/**
* Copyright 2010 the original author or authors.
*
* Licensed 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.I0Itec.zkclient;
import java.io.IOException;
import java.util.List;
import java.util.concurrent.locks.Lock;
import java.util.concurrent.locks.ReentrantLock;
import org.I0Itec.zkclient.exception.ZkException;
import org.apache.log4j.Logger;
import org.apache.zookeeper.CreateMode;
import org.apache.zookeeper.KeeperException;
import org.apache.zookeeper.Watcher;
import org.apache.zookeeper.ZooDefs.Ids;
import org.apache.zookeeper.ZooKeeper;
import org.apache.zookeeper.ZooKeeper.States;
import org.apache.zookeeper.data.ACL;
import org.apache.zookeeper.data.Stat;
public class ZkConnection implements IZkConnection {
private static final Logger LOG = Logger.getLogger(ZkConnection.class);
/** It is recommended to use quite large sessions timeouts for ZooKeeper. */
private static final int DEFAULT_SESSION_TIMEOUT = 30000;
private ZooKeeper _zk = null;
private Lock _zookeeperLock = new ReentrantLock();
private final String _servers;
private final int _sessionTimeOut;
public ZkConnection(String zkServers) {
this(zkServers, DEFAULT_SESSION_TIMEOUT);
}
public ZkConnection(String zkServers, int sessionTimeOut) {
_servers = zkServers;
_sessionTimeOut = sessionTimeOut;
}
@Override
public void connect(Watcher watcher) {
_zookeeperLock.lock();
try {
if (_zk != null) {
throw new IllegalStateException("zk client has already been started");
}
try {
LOG.debug("Creating new ZookKeeper instance to connect to " + _servers + ".");
_zk = new ZooKeeper(_servers, _sessionTimeOut, watcher);
} catch (IOException e) {
throw new ZkException("Unable to connect to " + _servers, e);
}
} finally {
_zookeeperLock.unlock();
}
}
public void close() throws InterruptedException {
_zookeeperLock.lock();
try {
if (_zk != null) {
LOG.debug("Closing ZooKeeper connected to " + _servers);
_zk.close();
_zk = null;
}
} finally {
_zookeeperLock.unlock();
}
}
public String create(String path, byte[] data, CreateMode mode) throws KeeperException, InterruptedException {
return _zk.create(path, data, Ids.OPEN_ACL_UNSAFE, mode);
}
@Override
public String create(String path, byte[] data, List<ACL> acl, CreateMode mode) throws KeeperException, InterruptedException {
return _zk.create(path, data, acl, mode);
}
public void delete(String path) throws InterruptedException, KeeperException {
_zk.delete(path, -1);
}
public boolean exists(String path, boolean watch) throws KeeperException, InterruptedException {
return _zk.exists(path, watch) != null;
}
public List<String> getChildren(final String path, final boolean watch) throws KeeperException, InterruptedException {
return _zk.getChildren(path, watch);
}
public byte[] readData(String path, Stat stat, boolean watch) throws KeeperException, InterruptedException {
return _zk.getData(path, watch, stat);
}
public void writeData(String path, byte[] data) throws KeeperException, InterruptedException {
writeData(path, data, -1);
}
public void writeData(String path, byte[] data, int version) throws KeeperException, InterruptedException {
_zk.setData(path, data, version);
}
public Stat writeDataReturnStat(String path, byte[] data, int version) throws KeeperException, InterruptedException {
return _zk.setData(path, data, version);
}
public States getZookeeperState() {
return _zk != null ? _zk.getState() : null;
}
public ZooKeeper getZookeeper() {
return _zk;
}
@Override
public long getCreateTime(String path) throws KeeperException, InterruptedException {
Stat stat = _zk.exists(path, false);
if (stat != null) {
return stat.getCtime();
}
return -1;
}
@Override
public String getServers() {
return _servers;
}
@Override
public void addAuthInfo(String scheme, byte[] auth) {
_zk.addAuthInfo(scheme, auth);
}
}