Package org.jets3t.service.utils
Class ServiceUtils
- java.lang.Object
-
- org.jets3t.service.utils.ServiceUtils
-
public class ServiceUtils extends Object
General utility methods used throughout the jets3t project.- Author:
- James Murty
-
-
Constructor Summary
Constructors Constructor Description ServiceUtils()
-
Method Summary
All Methods Static Methods Concrete Methods Modifier and Type Method Description static S3Object
buildObjectFromUrl(String host, String urlPath, String s3Endpoint)
Builds an object based on the bucket name and object key information available in the components of a URL.static Map<String,Object>
cleanRestMetadataMap(Map<String,Object> metadata, String headerPrefix, String metadataPrefix)
From a map of metadata returned from a REST GET or HEAD request, returns a map of metadata with the HTTP-connection-specific metadata items removed.static byte[]
computeMD5Hash(byte[] data)
Computes the MD5 hash of the given data and returns it as a hex string.static byte[]
computeMD5Hash(InputStream is)
Computes the MD5 hash of the data in the given input stream and returns it as a hex string.static long
countBytesInObjects(S3Object[] objects)
Counts the total number of bytes in a set of S3Objects by summing the content length of each.static String
findBucketNameInHostname(String host, String s3Endpoint)
Identifies the name of a bucket from a given host name, if available.static String
formatIso8601Date(Date date)
static String
formatRfc822Date(Date date)
static byte[]
fromBase64(String b64Data)
Converts a Base64-encoded string to the original byte data.static byte[]
fromHex(String hexData)
Converts a Hex-encoded data string to the original byte data.static String
generateS3HostnameForBucket(String bucketName, boolean isDnsBucketNamingDisabled, String s3Endpoint)
static String
getUserAgentDescription(String applicationDescription)
Returns a user agent string describing the jets3t library, and optionally the application using it, to server-side services.static boolean
isBucketNameValidDNSName(String bucketName)
Returns true if the given bucket name can be used as a component of a valid DNS name.static boolean
isEtagAlsoAnMD5Hash(String etag)
Guess whether the given ETag value is also an MD5 hash of an underlying object in a storage service, as opposed to being some other kind of opaque hash.static String
join(int[] ints, String delimiter)
Joins a list of ints into a delimiter-separated string.static String
join(Object[] items, String delimiter)
Joins a list of items into a delimiter-separated string.static String
join(List<?> items, String delimiter)
Joins a list of items into a delimiter-separated string.static XMLReader
loadXMLReader()
Find a SAX XMLReader by hook or by crook, with work-arounds for non-standard platforms.static Date
parseIso8601Date(String dateString)
static Date
parseRfc822Date(String dateString)
static String
readInputStreamLineToString(InputStream is, String encoding)
Reads from an input stream until a newline character or the end of the stream is reached.static byte[]
readInputStreamToBytes(InputStream is)
Reads binary data from an input stream and returns it as a byte array.static String
readInputStreamToString(InputStream is, String encoding)
Reads text data from an input stream and returns it as a String.static String
signWithHmacSha1(String awsSecretKey, String canonicalString)
Calculate the HMAC/SHA1 on a string.static String
toBase64(byte[] data)
Converts byte data to a Base64-encoded string.static String
toHex(byte[] data)
Converts byte data to a Hex-encoded string.
-
-
-
Method Detail
-
parseIso8601Date
public static Date parseIso8601Date(String dateString) throws ParseException
- Throws:
ParseException
-
parseRfc822Date
public static Date parseRfc822Date(String dateString) throws ParseException
- Throws:
ParseException
-
signWithHmacSha1
public static String signWithHmacSha1(String awsSecretKey, String canonicalString) throws ServiceException
Calculate the HMAC/SHA1 on a string.- Parameters:
awsSecretKey
- AWS secret key.canonicalString
- canonical string representing the request to sign.- Returns:
- Signature
- Throws:
ServiceException
-
readInputStreamToString
public static String readInputStreamToString(InputStream is, String encoding) throws IOException
Reads text data from an input stream and returns it as a String.- Parameters:
is
- input stream from which text data is read.encoding
- the character encoding of the textual data in the input stream. If this parameter is null, the default system encoding will be used.- Returns:
- text data read from the input stream.
- Throws:
IOException
-
readInputStreamLineToString
public static String readInputStreamLineToString(InputStream is, String encoding) throws IOException
Reads from an input stream until a newline character or the end of the stream is reached.- Parameters:
is
-- Returns:
- text data read from the input stream, not including the newline character.
- Throws:
IOException
-
readInputStreamToBytes
public static byte[] readInputStreamToBytes(InputStream is) throws IOException
Reads binary data from an input stream and returns it as a byte array.- Parameters:
is
- input stream from which data is read.- Returns:
- byte array containing data read from the input stream.
- Throws:
IOException
-
countBytesInObjects
public static long countBytesInObjects(S3Object[] objects)
Counts the total number of bytes in a set of S3Objects by summing the content length of each.- Parameters:
objects
-- Returns:
- total number of bytes in all S3Objects.
-
cleanRestMetadataMap
public static Map<String,Object> cleanRestMetadataMap(Map<String,Object> metadata, String headerPrefix, String metadataPrefix)
From a map of metadata returned from a REST GET or HEAD request, returns a map of metadata with the HTTP-connection-specific metadata items removed.- Parameters:
metadata
-- Returns:
- metadata map with HTTP-connection-specific items removed.
