Author: thomasm
Date: Thu Aug 9 13:18:57 2012
New Revision: 1371198
URL: http://svn.apache.org/viewvc?rev=1371198&view=rev
Log:
OAK-45 Add support for branching and merging - wrapper to simplify testing with
MicroKernel implementations that don't support branch and merge
Added:
jackrabbit/oak/trunk/oak-core/src/main/java/org/apache/jackrabbit/mk/wrapper/BranchMergeMicroKernel.java
Added:
jackrabbit/oak/trunk/oak-core/src/main/java/org/apache/jackrabbit/mk/wrapper/BranchMergeMicroKernel.java
URL:
http://svn.apache.org/viewvc/jackrabbit/oak/trunk/oak-core/src/main/java/org/apache/jackrabbit/mk/wrapper/BranchMergeMicroKernel.java?rev=1371198&view=auto
==============================================================================
---
jackrabbit/oak/trunk/oak-core/src/main/java/org/apache/jackrabbit/mk/wrapper/BranchMergeMicroKernel.java
(added)
+++
jackrabbit/oak/trunk/oak-core/src/main/java/org/apache/jackrabbit/mk/wrapper/BranchMergeMicroKernel.java
Thu Aug 9 13:18:57 2012
@@ -0,0 +1,216 @@
+/*
+ * 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.jackrabbit.mk.wrapper;
+
+import java.io.InputStream;
+import java.util.HashSet;
+import org.apache.jackrabbit.mk.api.MicroKernel;
+import org.apache.jackrabbit.mk.api.MicroKernelException;
+
+/**
+ * A MicroKernel wrapper that provides limited support for branch and merge
even
+ * if the underlying implementation does not support it.
+ */
+public class BranchMergeMicroKernel implements MicroKernel {
+
+ private static final String TRUNK = "trunk";
+
+ private final MicroKernel base;
+ private final HashSet<String> knownBranches = new HashSet<String>();
+ private int nextBranch;
+ private String trunkHeadRevision;
+ private String busyBranch;
+
+ public BranchMergeMicroKernel(MicroKernel base) {
+ this.base = base;
+ }
+
+ @Override
+ public synchronized String branch(String trunkRevisionId) {
+ if (trunkRevisionId == null) {
+ trunkRevisionId = getHeadRevision();
+ }
+ String head = base.getHeadRevision();
+ String branchId = getBranchId(trunkRevisionId);
+ if (!TRUNK.equals(branchId)) {
+ throw new MicroKernelException("Cannot branch off a branch: "
+ + trunkRevisionId);
+ }
+ trunkHeadRevision = head;
+ String branch = "b" + nextBranch++;
+ knownBranches.add(branch);
+ String branchRev = branch + "-" + getHeadRevision();
+ busyBranch = null;
+ return branchRev;
+ }
+
+ private synchronized boolean isKnownBranch(String branchId) {
+ if (TRUNK.equals(branchId)) {
+ return false;
+ }
+ return knownBranches.contains(branchId);
+ }
+
+ private static String getBranchId(String revisionId) {
+ int idx = revisionId.indexOf('-');
+ if (idx <= 0) {
+ return TRUNK;
+ }
+ return revisionId.substring(0, idx);
+ }
+
+ private static String getRevisionId(String branchId, String revisionId) {
+ if (TRUNK.equals(branchId)) {
+ return revisionId;
+ }
+ return revisionId.substring(branchId.length() + 1);
+ }
+
+ private static String getCombinedRevisionId(String branchId,
+ String revisionId) {
+ if (TRUNK.equals(branchId)) {
+ return revisionId;
+ }
+ return branchId + "-" + revisionId;
+ }
+
+ @Override
+ public synchronized String commit(String path, String jsonDiff,
+ String revisionId, String message) {
+ if (revisionId == null) {
+ revisionId = getHeadRevision();
+ }
+ String branchId = getBranchId(revisionId);
+ // if another branch is active, wait until it's changes are merged
