org.midonet.cluster.backend.zookeeper.SessionUnawareConnectionWatcher.java Source code

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Here is the source code for org.midonet.cluster.backend.zookeeper.SessionUnawareConnectionWatcher.java

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/*
 * Copyright 2015 Midokura SARL
 *
 * 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.midonet.cluster.backend.zookeeper;

import org.apache.commons.lang.NotImplementedException;
import org.apache.zookeeper.KeeperException;
import org.apache.zookeeper.WatchedEvent;
import org.apache.zookeeper.Watcher;
import org.slf4j.Logger;

import static org.slf4j.LoggerFactory.getLogger;

/**
 * Zookeeper connection watcher for the API server.
 */
public class SessionUnawareConnectionWatcher implements ZkConnectionAwareWatcher {

    private final static Logger log = getLogger(SessionUnawareConnectionWatcher.class);
    private ZkConnection conn;

    @Override
    synchronized public void process(WatchedEvent watchedEvent) {
        log.debug("ZookeeperConnWatcher.process: Entered with event {}", watchedEvent.getState());

        // The ZK client re-connects automatically. However, after it
        // successfully reconnects, if the session had expired, we need to
        // create a new session.
        if (watchedEvent.getState() == Watcher.Event.KeeperState.Expired && conn != null) {
            log.info("Session expired, reconnecting to ZK with a new session");
            try {
                conn.reopen();
            } catch (Exception e) {
                throw new RuntimeException("Zookeeper could not be " + "restarted", e);
            }
        }

        log.debug("ZookeeperConnWatcher.process: Exiting");
    }

    @Override
    public void setZkConnection(ZkConnection conn) {
        this.conn = conn;
    }

    @Override
    public void scheduleOnReconnect(Runnable runnable) {
        throw new NotImplementedException();
    }

    @Override
    public void scheduleOnDisconnect(Runnable runnable) {
        throw new NotImplementedException();
    }

    @Override
    public void handleError(String operationDesc, Runnable retry, KeeperException e) {
        log.warn("handleError(): ignoring: {}", e);
    }

    @Override
    public void handleError(String operationDesc, Runnable retry, StateAccessException e) {
        log.warn("handleError(): ignoring: {}", e);
    }

    @Override
    public void handleTimeout(Runnable runnable) {
        // do nothing
    }

    @Override
    public void handleDisconnect(Runnable runnable) {
        // do nothing
    }
}