org.elasticdroid.model.MonitorInstanceModel.java Source code

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Here is the source code for org.elasticdroid.model.MonitorInstanceModel.java

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/**
 *  This file is part of ElasticDroid.
 *
 * ElasticDroid is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
    
 * ElasticDroid is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
    
 * You should have received a copy of the GNU General Public License
 * along with ElasticDroid.  If not, see <http://www.gnu.org/licenses/>.
 * 
 * Authored by siddhu on 30 Dec 2010
 */
package org.elasticdroid.model;

import java.util.Arrays;
import java.util.Collections;
import java.util.Comparator;
import java.util.Date;
import java.util.HashMap;
import java.util.List;

import org.elasticdroid.model.tpl.GenericModel;
import org.elasticdroid.tpl.GenericActivity;
import org.elasticdroid.tpl.GenericListActivity;
import org.elasticdroid.utils.AWSConstants;
import org.elasticdroid.utils.CloudWatchInput;

import android.util.Log;

import com.amazonaws.AmazonClientException;
import com.amazonaws.AmazonServiceException;
import com.amazonaws.auth.BasicAWSCredentials;
import com.amazonaws.services.cloudwatch.AmazonCloudWatchClient;
import com.amazonaws.services.cloudwatch.model.Datapoint;
import com.amazonaws.services.cloudwatch.model.Dimension;
import com.amazonaws.services.cloudwatch.model.GetMetricStatisticsRequest;
import com.amazonaws.services.cloudwatch.model.GetMetricStatisticsResult;

/**
 * Retrieve the metric required, and return an Object.
 * @author siddhu
 *
 * 30 Dec 2010
 */
public class MonitorInstanceModel extends GenericModel<Dimension, Void, Object> {

    /** Connection data */
    private HashMap<String, String> connectionData;
    /** The Cloudwatch input data to tell the CloudWatch API what data we want */
    private CloudWatchInput cloudWatchInput;
    /** Logging tag */
    private static final String TAG = "org.elasticdroid.model.MonitorInstanceModel";

    /**
     * Constructor for type GenericActivity
     * @param activity
     */
    public MonitorInstanceModel(GenericActivity genericActivity, HashMap<String, String> connectionData,
            CloudWatchInput cloudWatchInput) {
        super(genericActivity);

        this.connectionData = connectionData;
        this.cloudWatchInput = cloudWatchInput;
    }

    /**
     * Another Constructor for type GenericListActivity
     * @param activity
     */
    public MonitorInstanceModel(GenericListActivity genericListActivity, HashMap<String, String> connectionData,
            CloudWatchInput cloudWatchInput) {
        super(genericListActivity);

        this.connectionData = connectionData;
        this.cloudWatchInput = cloudWatchInput;
    }

    /**
     * Execute metric retrieval in background
     */
    @Override
    protected Object doInBackground(Dimension... dimensions) {
        return retrieveMetrics(dimensions);
    }

    /** 
     * Perform the actual work of retrieving the metrics
     */
    public Object retrieveMetrics(Dimension... dimensions) {
        //the cloudwatch client to use
        AmazonCloudWatchClient cloudWatchClient = null;
        //the request to send to cloudwatch
        GetMetricStatisticsRequest request;
        //the metric stats result.
        GetMetricStatisticsResult result;

        //create credentials using the BasicAWSCredentials class
        BasicAWSCredentials credentials = new BasicAWSCredentials(connectionData.get("accessKey"),
                connectionData.get("secretAccessKey"));
        //create a cloudwatch client
        try {
            cloudWatchClient = new AmazonCloudWatchClient(credentials);
        } catch (AmazonServiceException amazonServiceException) {
            //if an error response is returned by AmazonIdentityManagement indicating either a 
            //problem with the data in the request, or a server side issue.
            Log.e(this.getClass().getName(), "Exception:" + amazonServiceException.getMessage());
            return amazonServiceException;
        } catch (AmazonClientException amazonClientException) {
            //If any internal errors are encountered inside the client while attempting to make 
            //the request or handle the response. For example if a network connection is not
            //available. 
            Log.e(this.getClass().getName(), "Exception:" + amazonClientException.getMessage());
            return amazonClientException;
        }

        //prepare request
        request = new GetMetricStatisticsRequest();
        request.setStartTime(new Date(cloudWatchInput.getStartTime()));
        request.setEndTime(new Date(cloudWatchInput.getEndTime()));
        request.setPeriod(cloudWatchInput.getPeriod());
        request.setMeasureName(cloudWatchInput.getMeasureName());
        request.setNamespace(cloudWatchInput.getNamespace());
        request.setStatistics(cloudWatchInput.getStatistics());
        request.setDimensions(Arrays.asList(dimensions));
        //tell the cloudwatch client where to look!
        cloudWatchClient.setEndpoint(AWSConstants.getCloudWatchEndpoint(cloudWatchInput.getRegion()));

        //get the monitoring result!
        try {
            result = cloudWatchClient.getMetricStatistics(request);
        } catch (AmazonServiceException amazonServiceException) {
            //if an error response is returned by AmazonIdentityManagement indicating either a 
            //problem with the data in the request, or a server side issue.
            Log.e(this.getClass().getName(), "Exception:" + amazonServiceException.getMessage());
            return amazonServiceException;
        } catch (AmazonClientException amazonClientException) {
            //If any internal errors are encountered inside the client while attempting to make 
            //the request or handle the response. For example if a network connection is not 
            //available. 
            Log.e(this.getClass().getName(), "Exception:" + amazonClientException.getMessage());
            return amazonClientException;
        }

        //get the data and print it out.
        List<Datapoint> data = result.getDatapoints();
        for (Datapoint datum : data) {
            Log.v(TAG, "Datum:" + datum.getAverage());
        }

        //sort the data in ascending order of timestamps
        Collections.sort(data, new CloudWatchDataSorter());

        //return the sorted data
        return data;
    }
}

class CloudWatchDataSorter implements Comparator<Datapoint> {

    /**
     * Sort two datapoint objects according to their timestamps.
     */
    @Override
    public int compare(Datapoint o1, Datapoint o2) {
        if (o1.getTimestamp().getTime() > o2.getTimestamp().getTime()) {
            return -1;
        } else if (o1.getTimestamp().getTime() == o2.getTimestamp().getTime()) {
            return 0;
        }

        return 1;
    }

}