+ while (true) {
+ if (!TRUNK.equals(branchId) && !isKnownBranch(branchId)) {
+ throw new MicroKernelException("Unknown branch: " +
revisionId);
+ }
+ if (busyBranch == null || branchId.equals(busyBranch)) {
+ break;
+ }
+ try {
+ wait(1000);
+ } catch (InterruptedException e) {
+ // ignore
+ }
+ }
+ busyBranch = branchId;
+ String rev = getRevisionId(branchId, revisionId);
+ String rev2 = base.commit(path, jsonDiff, rev, message);
+ return getCombinedRevisionId(branchId, rev2);
+ }
+
+ @Override
+ public String diff(String fromRevisionId, String toRevisionId, String path,
+ int depth) {
+ String fromBranch = getBranchId(fromRevisionId);
+ String toBranch = getBranchId(toRevisionId);
+ String from = getRevisionId(fromBranch, fromRevisionId);
+ String to = getRevisionId(toBranch, toRevisionId);
+ return base.diff(from, to, path, depth);
+ }
+
+ @Override
+ public long getChildNodeCount(String path, String revisionId) {
+ String branch = getBranchId(revisionId);
+ String rev = getRevisionId(branch, revisionId);
+ return getChildNodeCount(path, rev);
+ }
+
+ @Override
+ public String getHeadRevision() {
+ if (trunkHeadRevision != null) {
+ return trunkHeadRevision;
+ }
+ return base.getHeadRevision();
+ }
+
+ @Override
+ public String getJournal(String fromRevisionId, String toRevisionId,
+ String path) {
+ String fromBranch = getBranchId(fromRevisionId);
+ String toBranch = getBranchId(toRevisionId);
+ if (!fromBranch.equals(TRUNK) || !toBranch.equals(TRUNK)) {
+ throw new MicroKernelException(
+ "This operation is not supported on branches: "
+ + fromRevisionId + " - " + toRevisionId);
+ }
+ return base.getJournal(fromRevisionId, toRevisionId, path);
+ }
+
+ @Override
+ public long getLength(String blobId) {
+ return base.getLength(blobId);
+ }
+
+ @Override
+ public String getNodes(String path, String revisionId, int depth,
+ long offset, int maxChildNodes, String filter) {
+ String branch = getBranchId(revisionId);
+ String rev = getRevisionId(branch, revisionId);
+ return base.getNodes(path, rev, depth, offset, maxChildNodes, filter);
+ }
+
+ @Override
+ public String getRevisionHistory(long since, int maxEntries, String path) {
+ return base.getRevisionHistory(since, maxEntries, path);
+ }
+
+ @Override
+ public String merge(String branchRevisionId, String message) {
+ String branch = getBranchId(branchRevisionId);
+ if (TRUNK.equals(branch)) {
+ throw new MicroKernelException("Can not merge the trunk");
+ }
+ knownBranches.remove(branch);
+ busyBranch = null;
+ trunkHeadRevision = null;
+ return getHeadRevision();
+ }
+
+ @Override
+ public boolean nodeExists(String path, String revisionId) {
+ String branch = getBranchId(revisionId);
+ String rev = getRevisionId(branch, revisionId);
+ return base.nodeExists(path, rev);
+ }
+
+ @Override
+ public int read(String blobId, long pos, byte[] buff, int off, int length)
{
+ return base.read(blobId, pos, buff, off, length);
+ }
+
+ @Override
+ public String waitForCommit(String oldHeadRevisionId, long timeout)
+ throws InterruptedException {
+ String branch = getBranchId(oldHeadRevisionId);
+ String rev = getRevisionId(branch, oldHeadRevisionId);
+ return base.waitForCommit(rev, timeout);
+ }
+
+ @Override
+ public String write(InputStream in) {
+ return base.write(in);
+ }
+
+ @Override
+ public String toString() {
+ return getClass().getName() + ":" + base;
+ }
+
+}
