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Java application

Here’s the sample Java application.


/**

* This sample Java application shows how to use the HCP HS3 API, which is

* compatible with Amazon S3. The application uses the Amazon S3 SDK.

*/

package com.hds.hcp.examples;


import java.io.File;

import java.io.FileInputStream; import java.io.FileOutputStream; import java.io.IOException;


import com.amazonaws.AmazonClientException; import com.amazonaws.AmazonServiceException; import com.amazonaws.ClientConfiguration; import com.amazonaws.Protocol;

import com.amazonaws.auth.BasicAWSCredentials; import com.amazonaws.services.s3.AmazonS3; import com.amazonaws.services.s3.AmazonS3Client;

import com.amazonaws.services.s3.model.AccessControlList; import com.amazonaws.services.s3.model.CanonicalGrantee; import com.amazonaws.services.s3.model.EmailAddressGrantee; import com.amazonaws.services.s3.model.GetObjectRequest; import com.amazonaws.services.s3.model.ListObjectsRequest; import com.amazonaws.services.s3.model.ObjectMetadata; import com.amazonaws.services.s3.model.Permission;

import com.amazonaws.services.s3.model.PutObjectRequest; import com.amazonaws.services.s3.model.Bucket;

import com.amazonaws.services.s3.model.PutObjectResult; import com.amazonaws.services.s3.model.S3Object;

import com.amazonaws.services.s3.model.ObjectListing; import com.amazonaws.services.s3.model.S3ObjectInputStream; import com.amazonaws.services.s3.model.S3ObjectSummary;


public class HS3SampleApp {


/**

* @param args

*/

public static void main(String[] args) {


/*

* Initialize access credentials for the HS3 client.

*/


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// base64 of HCP user name: "lgreen" String accessKey = "bGdyZWVu";

// md5 of HCP user password: "p4ssw0rd"

String secretKey = "2a9d119df47ff993b662a8ef36f9ea20";


/*

* Set up the client configuration to allow for 200 max HTTP

* connections, as this is an HCP best practice.

*/

ClientConfiguration myClientConfig = new ClientConfiguration(); myClientConfig.setMaxConnections(200);


/*

* Use the HTTP protocol to communicate with HCP. For you to use HTTPS,

* HCP may need to have a trusted SSL server certificate.

*/ myClientConfig.setProtocol(Protocol.HTTP);


/*

* Build the hs3Client to be used for communication with HCP.

*/

AmazonS3 hs3Client = new AmazonS3Client(

new BasicAWSCredentials(accessKey, secretKey), myClientConfig);


// Set up the service point to be the tenant in HCP. hs3Client.setEndpoint("europe.hcp.example.com");


/*

* Now that the hs3Client is created for HCP usage, proceed with some

* operations.

*/

String bucketName = "finance";


try {

/*

* Create a new bucket. With HCP, the bucket name does not need

* to be globally unique. It needs to be unique only within the HCP

* service point (that is, the HCP tenant).

*/

System.out.println("Creating bucket " + bucketName + "\n"); hs3Client.createBucket(bucketName);


/*

* List the buckets you own at the service point.

*/ System.out.println("Buckets:");

for (Bucket bucket : hs3Client.listBuckets()) { System.out.println(" * " + bucket.getName());

}

System.out.println();


/*


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* Add an ACL to the bucket to give read to a user with the

* specified user ID.

*/

AccessControlList bucketACL = hs3Client.getBucketAcl(bucketName); bucketACL.grantPermission(

new CanonicalGrantee("7370bb2d-033c-4f05-863e-35a4eaf1d739"), Permission.Read );

hs3Client.setBucketAcl(bucketName, bucketACL);


/*

* Upload a couple of objects to the bucket from files on the local file

* system.

*/

String objectNamePrefix = "quarterly_rpts/";


// Setup metadata for first object

String firstFileName = "input/Q4_2012.ppt"; ObjectMetadata metadata = new ObjectMetadata(); metadata.addUserMetadata("Author", "P.D. Gray"); metadata.addUserMetadata("Audit_Date", "2013-02-23");

// Content-Length must be set because the application will use an

// InputStream during the PUT. Otherwise, the whole file would be

// will be read into memory, which could cause the application to

// run out of memory.

metadata.setContentLength(new File(firstFileName).length());


System.out.println("Uploading first object to HCP from a file\n"); String firstObjectName = objectNamePrefix + "Q4_2012.ppt"; hs3Client.putObject(new PutObjectRequest(

bucketName, firstObjectName,

new FileInputStream(firstFileName), metadata));


// Write a second object without metadata. Also collect its ETag for

// later usage.

