确定对象的内容类型。

    public static void getContentType (S3Client s3, String bucketName, String keyName) {
        try {
            HeadObjectRequest objectRequest = HeadObjectRequest.builder()
                .key(keyName)
                .bucket(bucketName)
                .build();
            HeadObjectResponse objectHead = s3.headObject(objectRequest);
            String type = objectHead.contentType();
            System.out.println("The object content type is "+type);
        } catch (S3Exception e) {
            System.err.println(e.awsErrorDetails().errorMessage());
            System.exit(1);
                
获取对象的还原状态。
                
    public static void checkStatus(S3Client s3, String bucketName, String keyName) {
        try {
            HeadObjectRequest headObjectRequest = HeadObjectRequest.builder()
                .bucket(bucketName)
                .key(keyName)
                .build();
            HeadObjectResponse response = s3.headObject(headObjectRequest);
            System.out.println("The Amazon S3 object restoration status is "+response.restore());
        } catch (S3Exception e) {
            System.err.println(e.awsErrorDetails().errorMessage());
            System.exit(1);
  # @param object [Aws::S3::Object] An Amazon S3 object.
  def initialize(object)
    @object = object
  # Checks whether the object exists.
  # @return [Boolean] True if the object exists; otherwise false.
  def exists?
    @object.exists?
  rescue Aws::Errors::ServiceError => e
    puts "Couldn't check existence of object #{@object.bucket.name}:#{@object.key}. Here's why: #{e.message}"
    false
# Replace bucket name and object key with an existing bucket and object that you own.
def run_demo
  bucket_name = "doc-example-bucket"
  object_key = "my-object.txt"
  wrapper = ObjectExistsWrapper.new(Aws::S3::Object.new(bucket_name, object_key))
  exists = wrapper.exists?
  puts "Object #{object_key} #{exists ? 'does' : 'does not'} exist."
run_demo if $PROGRAM_NAME == __FILE__