DynamoDBManager.java

package com.hipermediasoft.manager;

import com.amazonaws.ClientConfiguration;
import com.amazonaws.auth.AWSCredentialsProvider;
import com.amazonaws.auth.ClasspathPropertiesFileCredentialsProvider;
import com.amazonaws.regions.Regions;
import com.amazonaws.services.dynamodbv2.AmazonDynamoDBClient;
import com.amazonaws.services.dynamodbv2.datamodeling.DynamoDBMapper;

public class DynamoDBManager {

	private DynamoDBMapper mapper;
	private static volatile DynamoDBManager instance;
	public static final String DYNAMODB_ENDPOINT = System.getenv("DYNAMODB_ENDPOINT");
	public DynamoDBManager(){
		ClientConfiguration clientConfiguration = new ClientConfiguration()
					.withMaxErrorRetry(5);
		AmazonDynamoDBClient client = new AmazonDynamoDBClient(clientConfiguration);
		client.configureRegion(Regions.fromName(System.getenv("REGION")));
		client.withEndpoint(DynamoDBManager.DYNAMODB_ENDPOINT);
		
    		//Usar solo en caso de que necesiten asociar algun item a una URL de S3 con la clase helper S3Link
		AWSCredentialsProvider s3CredentialProvider = new ClasspathPropertiesFileCredentialsProvider();
		mapper = new DynamoDBMapper(client, s3CredentialProvider);
	}
	
	public static DynamoDBManager instance(){
		if (instance == null) {
            synchronized(DynamoDBManager.class) {
                if (instance == null)
                    instance = new DynamoDBManager();
            }
        }
        return instance;
	}
	
	public static DynamoDBMapper mapper() {

        DynamoDBManager manager = instance();
        return manager.mapper;
    }
}