System.out.println("Uploading second object to HCP from a file\n"); String secondObjectName = objectNamePrefix + "Q3_2012.ppt"; PutObjectResult result = hs3Client.putObject(

new PutObjectRequest( bucketName, secondObjectName,

new File("input/Q3_2012.ppt"))); String secondObjectEtag = result.getETag();


/*

* List objects in the bucket with prefix quarterly_rpts/Q.

* The bucket listing is limited to 1,000 items per request.

* Be sure to check whether the returned listing has been

* truncated. If it has, retrieve additional results by using

* the AmazonS3.listNextBatchOfObjects(...) operation.

*/ System.out.println("Objects:");


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ObjectListing objectListing = hs3Client.listObjects(

new ListObjectsRequest()

.withBucketName(bucketName)

.withPrefix(objectNamePrefix

+ "Q"));

for (S3ObjectSummary objectSummary

: objectListing.getObjectSummaries()) { System.out.println(" * " + objectSummary.getKey() + " " +

"(size = " + objectSummary.getSize() + ")");

}

System.out.println();


/*

* Download an object. When you download an object, you get all

* the object metadata and a stream from which to read the object

* content.

*/

System.out.println("Downloading the first object\n");


S3Object firstObject = hs3Client.getObject(

new GetObjectRequest(bucketName,

firstObjectName));


// Write the content to a file named Q4_2012.ppt in the output folder. S3ObjectInputStream responseStream = firstObject.getObjectContent(); FileOutputStream dataFile = new FileOutputStream("output/Q4_2012.ppt");


// Keep reading bytes until the end of stream is reached. byte buffer[] = new byte[2048];

int readSize;

while (-1 != (readSize = responseStream.read(buffer))) { dataFile.write(buffer, 0, readSize);

}


dataFile.close();


/*

* Add an ACL to the first object to give full control to the user with

* the username rsilver. HCP will look up the user ID based on the

* username.

*/

AccessControlList objectACL = hs3Client.getObjectAcl(bucketName,

firstObjectName); objectACL.grantPermission(new EmailAddressGrantee("rsilver"),

Permission.FullControl); hs3Client.setObjectAcl(bucketName, firstObjectName, objectACL);


/*

* Perform a conditional download of object. This will get the object only

* if it doesn't match the ETag we received when storing the object.

*/

System.out.println("Checking the second object"); GetObjectRequest conditionalRequest


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= new GetObjectRequest(bucketName, secondObjectName)

.withNonmatchingETagConstraint(secondObjectEtag); S3Object conditionalObject = hs3Client.getObject(conditionalRequest); if (null == conditionalObject) {

System.out.println(" The object did not change; not downloaded.\n");

} else {

// The object has changed, download it to a new file.


System.out.println(

" The object changed; downloading new revision\n");


S3ObjectInputStream refreshResponseStream

= conditionalObject.getObjectContent(); FileOutputStream dataFile2

= new FileOutputStream("output/Q3_2012_Rev2.ppt");


// Keep reading bytes until the end of stream is reached. byte readBuffer[] = new byte[2048];

int conditionalReadSize;

while (-1 != (conditionalReadSize

= refreshResponseStream.read(readBuffer))) { dataFile2.write(readBuffer, 0, conditionalReadSize);

}

dataFile2.close();

}


/*

* Delete the objects.

*/ System.out.println(

"Deleting the objects created by this sample application\n"); hs3Client.deleteObject(bucketName, firstObjectName); hs3Client.deleteObject(bucketName, secondObjectName);


/*

* Delete the folder.

*/ System.out.println(

"Deleting the folder created when the first object was stored\n"); hs3Client.deleteObject(bucketName, objectNamePrefix);


/*

* Delete the bucket.

*/

System.out.println("Deleting the finance bucket\n"); hs3Client.deleteBucket(bucketName);


} catch (AmazonServiceException ase) { System.out.println(

"Caught an AmazonServiceException, which means the request made it "

+ "to HCP but was rejected for some reason."); System.out.println("Error Message: " + ase.getMessage()); System.out.println("HTTP Status Code: " + ase.getStatusCode());


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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 "

+ "HCP via HS3, such as not being able to access the network."); System.out.println("Error Message: " + ace.getMessage());

} catch (IOException ioe) { System.out.println(

"Caught an IOException while trying to create an object or read "

+ "from an internal buffer."); System.out.println("Error Message: " + ioe.getMessage());

}

}

}


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