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Use HeadObject with an AWS SDK

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The following code example shows how to use HeadObject.

Java

SDK for Java 2.x

Note

There's more on GitHub. Find the complete example and learn how to set up and run in the AWS Code Examples Repository.

Get metadata of an object in a directory bucket.

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import software.amazon.awssdk.regions.Region;
import software.amazon.awssdk.services.s3.S3Client;
import software.amazon.awssdk.services.s3.model.HeadObjectRequest;
import software.amazon.awssdk.services.s3.model.HeadObjectResponse;
import software.amazon.awssdk.services.s3.model.S3Exception;

import java.nio.file.Path;

import static com.example.s3.util.S3DirectoryBucketUtils.createDirectoryBucket;
import static com.example.s3.util.S3DirectoryBucketUtils.createS3Client;
import static com.example.s3.util.S3DirectoryBucketUtils.deleteAllObjectsInDirectoryBucket;
import static com.example.s3.util.S3DirectoryBucketUtils.deleteDirectoryBucket;
import static com.example.s3.util.S3DirectoryBucketUtils.getFilePath;
import static com.example.s3.util.S3DirectoryBucketUtils.putDirectoryBucketObject;

    /**
     * Retrieves metadata for an object in the specified S3 directory bucket.
     *
     * @param s3Client   The S3 client used to interact with S3
     * @param bucketName The name of the directory bucket
     * @param objectKey  The key (name) of the object to retrieve metadata for
     * @return True if the object exists, false otherwise
     */
    public static boolean headDirectoryBucketObject(S3Client s3Client, String bucketName, String objectKey) {
        logger.info("Retrieving metadata for object: {} from bucket: {}", objectKey, bucketName);

        try {
            // Create a HeadObjectRequest
            HeadObjectRequest headObjectRequest = HeadObjectRequest.builder()
                    .bucket(bucketName)
                    .key(objectKey)
                    .build();

            // Retrieve the object metadata
            HeadObjectResponse response = s3Client.headObject(headObjectRequest);
            logger.info("Amazon S3 object: \"{}\" found in bucket: \"{}\" with ETag: \"{}\"", objectKey, bucketName,
                    response.eTag());
            logger.info("Content-Type: {}", response.contentType());
            logger.info("Content-Length: {}", response.contentLength());
            logger.info("Last Modified: {}", response.lastModified());
            return true;

        } catch (S3Exception e) {
            logger.error("Failed to retrieve object metadata: {} - Error code: {}", e.awsErrorDetails().errorMessage(),
                    e.awsErrorDetails().errorCode(), e);
            return false;
        }
    }

• For API details, see HeadObject in AWS SDK for Java 2.x API Reference.

For a complete list of AWS SDK developer guides and code examples, see Developing with Amazon S3 using the AWS SDKs. This topic also includes information about getting started and details about previous SDK versions.