StreamingFailoverDao.java

/**
 * Copyright (C) 2014 Stratio (http://stratio.com)
 *
 * 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.stratio.decision.dao;

import com.google.gson.Gson;
import com.stratio.decision.commons.constants.STREAMING;
import com.stratio.decision.configuration.ConfigurationContext;
import com.stratio.decision.model.FailoverPersistenceStoreModel;
import com.stratio.decision.utils.ZKUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

public class StreamingFailoverDao  {

    private static final Logger log = LoggerFactory.getLogger(StreamingFailoverDao.class);

    private ZKUtils zkutils;

    private Gson gson;

    private String zkPath;

    public StreamingFailoverDao(ConfigurationContext configurationContext, Gson gson) throws Exception {
        this.gson = gson;
        this.zkutils = ZKUtils.getZKUtils(configurationContext.getZookeeperHostsQuorum());

        zkPath = STREAMING.ZK_BASE_PATH.concat(STREAMING.ZK_PERSISTENCE_NODE);
    }


    public FailoverPersistenceStoreModel load() throws Exception {
        if (zkutils.existZNode(zkPath)) {
            log.info("Failover loading data...");
            byte[] bytes = zkutils.getZNode(zkPath);
            return gson.fromJson(new String(bytes), FailoverPersistenceStoreModel.class);
//            return new FailoverPersistenceStoreModel(bytes);
        } else {
            return null;
        }
    }

    public void save(FailoverPersistenceStoreModel failoverPersistenceStoreModel) throws Exception {
        log.info("Failover data to save. HASH {}, TOSTRING {} ", failoverPersistenceStoreModel.hashCode(),
                failoverPersistenceStoreModel);
//        zkutils.createZNode(STREAMING.ZK_PERSISTENCE_STORE_PATH, gson.toJson(failoverPersistenceStoreModel).getBytes());
        zkutils.createZNode(zkPath, gson.toJson(failoverPersistenceStoreModel).getBytes());
    }

}