vfma.LoadSensorData.java Source code

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Here is the source code for vfma.LoadSensorData.java

Source

package vfma;

import java.util.List;
import java.util.ArrayList;
//Copyright 2012-2015 Amazon.com, Inc. or its affiliates. All Rights Reserved.
//Licensed under the Apache License, Version 2.0.
import java.util.Iterator;

import com.amazonaws.services.dynamodbv2.AmazonDynamoDBClient;
import com.amazonaws.services.dynamodbv2.document.DynamoDB;
import com.amazonaws.services.dynamodbv2.document.Item;
import com.amazonaws.services.dynamodbv2.document.ItemCollection;
import com.amazonaws.services.dynamodbv2.document.ScanOutcome;
import com.amazonaws.services.dynamodbv2.document.Table;
import com.amazonaws.services.dynamodbv2.document.spec.ScanSpec;

import org.json.*;

public class LoadSensorData {

    public ArrayList<RawSensorData> getSensorData(String lastTimestamp) throws VFMException {

        ArrayList<RawSensorData> rsdlist = new ArrayList<RawSensorData>();

        try {

            AmazonDynamoDBClient client = new AmazonDynamoDBClient()
                    .withEndpoint("https://dynamodb.us-west-2.amazonaws.com");
            DynamoDB dynamoDB = new DynamoDB(client);
            Table table = dynamoDB.getTable("sensorData");
            ScanSpec scanSpec = new ScanSpec();

            System.out.println("Get sensors...");
            ItemCollection<ScanOutcome> items = table.scan(scanSpec);

            String lastTimeValue;

            Iterator<Item> iter = items.iterator();
            while (iter.hasNext()) {
                Item item = iter.next();

                RawSensorData rsd = new RawSensorData();

                rsd.setTimestamp(item.getJSON("pass").replace("\"", ""));
                final JSONObject rawData = new JSONObject(item.getJSON("payload"));
                rsd.setSensorId(rawData.getString("sensor_id_time"));
                rsd.setPassing(rawData.getString("passing"));

                System.out.println("Read " + rsd.getSensorId());

                if (rsd.getTimestamp().compareTo(lastTimestamp) > 0)
                    rsdlist.add(rsd);

                lastTimeValue = rsd.getTimestamp();
            }

        } catch (Exception e) {
            System.err.println("Unable to scan the table:");
            System.err.println(e.getMessage());
        }

        return rsdlist;
    }
}