aws.sample.AmazonDynamoDBSample.java Source code

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Here is the source code for aws.sample.AmazonDynamoDBSample.java

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package aws.sample;

/*
 * Copyright 2012 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 org.apache.http.conn.scheme.Scheme;

import net.ion.framework.util.Debug;

import com.amazonaws.AmazonClientException;
import com.amazonaws.AmazonServiceException;
import com.amazonaws.auth.AWSCredentials;
import com.amazonaws.auth.PropertiesCredentials;
import com.amazonaws.services.dynamodb.AmazonDynamoDBClient;
import com.amazonaws.services.dynamodb.model.AttributeValue;
import com.amazonaws.services.dynamodb.model.ComparisonOperator;
import com.amazonaws.services.dynamodb.model.Condition;
import com.amazonaws.services.dynamodb.model.CreateTableRequest;
import com.amazonaws.services.dynamodb.model.DeleteTableRequest;
import com.amazonaws.services.dynamodb.model.DescribeTableRequest;
import com.amazonaws.services.dynamodb.model.KeySchema;
import com.amazonaws.services.dynamodb.model.KeySchemaElement;
import com.amazonaws.services.dynamodb.model.ProvisionedThroughput;
import com.amazonaws.services.dynamodb.model.PutItemRequest;
import com.amazonaws.services.dynamodb.model.PutItemResult;
import com.amazonaws.services.dynamodb.model.ScanRequest;
import com.amazonaws.services.dynamodb.model.ScanResult;
import com.amazonaws.services.dynamodb.model.TableDescription;
import com.amazonaws.services.dynamodb.model.TableStatus;

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

    /*
     * Important: Be sure to fill in your AWS access credentials in the AwsCredentials.properties file before you try to run this sample. http://aws.amazon.com/security-credentials
     */

    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.PropertiesCredentials
     * @see com.amazonaws.ClientConfiguration
     */
    private static void init() throws Exception {
        System.setProperty("com.amazonaws.sdk.disableCertChecking", "true");

        AWSCredentials credentials = new PropertiesCredentials(
                AmazonDynamoDBSample.class.getResourceAsStream("/AwsCredentials.properties"));
        Debug.line(credentials.getAWSAccessKeyId(), credentials.getAWSSecretKey());
        dynamoDB = new AmazonDynamoDBClient(credentials);

    }

    public static void main(String[] args) throws Exception {
        init();

        try {
            String tableName = "my-favorite-movies-table";

            // Create a table with a primary key named 'name', which holds a string
            CreateTableRequest createTableRequest = new CreateTableRequest().withTableName(tableName)
                    .withKeySchema(
                            new KeySchema(new KeySchemaElement().withAttributeName("name").withAttributeType("S")))
                    .withProvisionedThroughput(
                            new ProvisionedThroughput().withReadCapacityUnits(10L).withWriteCapacityUnits(10L));
            TableDescription createdTableDescription = dynamoDB.createTable(createTableRequest)
                    .getTableDescription();
            System.out.println("Created Table: " + createdTableDescription);

            // Wait for it to become active
            waitForTableToBecomeAvailable(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);

            DeleteTableRequest deleteTableRequest = new DeleteTableRequest(tableName);
            dynamoDB.deleteTable(deleteTableRequest);
            System.out.println("Delete Table: ");

        } 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) {
            ace.printStackTrace();
            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;
    }

    private static void waitForTableToBecomeAvailable(String tableName) {
        System.out.println("Waiting for " + tableName + " to become ACTIVE...");

        long startTime = System.currentTimeMillis();
        long endTime = startTime + (10 * 60 * 1000);
        while (System.currentTimeMillis() < endTime) {
            try {
                Thread.sleep(1000 * 4);
            } catch (Exception e) {
            }
            try {
                DescribeTableRequest request = new DescribeTableRequest().withTableName(tableName);
                TableDescription tableDescription = dynamoDB.describeTable(request).getTable();
                String tableStatus = tableDescription.getTableStatus();
                System.out.println("  - current state: " + tableStatus);
                if (tableStatus.equals(TableStatus.ACTIVE.toString()))
                    return;
            } catch (AmazonServiceException ase) {
                if (ase.getErrorCode().equalsIgnoreCase("ResourceNotFoundException") == false)
                    throw ase;
            }
        }

        throw new RuntimeException("Table " + tableName + " never went active");
    }

}