDiffs().isEmpty() ? null : parent
.getSnapshotDiffs().get(0), createdList, deletedList);
List<DirectoryDiff> diffs = parent.getDiffs().asList();
DirectoryDiff sdiff = parent.new DirectoryDiff(snapshot, snapshotINode,
diffs.isEmpty() ? null : diffs.get(0),
childrenSize, createdList, deletedList);
return sdiff;
}

17
hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/snapshot/diff/Diff.java
View File

@ -451,23 +451,10 @@ public class Diff<K, E extends Diff.Element<K>> {
}
}
/** Convert the element list to a compact string. */
static <E> String toString(List<E> elements) {
if (elements == null || elements.isEmpty()) {
return "<empty>";
}
final StringBuilder b = new StringBuilder("[")
.append(elements.get(0));
for(int i = 1; i < elements.size(); i++) {
b.append(", ").append(elements.get(i));
}
return b.append("]").toString();
}
@Override
public String toString() {
return getClass().getSimpleName()
+ "{created=" + toString(created)
+ ", deleted=" + toString(deleted) + "}";
+ "{created=" + getCreatedList()
+ ", deleted=" + getDeletedList() + "}";
}
}

12
hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/namenode/snapshot/TestINodeFileUnderConstructionWithSnapshot.java
View File

@ -108,7 +108,7 @@ public class TestINodeFileUnderConstructionWithSnapshot {
INodeFile fileNode = (INodeFile) fsdir.getINode(file.toString());
INodeDirectorySnapshottable dirNode = (INodeDirectorySnapshottable) fsdir
.getINode(dir.toString());
ChildrenDiff diff = dirNode.getLastSnapshotDiff().getDiff();
ChildrenDiff diff = dirNode.getDiffs().getLast().getChildrenDiff();
INode nodeInCreated = diff.searchCreated(fileNode.getLocalNameBytes());
assertTrue(fileNode == nodeInCreated);
INode nodeInDeleted = diff.searchDeleted(fileNode.getLocalNameBytes());
@ -120,7 +120,7 @@ public class TestINodeFileUnderConstructionWithSnapshot {
DFSTestUtil.appendFile(hdfs, file, BLOCKSIZE);
// check the circular list and corresponding inodes
diff = dirNode.getLastSnapshotDiff().getDiff();
diff = dirNode.getDiffs().getLast().getChildrenDiff();
fileNode = (INodeFile) fsdir.getINode(file.toString());
nodeInCreated = diff.searchCreated(fileNode.getLocalNameBytes());
assertTrue(fileNode == nodeInCreated);
@ -140,7 +140,7 @@ public class TestINodeFileUnderConstructionWithSnapshot {
DFSTestUtil.appendFile(hdfs, file, BLOCKSIZE);
// check the circular list and corresponding inodes
diff = dirNode.getLastSnapshotDiff().getDiff();
diff = dirNode.getDiffs().getLast().getChildrenDiff();
fileNode = (INodeFile) fsdir.getINode(file.toString());
nodeInCreated = diff.searchCreated(fileNode.getLocalNameBytes());
assertTrue(fileNode == nodeInCreated);
@ -187,7 +187,7 @@ public class TestINodeFileUnderConstructionWithSnapshot {
assertEquals(BLOCKSIZE * 2, ((INodeFile) fileNode).computeFileSize(true));
INodeDirectorySnapshottable dirNode = (INodeDirectorySnapshottable) fsdir
.getINode(dir.toString());
ChildrenDiff diff = dirNode.getLastSnapshotDiff().getDiff();
ChildrenDiff diff = dirNode.getDiffs().getLast().getChildrenDiff();
INode nodeInDeleted_S0 = diff.searchDeleted(fileNode.getLocalNameBytes());
assertTrue(nodeInDeleted_S0 instanceof INodeFileUnderConstructionSnapshot);
assertEquals(BLOCKSIZE * 2,
@ -199,7 +199,7 @@ public class TestINodeFileUnderConstructionWithSnapshot {
// re-check nodeInDeleted_S0
dirNode = (INodeDirectorySnapshottable) fsdir.getINode(dir.toString());
diff = dirNode.getLastSnapshotDiff().getDiff();
diff = dirNode.getDiffs().getLast().getChildrenDiff();
nodeInDeleted_S0 = diff.searchDeleted(fileNode.getLocalNameBytes());
assertTrue(nodeInDeleted_S0 instanceof INodeFileUnderConstructionSnapshot);
assertEquals(BLOCKSIZE * 2,
@ -213,7 +213,7 @@ public class TestINodeFileUnderConstructionWithSnapshot {
// have been stored in s1's deleted list
fileNode = (INodeFile) fsdir.getINode(file.toString());
dirNode = (INodeDirectorySnapshottable) fsdir.getINode(dir.toString());
diff = dirNode.getLastSnapshotDiff().getDiff();
diff = dirNode.getDiffs().getLast().getChildrenDiff();
INode nodeInCreated_S1 = diff.searchCreated(fileNode.getLocalNameBytes());
assertTrue(fileNode == nodeInCreated_S1);
assertTrue(fileNode instanceof INodeFileWithSnapshot);

4
hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/namenode/snapshot/TestSnapshotRename.java
View File

