/*
* (C) 2007-2012 Alibaba Group Holding Limited.
*
* 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.
* Authors:
* wuhua <wq163@163.com> , boyan <killme2008@gmail.com>
*/
package com.taobao.metamorphosis.utils;
import java.io.Serializable;
import java.io.UnsupportedEncodingException;
import java.util.List;
import org.I0Itec.zkclient.ZkClient;
import org.I0Itec.zkclient.exception.ZkMarshallingError;
import org.I0Itec.zkclient.exception.ZkNoNodeException;
import org.I0Itec.zkclient.exception.ZkNodeExistsException;
import org.I0Itec.zkclient.serialize.ZkSerializer;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
/**
* ��zk����������
*
* @author boyan
* @Date 2011-4-25
* @author wuhua
* @Date 2011-6-26
*/
public class ZkUtils {
private static Log logger = LogFactory.getLog(ZkUtils.class);
/**
* make sure a persiste.nt path exists in ZK. Create the path if not exist.
*/
public static void makeSurePersistentPathExists(final ZkClient client, final String path) throws Exception {
if (!client.exists(path)) {
try {
client.createPersistent(path, true);
}
catch (final ZkNodeExistsException e) {
}
catch (final Exception e) {
throw e;
}
}
}
/**
* create the parent path
*/
public static void createParentPath(final ZkClient client, final String path) throws Exception {
final String parentDir = path.substring(0, path.lastIndexOf('/'));
if (parentDir.length() != 0) {
client.createPersistent(parentDir, true);
}
}
/**
* Create an ephemeral node with the given path and data. Create parents if
* necessary.
*/
public static void createEphemeralPath(final ZkClient client, final String path, final String data)
throws Exception {
try {
client.createEphemeral(path, data);
}
catch (final ZkNoNodeException e) {
createParentPath(client, path);
client.createEphemeral(path, data);
}
}
/**
* Create an ephemeral node with the given path and data. Throw
* NodeExistException if node already exists.
*/
public static void createEphemeralPathExpectConflict(final ZkClient client, final String path, final String data)
throws Exception {
try {
createEphemeralPath(client, path, data);
}
catch (final ZkNodeExistsException e) {
// this canZkConfig happen when there is connection loss; make sure
// the data
// is what we intend to write
String storedData = null;
try {
storedData = readData(client, path);
}
catch (final ZkNoNodeException e1) {
// the node disappeared; treat as if node existed and let caller
// handles this
}
catch (final Exception e2) {
throw e2;
}
if (storedData == null || !storedData.equals(data)) {
throw e;
}
else {
// otherwise, the creation succeeded, return normally
logger.info(path + " exists with value " + data + " during connection loss; this is ok");
}
}
catch (final Exception e) {
throw e;
}
}
/**
* Update the value of a persistent node with the given path and data.
* create parrent directory if necessary. Never throw NodeExistException.
*/
public static void updatePersistentPath(final ZkClient client, final String path, final String data)
throws Exception {
try {
client.writeData(path, data);
}
catch (final ZkNoNodeException e) {
createParentPath(client, path);
client.createPersistent(path, data);
}
catch (final Exception e) {
throw e;
}
}
public static String readData(final ZkClient client, final String path) {
return client.readData(path);
}
public static String readDataMaybeNull(final ZkClient client, final String path) {
return client.readData(path, true);
}
/**
* Update the value of a persistent node with the given path and data.
* create parrent directory if necessary. Never throw NodeExistException.
*/
public static void updateEphemeralPath(final ZkClient client, final String path, final String data)
throws Exception {
try {
client.writeData(path, data);
}
catch (final ZkNoNodeException e) {
createParentPath(client, path);
client.createEphemeral(path, data);
}
catch (final Exception e) {
throw e;
}
}
public static void deletePath(final ZkClient client, final String path) throws Exception {
try {
client.delete(path);
}
catch (final ZkNoNodeException e) {
logger.info(path + " deleted during connection loss; this is ok");
}
catch (final Exception e) {
throw e;
}
}
public static void deletePathRecursive(final ZkClient client, final String path) throws Exception {
try {
client.deleteRecursive(path);
}
catch (final ZkNoNodeException e) {
logger.info(path + " deleted during connection loss; this is ok");
}
catch (final Exception e) {
throw e;
}
}
public static List<String> getChildren(final ZkClient client, final String path) {
return client.getChildren(path);
}
public static List<String> getChildrenMaybeNull(final ZkClient client, final String path) {
