DynamoDB.java Source code

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Here is the source code for DynamoDB.java

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/*
 * Copyright 2012-2016 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.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.GetItemRequest;
import com.amazonaws.services.dynamodbv2.model.GetItemResult;
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 DynamoDB {

    public static AmazonDynamoDBClient dynamoDB;
    public static String tableName = "SQS_TABLE";

    public DynamoDB(AmazonDynamoDBClient dynamoDB) {
        this.dynamoDB = dynamoDB;
    }

    public void createTable() throws InterruptedException {
        // Create table if it does not exist yet
        if (Tables.doesTableExist(dynamoDB, tableName)) {
            System.out.println("Table " + tableName + " is already ACTIVE");
        } else {
            // Create a table with a primary hash key named 'name', which holds a string
            CreateTableRequest createTableRequest = new CreateTableRequest().withTableName(tableName)
                    .withKeySchema(new KeySchemaElement().withAttributeName("Id").withKeyType(KeyType.HASH))
                    .withAttributeDefinitions(new AttributeDefinition().withAttributeName("Id")
                            .withAttributeType(ScalarAttributeType.S))
                    .withProvisionedThroughput(
                            new ProvisionedThroughput().withReadCapacityUnits(1L).withWriteCapacityUnits(1L));
            TableDescription createdTableDescription = dynamoDB.createTable(createTableRequest)
                    .getTableDescription();
            System.out.println("Created Table: " + createdTableDescription);

            // Wait for it to become active
            System.out.println("Waiting for " + tableName + " to become ACTIVE...");
            Tables.awaitTableToBecomeActive(dynamoDB, tableName);
        }

    }

    public void addItem(String msgID, String msg) {
        // Add an item           
        Map<String, AttributeValue> item = newItem(msgID, msg);
        PutItemRequest putItemRequest = new PutItemRequest(tableName, item);
        PutItemResult putItemResult = dynamoDB.putItem(putItemRequest);

    }

    private static Map<String, AttributeValue> newItem(String Id, String message) {
        Map<String, AttributeValue> item = new HashMap<String, AttributeValue>();
        //item.put("Id", new AttributeValue().withS(message));
        item.put("Id", new AttributeValue().withS(Id));
        item.put("message", new AttributeValue().withS(message));
        return item;
    }

    public boolean getItem(Map<String, AttributeValue> item, String id, String message) {
        //GetItemResult result = dynamoDB.getItem(tableName, item);       
        GetItemRequest getItemRequest = new GetItemRequest().withTableName(tableName).withKey(item);
        GetItemResult result = dynamoDB.getItem(getItemRequest);
        if (result.getItem() != null) {
            //addItem(id,message);
            System.out.println("item present");
            return true;
        }
        //System.out.println(result.getItem());
        else {
            return false;
        }
    }

}