NYSEQuery.java Source code

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Here is the source code for NYSEQuery.java

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/*
 * Copyright 2012-2015 Amazon.com, Inc. or its affiliates. All Rights Reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License").
 * You may not use this file except in compliance with the License.
 * A copy of the License is located at
 *
 *  http://aws.amazon.com/apache2.0
 *
 * or in the "license" file accompanying this file. This file 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.
 */
import java.io.BufferedReader;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.IOException;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;

import com.amazonaws.AmazonClientException;
import com.amazonaws.AmazonServiceException;
import com.amazonaws.auth.AWSCredentials;
import com.amazonaws.auth.profile.ProfileCredentialsProvider;
import com.amazonaws.regions.Region;
import com.amazonaws.regions.Regions;
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.QueryOutcome;
import com.amazonaws.services.dynamodbv2.document.Table;
import com.amazonaws.services.dynamodbv2.document.spec.QuerySpec;
import com.amazonaws.services.dynamodbv2.document.utils.ValueMap;
import com.amazonaws.services.dynamodbv2.model.AttributeValue;
import com.amazonaws.services.dynamodbv2.model.PutItemRequest;
import com.amazonaws.services.dynamodbv2.util.Tables;

/**
 * This sample demonstrates how to perform a few simple operations with the
 * Amazon DynamoDB service.
 */
public class NYSEQuery {

    /*
     * Before running the code: Fill in your AWS access credentials in the
     * provided credentials file template, and be sure to move the file to the
     * default location (/Users/usdgadiraj/.aws/credentials) where the sample
     * code will load the credentials from.
     * https://console.aws.amazon.com/iam/home?#security_credential
     *
     * WARNING: To avoid accidental leakage of your credentials, DO NOT keep the
     * credentials file in your source directory.
     */

    static AmazonDynamoDBClient dynamoDB;
    static DynamoDB dynamo;
    static NyseParser nyseParser = new NyseParser();

    /**
     * The only information needed to create a client are security credentials
     * consisting of the AWS Access Key ID and Secret Access Key. All other
     * configuration, such as the service endpoints, are performed
     * automatically. Client parameters, such as proxies, can be specified in an
     * optional ClientConfiguration object when constructing a client.
     *
     * @see com.amazonaws.auth.BasicAWSCredentials
     * @see com.amazonaws.auth.ProfilesConfigFile
     * @see com.amazonaws.ClientConfiguration
     */
    private static void init() throws Exception {
        /*
         * The ProfileCredentialsProvider will return your [default] credential
         * profile by reading from the credentials file located at
         * (/Users/usdgadiraj/.aws/credentials).
         */
        AWSCredentials credentials = null;
        try {
            credentials = new ProfileCredentialsProvider("default").getCredentials();
        } catch (Exception e) {
            throw new AmazonClientException("Cannot load the credentials from the credential profiles file. "
                    + "Please make sure that your credentials file is at the correct "
                    + "location (/Users/usdgadiraj/.aws/credentials), and is in valid format.", e);
        }
        dynamoDB = new AmazonDynamoDBClient(credentials);
        Region region = Region.getRegion(Regions.US_EAST_1);
        dynamoDB.setRegion(region);
        dynamoDB.setEndpoint("http://dynamo.itversity.com:8000");
        dynamo = new DynamoDB(dynamoDB);
    }

    public static void main(String[] args) throws Exception {
        init();
        String tableName = "stock_eod";
        query(tableName);
    }

    private static void query(String tableName) {
        Table table = null;
        try {
            // Create table if it does not exist yet
            if (!Tables.doesTableExist(dynamoDB, tableName)) {
                System.out.println("Table " + tableName + " is does not exist");
            } else {
                table = dynamo.getTable(tableName);
            }

            // http://docs.aws.amazon.com/amazondynamodb/latest/developerguide/Expressions.SpecifyingConditions.html
            // select stockTicker, tradeDate, v from stock_eod 
            // where stockTicker = 'LEA' and tradeDate between '02-Oct-2013' and '03-Oct-2013'
            QuerySpec spec = new QuerySpec().withProjectionExpression("stockTicker,tradeDate,v")
                    .withKeyConditionExpression("stockTicker = :v_st and tradeDate between :v_sd and :v_ed")
                    //               .withFilterExpression("contains(tradeDate, :v_t)")
                    .withValueMap(new ValueMap().withString(":v_st", "LEA").withString(":v_sd", "02-Oct-2013")
                            .withString(":v_ed", "03-Oct-2013")
                    // .withString(":v_td", "01-Oct-2013")
                    //                     .withString(":v_t", "Oct")
                    ).withConsistentRead(true);

            ItemCollection<QueryOutcome> items = table.query(spec);

            Iterator<Item> iterator = items.iterator();
            while (iterator.hasNext()) {
                System.out.println(iterator.next().toJSONPretty());
            }

        } catch (AmazonServiceException ase) {
            System.out.println("Caught an AmazonServiceException, which means your request made it "
                    + "to AWS, but was rejected with an error response for some reason.");
            System.out.println("Error Message:    " + ase.getMessage());
            System.out.println("HTTP Status Code: " + ase.getStatusCode());
            System.out.println("AWS Error Code:   " + ase.getErrorCode());
            System.out.println("Error Type:       " + ase.getErrorType());
            System.out.println("Request ID:       " + ase.getRequestId());
        } catch (AmazonClientException ace) {
            System.out.println("Caught an AmazonClientException, which means the client encountered "
                    + "a serious internal problem while trying to communicate with AWS, "
                    + "such as not being able to access the network.");
            System.out.println("Error Message: " + ace.getMessage());
        }
    }

    private static Map<String, AttributeValue> newItem(NyseParser nyseParser) {
        Map<String, AttributeValue> item = new HashMap<String, AttributeValue>();
        item.put("stockTicker", new AttributeValue(nyseParser.getStockTicker()));
        item.put("tradeDate", new AttributeValue(nyseParser.getTransactionDate()));
        item.put("lp", new AttributeValue().withN(Float.toString(nyseParser.getLowPrice())));
        item.put("op", new AttributeValue().withN(Float.toString(nyseParser.getOpenPrice())));
        item.put("cp", new AttributeValue().withN(Float.toString(nyseParser.getClosePrice())));
        item.put("hp", new AttributeValue().withN(Float.toString(nyseParser.getHighPrice())));
        item.put("v", new AttributeValue().withN(Float.toString(nyseParser.getVolume())));

        return item;
    }

}