try {
return client.getChildren(path);
}
catch (final ZkNoNodeException e) {
return null;
}
}
/**
* Check if the given path exists
*/
public static boolean pathExists(final ZkClient client, final String path) {
return client.exists(path);
}
public static String getLastPart(final String path) {
if (path == null) {
return null;
}
final int index = path.lastIndexOf('/');
if (index >= 0) {
return path.substring(index + 1);
}
else {
return null;
}
}
public static class StringSerializer implements ZkSerializer {
@Override
public Object deserialize(final byte[] bytes) throws ZkMarshallingError {
try {
return new String(bytes, "utf-8");
}
catch (final UnsupportedEncodingException e) {
throw new ZkMarshallingError(e);
}
}
@Override
public byte[] serialize(final Object data) throws ZkMarshallingError {
try {
return ((String) data).getBytes("utf-8");
}
catch (final UnsupportedEncodingException e) {
throw new ZkMarshallingError(e);
}
}
}
public static class ZKConfig extends Config implements Serializable {
static final long serialVersionUID = -1L;
@Key(name = "zk.zkRoot")
public String zkRoot = "/meta";
/**
* If enable zookeeper
*/
@Key(name = "zk.zkEnable")
public boolean zkEnable = true;
/** ZK host string */
@Key(name = "zk.zkConnect")
public String zkConnect;
/** zookeeper session timeout */
@Key(name = "zk.zkSessionTimeoutMs")
public int zkSessionTimeoutMs = 30000;
/**
* the max time that the client waits to establish a connection to
* zookeeper
*/
@Key(name = "zk.zkConnectionTimeoutMs")
public int zkConnectionTimeoutMs = 30000;
/** how far a ZK follower can be behind a ZK leader */
@Key(name = "zk.zkSyncTimeMs")
public int zkSyncTimeMs = 5000;
public ZKConfig(final String zkConnect, final int zkSessionTimeoutMs, final int zkConnectionTimeoutMs,
final int zkSyncTimeMs) {
super();
this.zkConnect = zkConnect;
this.zkSessionTimeoutMs = zkSessionTimeoutMs;
this.zkConnectionTimeoutMs = zkConnectionTimeoutMs;
this.zkSyncTimeMs = zkSyncTimeMs;
}
public String getZkRoot() {
return this.zkRoot;
}
public void setZkRoot(String zkRoot) {
this.zkRoot = zkRoot;
}
public boolean isZkEnable() {
return this.zkEnable;
}
public void setZkEnable(boolean zkEnable) {
this.zkEnable = zkEnable;
}
public String getZkConnect() {
return this.zkConnect;
}
public void setZkConnect(String zkConnect) {
this.zkConnect = zkConnect;
}
public int getZkSessionTimeoutMs() {
return this.zkSessionTimeoutMs;
}
public void setZkSessionTimeoutMs(int zkSessionTimeoutMs) {
this.zkSessionTimeoutMs = zkSessionTimeoutMs;
}
public int getZkConnectionTimeoutMs() {
return this.zkConnectionTimeoutMs;
}
public void setZkConnectionTimeoutMs(int zkConnectionTimeoutMs) {
this.zkConnectionTimeoutMs = zkConnectionTimeoutMs;
}
public int getZkSyncTimeMs() {
return this.zkSyncTimeMs;
}
public void setZkSyncTimeMs(int zkSyncTimeMs) {
this.zkSyncTimeMs = zkSyncTimeMs;
}
public ZKConfig() {
super();
this.zkConnect = "localhost:2181";
}
@Override
public int hashCode() {
final int prime = 31;
int result = 1;
result = prime * result + (this.zkConnect == null ? 0 : this.zkConnect.hashCode());
result = prime * result + this.zkConnectionTimeoutMs;
result = prime * result + (this.zkEnable ? 1231 : 1237);
result = prime * result + (this.zkRoot == null ? 0 : this.zkRoot.hashCode());
result = prime * result + this.zkSessionTimeoutMs;
result = prime * result + this.zkSyncTimeMs;
return result;
}
@Override
public boolean equals(Object obj) {
if (this == obj) {
return true;
}
if (obj == null) {
return false;
}
if (this.getClass() != obj.getClass()) {
return false;
}
ZKConfig other = (ZKConfig) obj;
if (this.zkConnect == null) {
if (other.zkConnect != null) {
return false;
}
}
else if (!this.zkConnect.equals(other.zkConnect)) {
return false;
}
if (this.zkConnectionTimeoutMs != other.zkConnectionTimeoutMs) {
return false;
}
if (this.zkEnable != other.zkEnable) {
return false;
}
if (this.zkRoot == null) {
if (other.zkRoot != null) {
return false;
}
}
else if (!this.zkRoot.equals(other.zkRoot)) {
return false;
}
if (this.zkSessionTimeoutMs != other.zkSessionTimeoutMs) {
return false;
}
if (this.zkSyncTimeMs != other.zkSyncTimeMs) {
return false;
}
return true;
}
public ZKConfig(final String zkRoot, final String zkConnect, final int zkSessionTimeoutMs,
final int zkConnectionTimeoutMs, final int zkSyncTimeMs, final boolean zkEnable) {
super();
this.zkRoot = zkRoot;
this.zkConnect = zkConnect;
this.zkSessionTimeoutMs = zkSessionTimeoutMs;
this.zkConnectionTimeoutMs = zkConnectionTimeoutMs;
this.zkSyncTimeMs = zkSyncTimeMs;
this.zkEnable = zkEnable;
}
}
}