ECS 3.6.2 Data Access Guide

Using the Java Amazon SDK

You can access ECS object storage using the Java S3 SDK.

By default the AmazonS3Client client object is coded to work directly against amazon.com. This section shows how to set up the AmazonS3Client to work against ECS.

In order to create an instance of the AmazonS3Client object, you need to pass it credentials. This is achieved through creating an AWSCredentials object and passing it the AWS Access Key (your ECS username) and your generated secret key for ECS.

The following code snippet shows how to set this up.

AmazonS3Client client = new AmazonS3Client(new BasicAWSCredentials(uid, secret));

By default the Amazon client attempts to contact Amazon WebServices. In order to override this behavior and contact ECS you need to set a specific endpoint.

You can set the endpoint using the setEndpoint method. The protocol specified on the endpoint dictates whether the client should be directed at the HTTP port (9020) or the HTTPS port (9021).

In the snippet below, the client is being used to access ECS over HTTP:

AmazonS3Client client = new AmazonS3Client(new BasicAWSCredentials(uid, secret));
client.setEndpoint("http://ecs1.emc.com:9020");

When using path-style addressing ( ecs1.emc.com/mybucket ), you will need to set the setPathStyleAccess option, as shown below:

S3ClientOptions options = new S3ClientOptions();
options.setPathStyleAccess(true);

AmazonS3Client client = new AmazonS3Client(new BasicAWSCredentials(uid, secret));
client.setEndpoint("http://ecs1.emc.com:9020");
client.setS3ClientOptions(options);

The following code shows how to list objects in a bucket.

ObjectListing objects = client.listObjects("mybucket");
for (S3ObjectSummary summary : objects.getObjectSummaries()) {
    System.out.println(summary.getKey()+ "   "+summary.getOwner());
}

The CreateBucket operation differs from other operations in that it expects a region to be specified. Against S3 this would indicate the data center in which the bucket should be created. However, ECS does not support regions. For this reason, when calling the CreateBucket operation, we specify the standard region, which stops the AWS client from downloading the Amazon Region configuration file from Amazon CloudFront.

client.createBucket("mybucket", "Standard");

The complete example for communicating with the ECS S3 data service, creating a bucket, and then manipulating an object is provided below:

public class Test {
    public static String uid = "root";
    public static String secret = "KHBkaH0Xd7YKF43ZPFbWMBT9OP0vIcFAMkD/9dwj";
    public static String viprDataNode = "http://ecs.yourco.com:9020";

    public static String bucketName = "myBucket";
    public static File objectFile = new File("/photos/cat1.jpg");

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

        AmazonS3Client client = new AmazonS3Client(new BasicAWSCredentials(uid, secret));

        S3ClientOptions options = new S3ClientOptions();
        options.setPathStyleAccess(true);

        AmazonS3Client client = new AmazonS3Client(credentials);
        client.setEndpoint(viprDataNode);
        client.setS3ClientOptions(options);

        client.createBucket(bucketName, "Standard");
        listObjects(client);

        client.putObject(bucketName, objectFile.getName(), objectFile);
        listObjects(client);

        client.copyObject(bucketName,objectFile.getName(),bucketName, "copy-" + objectFile.getName());
        listObjects(client);
    }

    public static void listObjects(AmazonS3Client client) {
        ObjectListing objects = client.listObjects(bucketName);
        for (S3ObjectSummary summary : objects.getObjectSummaries()) {
            System.out.println(summary.getKey()+ "   "+summary.getOwner());
        }
    }
}