com.almende.eve.state.mongo.MongoStateBuilder.java Source code

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Here is the source code for com.almende.eve.state.mongo.MongoStateBuilder.java

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/*
 * Copyright: Almende B.V. (2014), Rotterdam, The Netherlands
 * License: The Apache Software License, Version 2.0
 */
package com.almende.eve.state.mongo;

import java.net.UnknownHostException;
import java.util.HashSet;
import java.util.Iterator;
import java.util.Map;
import java.util.Set;
import java.util.concurrent.ConcurrentHashMap;
import java.util.logging.Level;
import java.util.logging.Logger;

import org.jongo.Jongo;
import org.jongo.MongoCollection;

import com.almende.eve.capabilities.AbstractCapabilityBuilder;
import com.almende.eve.state.State;
import com.almende.eve.state.StateService;
import com.fasterxml.jackson.databind.node.ObjectNode;
import com.mongodb.MongoClient;
import com.mongodb.MongoClientOptions;
import com.mongodb.ServerAddress;

/**
 * The Class MongoStateBuilder.
 */
public class MongoStateBuilder extends AbstractCapabilityBuilder<MongoState> {
    private static final Logger LOG = Logger.getLogger(MongoStateBuilder.class.getName());
    private static Map<String, MongoStateProvider> instances = new ConcurrentHashMap<String, MongoStateProvider>();

    @Override
    public MongoState build() {
        final MongoStateProvider provider = getInstanceByParams(getParams());
        if (provider != null) {
            return provider.get(getParams());
        } else {
            LOG.warning("Couldn't get MongoStateProvider instance!");
            return null;
        }
    }

    /**
     * Gets the instance by params.
     * 
     * @param params
     *            the params
     * @return the instance by params
     */
    public MongoStateProvider getInstanceByParams(final ObjectNode params) {
        final MongoStateConfig config = MongoStateConfig.decorate(params);
        final String key = config.getKey();

        if (instances.containsKey(key)) {
            return instances.get(key);
        } else {
            synchronized (instances) {
                if (!instances.containsKey(key)) {
                    try {

                        final MongoStateProvider result = new MongoStateProvider(params);
                        if (result != null) {
                            instances.put(key, result);
                        }
                    } catch (final UnknownHostException e) {
                        LOG.log(Level.WARNING, "Couldn't init MongoStateService", e);
                    }
                }
                return instances.get(key);
            }
        }
    }

    /**
     * A service for managing MemoryState objects.
     */
    public class MongoStateProvider implements StateService {

        /* internal attributes */
        private final Jongo jongo;
        private final String collectionName;

        /**
         * Instantiates a new mongo state service.
         * 
         * @param params
         *            the params
         * @throws UnknownHostException
         *             the unknown host exception
         */
        public MongoStateProvider(final ObjectNode params) throws UnknownHostException {

            final MongoStateConfig config = MongoStateConfig.decorate(params);

            // initialization of client & jongo
            final MongoClient client = createClient(config.getHost(), config.getPort());
            jongo = new Jongo(client.getDB(config.getDatabase()));
            collectionName = config.getCollection();

            jongo.runCommand("{collMod: '" + collectionName + "', usePowerOf2Sizes : true }");

        }

        private MongoClient createClient(final String databaseUri, final int port) throws UnknownHostException {
            final MongoClientOptions options = MongoClientOptions.builder().connectionsPerHost(100)
                    .threadsAllowedToBlockForConnectionMultiplier(1500).build();
            final MongoClient client = new MongoClient(new ServerAddress(databaseUri, port), options);
            return client;
        }

        /**
         * returns jongo collection used by this state factory.
         * 
         * @return the collection
         */
        public MongoCollection getCollection() {
            return jongo.getCollection(collectionName);
        }

        /**
         * Gets the.
         * 
         * @param params
         *            the params
         * @return the mongo state
         */
        public MongoState get(final ObjectNode params) {

            final MongoStateConfig config = MongoStateConfig.decorate(params);
            final String id = config.getId();

            MongoState result = null;
            try {
                synchronized (this) {
                    result = getCollection().findOne("{_id: #}", id).as(MongoState.class);
                    if (result == null) {
                        result = new MongoState(id, this, params);
                        getCollection().insert(result);
                    } else {
                        result.setService(this);
                    }
                }
                result.setCollection(getCollection());
            } catch (final Exception e) {
                LOG.log(Level.WARNING, "get error", e);
            }
            return result;
        }

        /*
         * (non-Javadoc)
         * @see
         * com.almende.eve.state.StateService#delete(com.almende.eve.state.State)
         */
        @Override
        public void delete(final State instance) {
            try {
                getCollection().remove("{_id: #}", instance.getId());
            } catch (final Exception e) {
                LOG.log(Level.WARNING, "delete error", e);
            }
        }

        @Override
        public Set<String> getStateIds() {
            Iterator<MongoState> res = getCollection().find().as(MongoState.class).iterator();
            Set<String> result = new HashSet<String>();
            while (res.hasNext()) {
                MongoState state = res.next();
                result.add(state.getId());
            }
            return result;
        }
    }
}