private void waitForNewProcedures() {
// watch for new procedues that we need to start subprocedures for
LOG.debug("Looking for new procedures under znode:'" + zkController.getAcquiredBarrier() + "'");
List<String> runningProcedures = null;
try {
runningProcedures =
ZKUtil.listChildrenAndWatchForNewChildren(
zkController.getWatcher(), zkController.getAcquiredBarrier());
if (runningProcedures == null) {
LOG.debug("No running procedures.");
return;
}
} catch (KeeperException e) {
member.controllerConnectionFailure(
"General failure when watching for new procedures", e, null);
}
if (runningProcedures == null) {
LOG.debug("No running procedures.");
return;
}
for (String procName : runningProcedures) {
// then read in the procedure information
String path = ZKUtil.joinZNode(zkController.getAcquiredBarrier(), procName);
startNewSubprocedure(path);
}
}
/**
* Get the list of all the region servers from the specified peer
*
* @param zkw zk connection to use
* @return list of region server addresses or an empty list if the slave is unavailable
*/
private static List<ServerName> fetchSlavesAddresses(ZooKeeperWatcher zkw)
throws KeeperException {
List<String> children = ZKUtil.listChildrenAndWatchForNewChildren(zkw, zkw.rsZNode);
if (children == null) {
return Collections.emptyList();
}
List<ServerName> addresses = new ArrayList<ServerName>(children.size());
for (String child : children) {
addresses.add(ServerName.parseServerName(child));
}
return addresses;
}
private void watchForAbortedProcedures() {
LOG.debug("Checking for aborted procedures on node: '" + zkController.getAbortZnode() + "'");
try {
// this is the list of the currently aborted procedues
for (String node :
ZKUtil.listChildrenAndWatchForNewChildren(
zkController.getWatcher(), zkController.getAbortZnode())) {
String abortNode = ZKUtil.joinZNode(zkController.getAbortZnode(), node);
abort(abortNode);
}
} catch (KeeperException e) {
member.controllerConnectionFailure(
"Failed to list children for abort node:" + zkController.getAbortZnode(), e, null);
}
}
private List<String> getTaskList() throws InterruptedException {
List<String> childrenPaths = null;
long sleepTime = 1000;
// It will be in loop till it gets the list of children or
// it will come out if worker thread exited.
while (!shouldStop) {
try {
childrenPaths = ZKUtil.listChildrenAndWatchForNewChildren(watcher, watcher.splitLogZNode);
if (childrenPaths != null) {
return childrenPaths;
}
} catch (KeeperException e) {
LOG.warn("Could not get children of znode " + watcher.splitLogZNode, e);
}
LOG.debug(
"Retry listChildren of znode "
+ watcher.splitLogZNode
+ " after sleep for "
+ sleepTime
+ "ms!");
Thread.sleep(sleepTime);
}
return childrenPaths;
}