Question

public class downloads3 {
    private static String bucketName = "s3-upload-sdk-sample-akiaj6ufcgzvw7yukypa";
    **private static String key        = "__________________________________";**

    public static void main(String[] args) throws IOException {
        AmazonS3 s3Client = new AmazonS3Client(new PropertiesCredentials(
                downloads3.class.getResourceAsStream(
                        "AwsCredentials.properties")));
        try {
            System.out.println("Downloading an object");
            S3Object s3object = s3Client.getObject(new GetObjectRequest(
                    bucketName, key));
            System.out.println("Content-Type: "  + 
                    s3object.getObjectMetadata().getContentType());
            displayTextInputStream(s3object.getObjectContent());

           // Get a range of bytes from an object.

            GetObjectRequest rangeObjectRequest = new GetObjectRequest(
                    bucketName, key);
            rangeObjectRequest.setRange(0, 10);
            S3Object objectPortion = s3Client.getObject(rangeObjectRequest);

            System.out.println("Printing bytes retrieved.");
            displayTextInputStream(objectPortion.getObjectContent());

        } catch (AmazonServiceException ase) {
            System.out.println("Caught an AmazonServiceException, which" +
                    " means your request made it " +
                    "to Amazon S3, but was rejected with an error response" +
                    " for some reason.");
            System.out.println("Error Message:    " + ase.getMessage());
            System.out.println("HTTP Status Code: " + ase.getStatusCode());
            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 " +
                    "an internal error while trying to " +
                    "communicate with S3, " +
                    "such as not being able to access the network.");
            System.out.println("Error Message: " + ace.getMessage());
        }
    }

    private static void displayTextInputStream(InputStream input)
    throws IOException {
        // Read one text line at a time and display.
        BufferedReader reader = new BufferedReader(new 
                InputStreamReader(input));
        while (true) {
            String line = reader.readLine();
            if (line == null) break;

            System.out.println("    " + line);
        }
        System.out.println();
    }
}

我正在尝试使用Java从Amazon S3存储桶下载对象。但它似乎不起作用，并一直给我下面显示的错误。输入的正确键是什么？访问密钥或密钥？

Downloading an object
Caught an AmazonServiceException, which means your request made it to Amazon S3, but was rejected with an error response for some reason.
Error Message:    The specified key does not exist.
HTTP Status Code: 404
AWS Error Code:   NoSuchKey
Error Type:       Client
Request ID:       F9548FC068DB1646

Answer 1

确保您在代码中使用的密钥与存储桶中的密钥相同。请记住，Amazon S3密钥不区分大小写，这意味着您的密钥名称可能有一些不同的情况，例如大写或小写。

检查并重试。

Answer 2

正如其他人指出密钥是存储在S3上的对象（文件/文件夹等）的唯一标识符。

有关术语和概念设计的更多信息，请参阅http://docs.aws.amazon.com/AmazonS3/latest/dev/Introduction.html#CoreConcepts。

注意：如果您尝试上传文件然后立即执行getObjectRequest，有时（大多数情况下）会出现延迟并导致404 NoSuchKey，因此您需要考虑你设计中的场景。

A＆＃39; key＆＃39;是不用于请求的凭据。如果是这种情况，您将获得 401 Unauthorized 。 404表示已设置适当的身份验证凭据。

密钥可以被视为文件名（或者就此而言的文件名）。这可以是任意值，但大多数人更喜欢使用正斜杠模拟文件系统结构（甚至亚马逊S3控制台都这样做，并且有创建文件夹按钮等。）

如果您可以访问控制台，请浏览您的存储桶并确保所有关键字前缀或“父目录”。存在，包括存储桶或＆＃39;根文件夹＆＃39;。

Answer 3

Amazon S3存储桶中的“密钥”是您要下载的文件名。

在你的情况下：

private static String key        = "__________________________________"; //will be file name/ file path to that file in Amazon Bucket.

Answer 4

我遇到了类似的问题。我的访问密钥，密钥，存储桶，端点和路径都是正确的。

事实证明，对我来说问题是我在S3中指向的文件不存在因此404错误。

使用Java在Amazon S3中下载存储桶的密钥

4 个答案: