Java tutorial
/* * Copyright 2012-2014 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.util.Arrays; import java.util.Date; import java.util.HashMap; import java.util.Map; import java.util.Random; 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.model.AttributeDefinition; import com.amazonaws.services.dynamodbv2.model.AttributeValue; import com.amazonaws.services.dynamodbv2.model.ComparisonOperator; import com.amazonaws.services.dynamodbv2.model.Condition; import com.amazonaws.services.dynamodbv2.model.CreateTableRequest; import com.amazonaws.services.dynamodbv2.model.DescribeTableRequest; import com.amazonaws.services.dynamodbv2.model.KeySchemaElement; import com.amazonaws.services.dynamodbv2.model.KeyType; import com.amazonaws.services.dynamodbv2.model.ProvisionedThroughput; import com.amazonaws.services.dynamodbv2.model.PutItemRequest; import com.amazonaws.services.dynamodbv2.model.PutItemResult; import com.amazonaws.services.dynamodbv2.model.ScalarAttributeType; import com.amazonaws.services.dynamodbv2.model.ScanRequest; import com.amazonaws.services.dynamodbv2.model.ScanResult; import com.amazonaws.services.dynamodbv2.model.TableDescription; import com.amazonaws.services.dynamodbv2.util.Tables; /** * This sample demonstrates how to perform a few simple operations with the * Amazon DynamoDB service. */ public class RandomQuery2OnDynamoDB { /* * WANRNING: To avoid accidental leakage of your credentials, DO NOT keep * the credentials file in your source directory. */ static AmazonDynamoDBClient dynamoDB; static AmazonDynamoDBClient client = new AmazonDynamoDBClient(new ProfileCredentialsProvider()); static String tableName = "weather-100k"; /** * 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 * (C:\\Users\\Divendar\\.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 (C:\\Users\\Divendar\\.aws\\credentials), and is in valid format.", e); } dynamoDB = new AmazonDynamoDBClient(credentials); Region usWest2 = Region.getRegion(Regions.US_WEST_2); dynamoDB.setRegion(usWest2); } public static void main(String[] args) throws Exception { init(); try { // Describe our new table DescribeTableRequest describeTableRequest = new DescribeTableRequest().withTableName(tableName); TableDescription tableDescription = dynamoDB.describeTable(describeTableRequest).getTable(); System.out.println("Table Description: " + tableDescription); long lStartTime = new Date().getTime(); System.out.println("start time: " + lStartTime); Random rn = new Random(); Long lItem = tableDescription.getItemCount(); int iNoOfItems = lItem.intValue(); int iPointOnePercent = (int) ((int) iNoOfItems * 0.001); int iOnePercent = (int) ((int) iNoOfItems * 0.01); System.out.println("TotalItems:" + iNoOfItems + "::0.1% of data is :: " + iPointOnePercent + "::1% of data is :" + iOnePercent); // Generating 25000 random queries for 0.1 to 1 % of the data for (int i = 0; i <= 24999; i++) { String randomInt = Integer.toString(rn.nextInt(iOnePercent - iPointOnePercent) + iPointOnePercent); HashMap<String, Condition> scanFilter = new HashMap<String, Condition>(); Condition condition = new Condition().withComparisonOperator(ComparisonOperator.EQ.toString()) .withAttributeValueList(new AttributeValue().withN(randomInt)); scanFilter.put("id", condition); ScanRequest scanRequest = new ScanRequest(tableName).withScanFilter(scanFilter); ScanResult scanResult = dynamoDB.scan(scanRequest); System.out.println("Random No :" + randomInt + ":: Query no: " + (i + 1)); } // calculate time difference for update file time long lEndTime = new Date().getTime(); long difference = lEndTime - lStartTime; System.out.println("Elapsed milliseconds: " + difference); System.out.println("Elapsed seconds: " + difference * 0.001); System.out.println("Elapsed Minutes: " + (int) ((difference / (1000 * 60)) % 60)); } 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()); } } }