@ -31,7 +31,7 @@ import org.apache.hadoop.hdfs.DistributedFileSystem;
import org.apache.hadoop.hdfs.MiniDFSCluster;
import org.apache.hadoop.hdfs.server.namenode.FSDirectory;
import org.apache.hadoop.hdfs.server.namenode.FSNamesystem;
import org.apache.hadoop.hdfs.server.namenode.snapshot.INodeDirectoryWithSnapshot.SnapshotDiff;
import org.apache.hadoop.hdfs.server.namenode.snapshot.INodeDirectoryWithSnapshot.DirectoryDiff;
import org.apache.hadoop.hdfs.util.ReadOnlyList;
import org.apache.hadoop.ipc.RemoteException;
import org.junit.After;
@ -91,7 +91,7 @@ public class TestSnapshotRename {
for (int i = 0; i < listByName.size(); i++) {
assertEquals(sortedNames[i], listByName.get(i).getRoot().getLocalName());
}
List<SnapshotDiff> listByTime = srcRoot.getSnapshotDiffs();
List<DirectoryDiff> listByTime = srcRoot.getDiffs().asList();
assertEquals(names.length, listByTime.size());
for (int i = 0; i < listByTime.size(); i++) {
assertEquals(names[i], listByTime.get(i).getSnapshot().getRoot().getLocalName());

42
hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/namenode/snapshot/diff/TestDiff.java
View File

@ -124,10 +124,10 @@ public class TestDiff {
c = diffs.get(i).apply2Previous(c);
}
if (!hasIdenticalElements(current, c)) {
System.out.println("previous = " + Diff.toString(previous));
System.out.println("previous = " + previous);
System.out.println();
System.out.println("current = " + Diff.toString(current));
System.out.println("c = " + Diff.toString(c));
System.out.println("current = " + current);
System.out.println("c = " + c);
throw new AssertionError("current and c are not identical.");
}
@ -137,10 +137,10 @@ public class TestDiff {
p = diffs.get(i).apply2Current(p);
}
if (!hasIdenticalElements(previous, p)) {
System.out.println("previous = " + Diff.toString(previous));
System.out.println("p = " + Diff.toString(p));
System.out.println("previous = " + previous);
System.out.println("p = " + p);
System.out.println();
System.out.println("current = " + Diff.toString(current));
System.out.println("current = " + current);
throw new AssertionError("previous and p are not identical.");
}
}
@ -155,20 +155,20 @@ public class TestDiff {
// check if current == previous + combined
final List<INode> c = combined.apply2Previous(previous);
if (!hasIdenticalElements(current, c)) {
System.out.println("previous = " + Diff.toString(previous));
System.out.println("previous = " + previous);
System.out.println();
System.out.println("current = " + Diff.toString(current));
System.out.println("c = " + Diff.toString(c));
System.out.println("current = " + current);
System.out.println("c = " + c);
throw new AssertionError("current and c are not identical.");
}
// check if previous == current - combined
final List<INode> p = combined.apply2Current(current);
if (!hasIdenticalElements(previous, p)) {
System.out.println("previous = " + Diff.toString(previous));
System.out.println("p = " + Diff.toString(p));
System.out.println("previous = " + previous);
System.out.println("p = " + p);
System.out.println();
System.out.println("current = " + Diff.toString(current));
System.out.println("current = " + current);
throw new AssertionError("previous and p are not identical.");
}
}
@ -228,10 +228,6 @@ public class TestDiff {
return true;
}
static String toString(Diff<byte[], INode> diff) {
return diff.toString();
}
static String toString(INode inode) {
return inode == null? null
: inode.getLocalName() + ":" + inode.getModificationTime();
@ -256,13 +252,13 @@ public class TestDiff {
final boolean testUndo = RANDOM.nextInt(UNDO_TEST_P) == 0;
String before = null;
if (testUndo) {
before = toString(diff);
before = diff.toString();
}
final int undoInfo = diff.create(inode);
if (testUndo) {
final String after = toString(diff);
final String after = diff.toString();
//undo
diff.undoCreate(inode, undoInfo);
assertDiff(before, diff);
@ -281,13 +277,13 @@ public class TestDiff {
final boolean testUndo = RANDOM.nextInt(UNDO_TEST_P) == 0;
String before = null;
if (testUndo) {
before = toString(diff);
before = diff.toString();
}
final UndoInfo<INode> undoInfo = diff.delete(inode);
if (testUndo) {
final String after = toString(diff);
final String after = diff.toString();
//undo
diff.undoDelete(inode, undoInfo);
assertDiff(before, diff);
@ -311,13 +307,13 @@ public class TestDiff {
final boolean testUndo = RANDOM.nextInt(UNDO_TEST_P) == 0;
String before = null;
if (testUndo) {
before = toString(diff);
before = diff.toString();
}
final UndoInfo<INode> undoInfo = diff.modify(oldinode, newinode);
if (testUndo) {
final String after = toString(diff);
final String after = diff.toString();
//undo
diff.undoModify(oldinode, newinode, undoInfo);
assertDiff(before, diff);
@ -329,6 +325,6 @@ public class TestDiff {
}
static void assertDiff(String s, Diff<byte[], INode> diff) {
Assert.assertEquals(s, toString(diff));
Assert.assertEquals(s, diff.toString());
}
}