com.hussi.aws.dynamoDB.AmazonDynamoDBSample.java Source code

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Here is the source code for com.hussi.aws.dynamoDB.AmazonDynamoDBSample.java

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package com.hussi.aws.dynamoDB;

/*
 * Copyright 2012-2017 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.HashMap;
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.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.TableUtils;

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

    /*
     * 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
     *      (~/.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;

    /**
     * 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
         * (~/.aws/credentials).
         */
        AWSCredentials credentials = null;
        try {
            credentials = new ProfileCredentialsProvider().getCredentials();
            System.out.println("credentials.getAWSAccessKeyId()===>>>" + credentials.getAWSAccessKeyId());
            System.out.println("credentials.getAWSSecretKey()===>>>" + credentials.getAWSSecretKey());
            //System.exi   t(0);

        } 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 (~/.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 {
            String tableName = "hussi_first_dynamo_table";

            // Create a table with a primary hash key named 'name', which holds a string
            CreateTableRequest createTableRequest = new CreateTableRequest().withTableName(tableName)
                    .withKeySchema(new KeySchemaElement().withAttributeName("name").withKeyType(KeyType.HASH))
                    .withAttributeDefinitions(new AttributeDefinition().withAttributeName("name")
                            .withAttributeType(ScalarAttributeType.S))
                    .withProvisionedThroughput(
                            new ProvisionedThroughput().withReadCapacityUnits(1L).withWriteCapacityUnits(1L));

            // Create table if it does not exist yet
            TableUtils.createTableIfNotExists(dynamoDB, createTableRequest);
            // wait for the table to move into ACTIVE state
            TableUtils.waitUntilActive(dynamoDB, tableName);

            // Describe our new table
            DescribeTableRequest describeTableRequest = new DescribeTableRequest().withTableName(tableName);
            TableDescription tableDescription = dynamoDB.describeTable(describeTableRequest).getTable();
            System.out.println("Table Description: " + tableDescription);

            // Add an item
            Map<String, AttributeValue> item = newItem("Bill & Ted's Excellent Adventure", 1989, "****", "James",
                    "Sara");
            PutItemRequest putItemRequest = new PutItemRequest(tableName, item);
            PutItemResult putItemResult = dynamoDB.putItem(putItemRequest);
            System.out.println("Result: " + putItemResult);

            // Add another item
            item = newItem("Airplane", 1980, "*****", "James", "Billy Bob");
            putItemRequest = new PutItemRequest(tableName, item);
            putItemResult = dynamoDB.putItem(putItemRequest);
            System.out.println("Result: " + putItemResult);

            // Scan items for movies with a year attribute greater than 1985
            HashMap<String, Condition> scanFilter = new HashMap<String, Condition>();
            Condition condition = new Condition().withComparisonOperator(ComparisonOperator.GT.toString())
                    .withAttributeValueList(new AttributeValue().withN("1985"));
            scanFilter.put("year", condition);
            ScanRequest scanRequest = new ScanRequest(tableName).withScanFilter(scanFilter);
            ScanResult scanResult = dynamoDB.scan(scanRequest);
            System.out.println("Result: " + scanResult);

        } 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(String name, int year, String rating, String... fans) {
        Map<String, AttributeValue> item = new HashMap<String, AttributeValue>();
        item.put("name", new AttributeValue(name));
        item.put("year", new AttributeValue().withN(Integer.toString(year)));
        item.put("rating", new AttributeValue(rating));
        item.put("fans", new AttributeValue().withSS(fans));

        return item;
    }

}