org.jets3t.service.utils
Class ServiceUtils

java.lang.Object
  extended by org.jets3t.service.utils.ServiceUtils

public class ServiceUtils
extends Object

General utility methods used throughout the jets3t project.

Author:
James Murty

Constructor Summary
ServiceUtils()
           
 
Method Summary
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 cleanRestMetadataMap(Map metadata)
          From a map of metadata returned from a REST Get Object or Get Object 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 String join(int[] ints, String delimiter)
          Joins a list of ints into a delimiter-separated string.
static String join(List items, String delimiter)
          Joins a list of items into a delimiter-separated string.
static String join(Object[] 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.
 
Methods inherited from class java.lang.Object
equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

ServiceUtils

public ServiceUtils()
Method Detail

parseIso8601Date

public static Date parseIso8601Date(String dateString)
                             throws ParseException
Throws:
ParseException

formatIso8601Date

public static String formatIso8601Date(Date date)

parseRfc822Date

public static Date parseRfc822Date(String dateString)
                            throws ParseException
Throws:
ParseException

formatRfc822Date

public static String formatRfc822Date(Date date)

signWithHmacSha1

public static String signWithHmacSha1(String awsSecretKey,
                                      String canonicalString)
                               throws S3ServiceException
Calculate the HMAC/SHA1 on a string.

Parameters:
awsSecretKey - AWS secret key.
canonicalString - canonical string representing the request to sign.
Returns:
Signature
Throws:
S3ServiceException

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 cleanRestMetadataMap(Map metadata)
From a map of metadata returned from a REST Get Object or Get Object 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 string
delimiter - 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 string
delimiter - 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 string
delimiter - 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

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/S3Service.VERSION_NO__JETS3T_TOOLKIT (os.name/os.version; os.arch; user.region; user.region; user.language) applicationDescription

loadXMLReader

public static XMLReader loadXMLReader()
                               throws S3ServiceException
Find a SAX XMLReader by hook or by crook, with work-arounds for non-standard platforms.

Returns:
an initialized XML SAX reader
Throws:
S3ServiceException