private DataTree convertThisSnapShot() throws IOException {
// create a datatree
DataTree dataTree = new DataTree();
DataNodeV1 oldDataNode = oldDataTree.getNode("");
if (oldDataNode == null) {
// should never happen
LOG.error("Upgrading from an empty snapshot.");
}
recurseThroughDataTree(dataTree, "");
dataTree.lastProcessedZxid = oldDataTree.lastProcessedZxid;
return dataTree;
}
/**
* deseriluize from an inputarchive
*
* @param oldTree the tree to be created
* @param ia the input archive to be read from
* @param sessions the sessions to be created
* @throws IOException
*/
private void deserializeSnapshot(DataTreeV1 oldTree, InputArchive ia, Map<Long, Integer> sessions)
throws IOException {
int count = ia.readInt("count");
while (count > 0) {
long id = ia.readLong("id");
int to = ia.readInt("timeout");
sessions.put(id, to);
if (LOG.isTraceEnabled()) {
ZooTrace.logTraceMessage(
LOG,
ZooTrace.SESSION_TRACE_MASK,
"loadData --- session in archive: " + id + " with timeout: " + to);
}
count--;
}
oldTree.deserialize(ia, "tree");
}
/**
* recurse through the old datatree and construct the new data tree
*
* @param dataTree the new datatree to be constructed
* @param path the path to start with
*/
private void recurseThroughDataTree(DataTree dataTree, String path) {
if (path == null) return;
DataNodeV1 oldDataNode = oldDataTree.getNode(path);
HashSet<String> children = oldDataNode.children;
DataNode parent = null;
if ("".equals(path)) {
parent = null;
} else {
int lastSlash = path.lastIndexOf('/');
String parentPath = path.substring(0, lastSlash);
parent = dataTree.getNode(parentPath);
}
DataNode thisDatNode = convertDataNode(dataTree, parent, oldDataNode);
dataTree.addDataNode(path, thisDatNode);
if (children == null || children.size() == 0) {
return;
} else {
for (String child : children) {
recurseThroughDataTree(dataTree, path + "/" + child);
}
}
}
/**
* play the log from this logstream into the datatree
*
* @param logStream
* @return
* @throws IOException
*/
public long playLog(InputArchive logStream) throws IOException {
long highestZxid = 0;
try {
while (true) {
byte[] bytes = logStream.readBuffer("txnEntry");
if (bytes.length == 0) {
// Since we preallocate, we define EOF to be an
// empty transaction
throw new EOFException();
}
InputArchive ia = BinaryInputArchive.getArchive(new ByteArrayInputStream(bytes));
TxnHeader hdr = new TxnHeader();
Record txn = SerializeUtils.deserializeTxn(ia, hdr);
if (logStream.readByte("EOR") != 'B') {
LOG.warn("Last transaction was partial.");
throw new EOFException("Last transaction was partial.");
}
if (hdr.getZxid() <= highestZxid && highestZxid != 0) {
LOG.error(
highestZxid
+ "(higestZxid) >= "
+ hdr.getZxid()
+ "(next log) for type "
+ hdr.getType());
} else {
highestZxid = hdr.getZxid();
}
switch (hdr.getType()) {
case OpCode.createSession:
sessionsWithTimeouts.put(hdr.getClientId(), ((CreateSessionTxn) txn).getTimeOut());
if (LOG.isTraceEnabled()) {
ZooTrace.logTraceMessage(
LOG,
ZooTrace.SESSION_TRACE_MASK,
"playLog --- create session in log: 0x"
+ Long.toHexString(hdr.getClientId())
+ " with timeout: "
+ ((CreateSessionTxn) txn).getTimeOut());
}
// give dataTree a chance to sync its lastProcessedZxid
oldDataTree.processTxn(hdr, txn);
break;
case OpCode.closeSession:
sessionsWithTimeouts.remove(hdr.getClientId());
if (LOG.isTraceEnabled()) {
ZooTrace.logTraceMessage(
LOG,
ZooTrace.SESSION_TRACE_MASK,
"playLog --- close session in log: 0x" + Long.toHexString(hdr.getClientId()));
}
oldDataTree.processTxn(hdr, txn);
break;
default:
oldDataTree.processTxn(hdr, txn);
}
Request r = new Request(null, 0, hdr.getCxid(), hdr.getType(), null, null);
r.txn = txn;
r.hdr = hdr;
r.zxid = hdr.getZxid();
}
} catch (EOFException e) {
// expected in some cases - see comments in try block
}
return highestZxid;
}