interactivespaces.network.client.internal.ros.RosNetworkInformationClient.java Source code

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Here is the source code for interactivespaces.network.client.internal.ros.RosNetworkInformationClient.java

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/*
 * Copyright (C) 2012 Google Inc.
 *
 * 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 interactivespaces.network.client.internal.ros;

import com.google.common.collect.ArrayListMultimap;
import com.google.common.collect.Lists;
import com.google.common.collect.Multimap;
import com.google.common.collect.Sets;

import interactivespaces.master.server.services.internal.ros.MasterRosContext;
import interactivespaces.network.NetworkNodeInformation;
import interactivespaces.network.NetworkTopicInformation;
import interactivespaces.network.client.NetworkInformationClient;

import org.apache.commons.logging.Log;
import org.ros.master.client.MasterStateClient;
import org.ros.master.client.SystemState;
import org.ros.master.client.TopicSystemState;

import java.util.Collections;
import java.util.Comparator;
import java.util.List;
import java.util.Set;

/**
 * Obtain information from the ROS network.
 *
 * @author Keith M. Hughes
 */
public class RosNetworkInformationClient implements NetworkInformationClient {

    /**
     * ROS context for the master.
     */
    private MasterRosContext masterRosContext;

    /**
     * Client for getting information about the state of the network from the
     * master.
     */
    private MasterStateClient masterStateClient;

    /**
     * Comparator for comparing strings with each other.
     */
    private Comparator<String> lowerCaseStringComparator;

    /**
     * Logger for this client.
     */
    private Log log;

    /**
     * Comparator for comparing {@link NetworkTopicInformation} with each other.
     */
    private Comparator<NetworkTopicInformation> networkTopicInformationComparator;

    /**
     * Comparator for comparing {@link NetworkNodeInformation} with each other.
     */
    private Comparator<NetworkNodeInformation> networkNodeInformationComparator;

    public RosNetworkInformationClient() {
        lowerCaseStringComparator = new Comparator<String>() {

            @Override
            public int compare(String o1, String o2) {
                return o1.compareToIgnoreCase(o2);
            }
        };

        networkTopicInformationComparator = new Comparator<NetworkTopicInformation>() {

            @Override
            public int compare(NetworkTopicInformation o1, NetworkTopicInformation o2) {
                return o1.getTopicName().compareToIgnoreCase(o2.getTopicName());
            }
        };

        networkNodeInformationComparator = new Comparator<NetworkNodeInformation>() {

            @Override
            public int compare(NetworkNodeInformation o1, NetworkNodeInformation o2) {
                return o1.getNodeName().compareToIgnoreCase(o2.getNodeName());
            }
        };
    }

    @Override
    public void startup() {
        masterStateClient = new MasterStateClient(masterRosContext.getNode(),
                masterRosContext.getRosEnvironment().getMasterUri());
    }

    @Override
    public void shutdown() {
        masterStateClient = null;
    }

    @Override
    public List<NetworkTopicInformation> getTopics() {
        List<NetworkTopicInformation> topics = collectTopics();

        Collections.sort(topics, networkTopicInformationComparator);

        return topics;
    }

    /**
     * Make a call to the master and return all topics on the master.
     *
     * @return a potentially unsorted list of topics on the master
     */
    private List<NetworkTopicInformation> collectTopics() {
        List<NetworkTopicInformation> topics = Lists.newArrayList();
        SystemState systemState = masterStateClient.getSystemState();

        for (TopicSystemState topicState : systemState.getTopics()) {
            List<String> publishers = Lists.newArrayList(topicState.getPublishers());
            Collections.sort(publishers, lowerCaseStringComparator);

            List<String> subscribers = Lists.newArrayList(topicState.getSubscribers());
            Collections.sort(subscribers, lowerCaseStringComparator);

            topics.add(new NetworkTopicInformation(topicState.getTopicName(), publishers, subscribers));
        }

        return topics;
    }

    @Override
    public List<NetworkNodeInformation> getNodes() {
        List<NetworkNodeInformation> nodes = collectNodes();

        Collections.sort(nodes, networkNodeInformationComparator);

        return nodes;
    }

    /**
     * Make a call to the master and return all topics on the master.
     *
     * @return a potentially unsorted list of topics on the master
     */
    private List<NetworkNodeInformation> collectNodes() {
        List<NetworkNodeInformation> nodes = Lists.newArrayList();

        // maps from node name to the appropriate topic type
        Multimap<String, String> publishers = ArrayListMultimap.create();
        Multimap<String, String> subscribers = ArrayListMultimap.create();

        SystemState systemState = masterStateClient.getSystemState();
        for (TopicSystemState topicState : systemState.getTopics()) {
            String topicName = topicState.getTopicName();
            for (String publisher : topicState.getPublishers()) {
                publishers.put(publisher, topicName);
            }
            for (String subscriber : topicState.getSubscribers()) {
                subscribers.put(subscriber, topicName);
            }

        }

        Set<String> nodesSeen = Sets.newHashSet();
        for (String nodeName : publishers.keySet()) {
            nodesSeen.add(nodeName);

            List<String> publisherTopics = Lists.newArrayList(publishers.get(nodeName));
            Collections.sort(publisherTopics, lowerCaseStringComparator);

            List<String> subscriberTopics = Lists.newArrayList(subscribers.get(nodeName));
            Collections.sort(subscriberTopics, lowerCaseStringComparator);

            nodes.add(new NetworkNodeInformation(nodeName, publisherTopics, subscriberTopics));
        }

        for (String nodeName : subscribers.keySet()) {
            if (nodesSeen.contains(nodeName)) {
                continue;
            }

            // No publisher topics or would have gotten above.
            List<String> publisherTopics = Lists.newArrayList();

            List<String> subscriberTopics = Lists.newArrayList(subscribers.get(nodeName));
            Collections.sort(subscriberTopics, lowerCaseStringComparator);

            nodes.add(new NetworkNodeInformation(nodeName, publisherTopics, subscriberTopics));
        }

        return nodes;
    }

    /**
     * @param masterRosContext
     *          the masterRosContext to set
     */
    public void setMasterRosContext(MasterRosContext masterRosContext) {
        this.masterRosContext = masterRosContext;
    }

    /**
     * @param log
     *          the log to set
     */
    public void setLog(Log log) {
        this.log = log;
    }
}