How to change metadata on an object in Amazon S3

Question

If you have already uploaded an object to an Amazon S3 bucket, how do you change the metadata using the API? It is possible to do this in the AWS Management Console, but it

Answer 1

In Java, You can copy object to the same location. Here metadata will not copy while copying an Object. You have to get metadata of original and set to copy request. This method is more recommended to insert or update metadata of an Amazon S3 object

ObjectMetadata metadata = amazonS3Client.getObjectMetadata(bucketName, fileKey);
ObjectMetadata metadataCopy = new ObjectMetadata();
metadataCopy.addUserMetadata("yourKey", "updateValue");
metadataCopy.addUserMetadata("otherKey", "newValue");
metadataCopy.addUserMetadata("existingKey", metadata.getUserMetaDataOf("existingValue"));

CopyObjectRequest request = new CopyObjectRequest(bucketName, fileKey, bucketName, fileKey)
      .withSourceBucketName(bucketName)
      .withSourceKey(fileKey)
      .withNewObjectMetadata(metadataCopy);

amazonS3Client.copyObject(request);