com.gxl.zk.ZKConnectionManager.java Source code

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Here is the source code for com.gxl.zk.ZKConnectionManager.java

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/*
 * Copyright 2015-2101 gaoxianglong
 *
 * 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 com.gxl.zk;

import java.util.concurrent.CountDownLatch;
import org.apache.zookeeper.CreateMode;
import org.apache.zookeeper.WatchedEvent;
import org.apache.zookeeper.Watcher;
import org.apache.zookeeper.Watcher.Event.KeeperState;
import org.apache.zookeeper.ZooDefs.Ids;
import org.apache.zookeeper.ZooKeeper;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import com.gxl.core.tracing.TraceFilter;
import com.sharksharding.exception.ConnectionException;

/**
 * ?,zookeeper?session?
 * 
 * @author gaoxianglong
 */
public class ZKConnectionManager {
    private String address;
    private int zk_session_timeout;
    private String samplingRate_path;
    private CountDownLatch countDownLatch;
    private ZooKeeper zk_client;
    private Logger logger = LoggerFactory.getLogger(ZKConnectionManager.class);

    /**
     * ?
     *
     * @author gaoxianglong
     */
    public void init() {
        connection();
    }

    /**
     * zookeeper
     * 
     * @author gaoxianglong
     * 
     * @throws ConnectionException
     * 
     * @return void
     */
    private void connection() {
        countDownLatch = new CountDownLatch(1);
        try {
            zk_client = new ZooKeeper(address, zk_session_timeout, new Watcher() {
                @Override
                public void process(WatchedEvent event) {
                    final KeeperState STATE = event.getState();
                    switch (STATE) {
                    case SyncConnected:
                        countDownLatch.countDown();
                        logger.info("connection zookeeper success");
                        break;
                    case Disconnected:
                        logger.warn("zookeeper connection is disconnected");
                        break;
                    case Expired:
                        logger.error("zookeeper session expired");
                        break;
                    case AuthFailed:
                        logger.error("authentication failure");
                    default:
                        break;
                    }
                }
            });
            countDownLatch.await();
            String samplingRate = null;
            /* ?? */
            if (null == zk_client.exists("/tracing", false)) {
                zk_client.create("/tracing", new byte[0], Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT);
            }
            /* ?znode? */
            if (null != zk_client.exists(samplingRate_path, false)) {
                samplingRate = new String(zk_client.getData(samplingRate_path,
                        new SamplingRateWatcher(zk_client, samplingRate_path), null));
            } else {
                logger.warn("-->" + samplingRate_path + "?,");
                /* ?1/1024 */
                zk_client.create(samplingRate_path, "1024".getBytes(), Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT);
                samplingRate = new String(zk_client.getData(samplingRate_path,
                        new SamplingRateWatcher(zk_client, samplingRate_path), null));
            }
            /*  */
            TraceFilter.samplingNum = Integer.parseInt(samplingRate);
        } catch (Exception e) {
            logger.error("error", e);
        }
    }

    public int getZk_session_timeout() {
        return zk_session_timeout;
    }

    public void setZk_session_timeout(int zk_session_timeout) {
        this.zk_session_timeout = zk_session_timeout;
    }

    public String getSamplingRate_path() {
        return samplingRate_path;
    }

    public void setSamplingRate_path(String samplingRate_path) {
        this.samplingRate_path = samplingRate_path;
    }

    public String getAddress() {
        return address;
    }

    public void setAddress(String address) {
        this.address = address;
    }
}