/**
* To create a ZooKeeper client object, the application needs to pass a connection string
* containing a comma separated list of host:port pairs, each corresponding to a ZooKeeper server.
*
* <p>Session establishment is asynchronous. This constructor will initiate connection to the
* server and return immediately - potentially (usually) before the session is fully established.
* The watcher argument specifies the watcher that will be notified of any changes in state. This
* notification can come at any point before or after the constructor call has returned.
*
* <p>The instantiated ZooKeeper client object will pick an arbitrary server from the
* connectString and attempt to connect to it. If establishment of the connection fails, another
* server in the connect string will be tried (the order is non-deterministic, as we random
* shuffle the list), until a connection is established. The client will continue attempts until
* the session is explicitly closed.
*
* <p>Added in 3.2.0: An optional "chroot" suffix may also be appended to the connection string.
* This will run the client commands while interpreting all paths relative to this root (similar
* to the unix chroot command).
*
* @param connectString comma separated host:port pairs, each corresponding to a zk server. e.g.
* "127.0.0.1:3000,127.0.0.1:3001,127.0.0.1:3002" If the optional chroot suffix is used the
* example would look like: "127.0.0.1:3000,127.0.0.1:3001,127.0.0.1:3002/app/a" where the
* client would be rooted at "/app/a" and all paths would be relative to this root - ie
* getting/setting/etc... "/foo/bar" would result in operations being run on "/app/a/foo/bar"
* (from the server perspective).
* @param sessionTimeout session timeout in milliseconds
* @param watcher a watcher object which will be notified of state changes, may also be notified
* for node events
* @throws IOException in cases of network failure
* @throws IllegalArgumentException if an invalid chroot path is specified
*/
public ZooKeeper(String connectString, int sessionTimeout, Watcher watcher) throws IOException {
LOG.info(
"Initiating client connection, connectString="
+ connectString
+ " sessionTimeout="
+ sessionTimeout
+ " watcher="
+ watcher);
watchManager.defaultWatcher = watcher;
cnxn = new ClientCnxn(connectString, sessionTimeout, this, watchManager);
cnxn.start();
}
/**
* To create a ZooKeeper client object, the application needs to pass a connection string
* containing a comma separated list of host:port pairs, each corresponding to a ZooKeeper server.
*
* <p>Session establishment is asynchronous. This constructor will initiate connection to the
* server and return immediately - potentially (usually) before the session is fully established.
* The watcher argument specifies the watcher that will be notified of any changes in state. This
* notification can come at any point before or after the constructor call has returned.
*
* <p>The instantiated ZooKeeper client object will pick an arbitrary server from the
* connectString and attempt to connect to it. If establishment of the connection fails, another
* server in the connect string will be tried (the order is non-deterministic, as we random
* shuffle the list), until a connection is established. The client will continue attempts until
* the session is explicitly closed (or the session is expired by the server).
*
* <p>Added in 3.2.0: An optional "chroot" suffix may also be appended to the connection string.
* This will run the client commands while interpreting all paths relative to this root (similar
* to the unix chroot command).
*
* <p>Use {@link #getSessionId} and {@link #getSessionPasswd} on an established client connection,
* these values must be passed as sessionId and sessionPasswd respectively if reconnecting.
* Otherwise, if not reconnecting, use the other constructor which does not require these
* parameters.
*
* @param connectString comma separated host:port pairs, each corresponding to a zk server. e.g.
* "127.0.0.1:3000,127.0.0.1:3001,127.0.0.1:3002" If the optional chroot suffix is used the
* example would look like: "127.0.0.1:3000,127.0.0.1:3001,127.0.0.1:3002/app/a" where the
* client would be rooted at "/app/a" and all paths would be relative to this root - ie
* getting/setting/etc... "/foo/bar" would result in operations being run on "/app/a/foo/bar"
* (from the server perspective).
* @param sessionTimeout session timeout in milliseconds
* @param watcher a watcher object which will be notified of state changes, may also be notified
* for node events
* @param sessionId specific session id to use if reconnecting
* @param sessionPasswd password for this session
* @throws IOException in cases of network failure
* @throws IllegalArgumentException if an invalid chroot path is specified
*/
public ZooKeeper(
String connectString,
int sessionTimeout,
Watcher watcher,
long sessionId,
byte[] sessionPasswd)
throws IOException {
LOG.info(
"Initiating client connection, connectString="
+ connectString
+ " sessionTimeout="
+ sessionTimeout
+ " watcher="
+ watcher
+ " sessionId="
+ sessionId
+ " sessionPasswd="
+ (sessionPasswd == null ? "<null>" : "<hidden>"));
watchManager.defaultWatcher = watcher;
cnxn =
new ClientCnxn(connectString, sessionTimeout, this, watchManager, sessionId, sessionPasswd);
cnxn.start();
}
/**
* Specify the default watcher for the connection (overrides the one specified during
* construction).
*
* @param watcher
*/
public synchronized void register(Watcher watcher) {
watchManager.defaultWatcher = watcher;
}
