ModifyACLExistingObject.java

// Copyright 2018 Amazon.com, Inc. or its affiliates. All Rights Reserved.
// SPDX-License-Identifier: MIT-0 (For details, see https://github.com/awsdocs/amazon-s3-developer-guide/blob/master/LICENSE-SAMPLECODE.)

import java.io.IOException;

import com.amazonaws.AmazonServiceException;
import com.amazonaws.SdkClientException;
import com.amazonaws.auth.profile.ProfileCredentialsProvider;
import com.amazonaws.services.s3.AmazonS3;
import com.amazonaws.services.s3.AmazonS3ClientBuilder;
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.Permission;

public class ModifyACLExistingObject {

    public static void main(String[] args) throws IOException {
        String clientRegion = "*** Client region ***";
        String bucketName = "*** Bucket name ***";
        String keyName = "*** Key name ***";
        String emailGrantee = "*** [email protected] ***";

        try {
            AmazonS3 s3Client = AmazonS3ClientBuilder.standard()
                    .withCredentials(new ProfileCredentialsProvider())
                    .withRegion(clientRegion)
                    .build();

            // Get the existing object ACL that we want to modify.
            AccessControlList acl = s3Client.getObjectAcl(bucketName, keyName);
            
            // Clear the existing list of grants.
            acl.getGrantsAsList().clear();
            
            // Grant a sample set of permissions, using the existing ACL owner for Full Control permissions.
            acl.grantPermission(new CanonicalGrantee(acl.getOwner().getId()), Permission.FullControl);
            acl.grantPermission(new EmailAddressGrantee(emailGrantee), Permission.WriteAcp);
    
            // Save the modified ACL back to the object.
            s3Client.setObjectAcl(bucketName, keyName, acl);
        }
        catch(AmazonServiceException e) {
            // The call was transmitted successfully, but Amazon S3 couldn't process 
            // it, so it returned an error response.
            e.printStackTrace();
        }
        catch(SdkClientException e) {
            // Amazon S3 couldn't be contacted for a response, or the client
            // couldn't parse the response from Amazon S3.
            e.printStackTrace();
        }
    }
}