com.servioticy.queueclient.KestrelMemcachedClient.java Source code

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Here is the source code for com.servioticy.queueclient.KestrelMemcachedClient.java

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/*******************************************************************************
 * Copyright 2014 Barcelona Supercomputing Center (BSC)
 *
 * 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.servioticy.queueclient;

import net.spy.memcached.*;
import org.apache.commons.configuration.HierarchicalConfiguration;

import java.io.IOException;

/**
 * @author ?lvaro Villalba Navarro <alvaro.villalba@bsc.es>
 * 
 */
public class KestrelMemcachedClient extends QueueClient {

    private int expire = 0;

    MemcachedClient kestrelClient;

    public KestrelMemcachedClient() {
    }

    public void setExpire(int expire) {
        this.expire = expire;
    }

    public int getExpire() {
        return expire;
    }

    @Override
    protected boolean putImpl(Object item) {
        try {
            // This is blocking by now
            return kestrelClient.set(this.getRelativeAddress(), expire, item).get();
        } catch (Exception e) {
            logger.error("KestrelMemcached put failed ({})", e.getMessage());
            return false;
        }

    }

    @Override
    protected Object getImpl() {
        return kestrelClient.get(this.getRelativeAddress());

    }

    @Override
    protected void connectImpl() throws QueueClientException {
        if (kestrelClient != null) {
            return;
        }
        try {
            ConnectionFactoryBuilder builder = new ConnectionFactoryBuilder();
            // VERY IMPORTANT! Otherwise, spymemcached optimizes away concurrent gets
            builder.setShouldOptimize(false);
            // Retry upon failure
            builder.setFailureMode(FailureMode.Retry);
            ConnectionFactory memcachedConnectionFactory = builder.build();
            kestrelClient = new MemcachedClient(memcachedConnectionFactory,
                    AddrUtil.getAddresses(this.getBaseAddress()));
        } catch (IOException e) {
            kestrelClient = null;
            String errMsg = "Unable to connect to the queue (" + e.getMessage() + ").";
            logger.error(errMsg);
            throw new QueueClientException(errMsg);
        }
    }

    @Override
    protected void disconnectImpl() {
        if (kestrelClient == null) {
            return;
        }

        kestrelClient.shutdown();

        kestrelClient = null;
    }

    @Override
    protected void init(HierarchicalConfiguration config) throws QueueClientException {
        checkBaseAddress();
        checkRelativeAddress();
        // If config is null, just load the defaults.
        if (config == null) {
            config = new HierarchicalConfiguration();
        }
        this.expire = config.getInt("expire", 0);
    }

    private void checkBaseAddress() throws QueueClientException {
        if (this.getBaseAddress() == null) {
            String errMsg = "Malformed configuration file: No servers defined for KestrelMemcachedClient (baseAddress).";
            logger.error(errMsg);
            throw new QueueClientException(errMsg);
        }
    }

    private void checkRelativeAddress() throws QueueClientException {
        if (this.getRelativeAddress() == null) {
            String errMsg = "Malformed configuration file: No queue name defined for KestrelMemcachedClient (relativeAddress).";
            logger.error(errMsg);
            throw new QueueClientException(errMsg);
        }
    }

}