-
toHex
public static String toHex(byte[] data)
Converts byte data to a Hex-encoded string.- Parameters:
data
- data to hex encode.- Returns:
- hex-encoded string.
-
fromHex
public static byte[] fromHex(String hexData)
Converts a Hex-encoded data string to the original byte data.- Parameters:
hexData
- hex-encoded data to decode.- Returns:
- decoded data from the hex string.
-
toBase64
public static String toBase64(byte[] data)
Converts byte data to a Base64-encoded string.- Parameters:
data
- data to Base64 encode.- Returns:
- encoded Base64 string.
-
join
public static String join(List<?> items, String delimiter)
Joins a list of items into a delimiter-separated string. Each item is converted to a string value with the toString() method before being added to the final delimited list.- Parameters:
items
- the items to include in a delimited stringdelimiter
- the delimiter character or string to insert between each item in the list- Returns:
- a delimited string
-
join
public static String join(Object[] items, String delimiter)
Joins a list of items into a delimiter-separated string. Each item is converted to a string value with the toString() method before being added to the final delimited list.- Parameters:
items
- the items to include in a delimited stringdelimiter
- the delimiter character or string to insert between each item in the list- Returns:
- a delimited string
-
join
public static String join(int[] ints, String delimiter)
Joins a list of ints into a delimiter-separated string.- Parameters:
ints
- the ints to include in a delimited stringdelimiter
- the delimiter character or string to insert between each item in the list- Returns:
- a delimited string
-
fromBase64
public static byte[] fromBase64(String b64Data)
Converts a Base64-encoded string to the original byte data.- Parameters:
b64Data
- a Base64-encoded string to decode.- Returns:
- bytes decoded from a Base64 string.
-
computeMD5Hash
public static byte[] computeMD5Hash(InputStream is) throws NoSuchAlgorithmException, IOException
Computes the MD5 hash of the data in the given input stream and returns it as a hex string. The provided input stream is consumed and closed by this method.- Parameters:
is
-- Returns:
- MD5 hash
- Throws:
NoSuchAlgorithmException
IOException
-
computeMD5Hash
public static byte[] computeMD5Hash(byte[] data) throws NoSuchAlgorithmException, IOException
Computes the MD5 hash of the given data and returns it as a hex string.- Parameters:
data
-- Returns:
- MD5 hash.
- Throws:
NoSuchAlgorithmException
IOException
-
isEtagAlsoAnMD5Hash
public static boolean isEtagAlsoAnMD5Hash(String etag)
Guess whether the given ETag value is also an MD5 hash of an underlying object in a storage service, as opposed to being some other kind of opaque hash.This test was made necessary by Amazon S3's multipart upload feature, where the ETag value returned after a re-assembled multipart upload is completed is no longer the same as an MD5 hash of the assembled data.
An ETag is considered also an MD5 when:
- The length is exactly 16 characters (excluding surrounding quote characters)
- All characters in the string are hexadecimal values, i.e. [0-9a-f] when lowercased
These rules are drawn from the post by Carl@AWS on Nov 11, 2010 10:40 AM here: https://forums.aws.amazon.com/thread.jspa?messageID=222158&tstart=0
- Returns:
- true if the ETag value can be assumed to also be an MD5 hash.
-
findBucketNameInHostname
public static String findBucketNameInHostname(String host, String s3Endpoint)
Identifies the name of a bucket from a given host name, if available. Returns null if the bucket name cannot be identified, as might happen when a bucket name is represented by the path component of a URL instead of the host name component.- Parameters:
host
- the host name component of a URL that may include the bucket name, if an alternative host name is in use.- Returns:
- The S3 bucket name represented by the DNS host name, or null if none.
-
buildObjectFromUrl
public static S3Object buildObjectFromUrl(String host, String urlPath, String s3Endpoint) throws UnsupportedEncodingException
Builds an object based on the bucket name and object key information available in the components of a URL.- Parameters:
host
- the host name component of a URL that may include the bucket name, if an alternative host name is in use.urlPath
- the path of a URL that references an S3 object, and which may or may not include the bucket name.- Returns:
- the object referred to by the URL components.
- Throws:
UnsupportedEncodingException
-
isBucketNameValidDNSName
public static boolean isBucketNameValidDNSName(String bucketName)
Returns true if the given bucket name can be used as a component of a valid DNS name. If so, the bucket can be accessed using requests with the bucket name as part of an S3 sub-domain. If not, the old-style bucket reference URLs must be used, in which case the bucket name must be the first component of the resource path.- Parameters:
bucketName
- the name of the bucket to test for DNS compatibility.
-
generateS3HostnameForBucket
public static String generateS3HostnameForBucket(String bucketName, boolean isDnsBucketNamingDisabled, String s3Endpoint)
-
getUserAgentDescription
public static String getUserAgentDescription(String applicationDescription)
Returns a user agent string describing the jets3t library, and optionally the application using it, to server-side services.- Parameters:
applicationDescription
- a description of the application using the jets3t toolkit, included at the end of the user agent string. This value may be null.- Returns:
- a string built with the following components (some elements may not be available):
JetS3t/
Constants.JETS3T_VERSION
(os.name/os.version; os.arch; user.region; user.region; user.language) applicationDescription
-
loadXMLReader
public static XMLReader loadXMLReader() throws ServiceException
Find a SAX XMLReader by hook or by crook, with work-arounds for non-standard platforms.- Returns:
- an initialized XML SAX reader
- Throws:
ServiceException
-
-