CompressedDataStream ("Entrust Authority Security Toolkit for the Java Platform")

java.lang.Object
- iaik.cms.CompressedDataStream

All Implemented Interfaces:

ContentStream

Direct Known Subclasses:

CompressedData, SMimeCompressed
```
public class CompressedDataStream
extends java.lang.Object
implements ContentStream
```
This class represents the stream supporting implementation of the CMS CompressedData type. The compressed-data content type is identified by the following object identifier:
```
 
  
    id-ct-compressedData OBJECT IDENTIFIER ::= { iso(1) member-body(2)
          us(840) rsadsi(113549) pkcs(1) pkcs-9(9) smime(16) ct(1) 9 }
   
  
 
```
which refers to the OID "1.2.840.113549.1.9.16.1.9".
The CompressedData type provides a means for compressing or decompressing the content of a CMS message. The algorithm identifier identifies the compression algorithm to be used. The ZLIB compression algorithm is used as the default algorithm for compressing the EncapsulatedContent(as defined by RFC 3274). ZLIB compression is defined in RFC1950 and RFC 1951.
```
 
   
     CompressedData ::= SEQUENCE {
        version CMSVersion,
        compressionAlgorithm CompressionAlgorithmIdentifier,
        encapContentInfo EncapsulatedContentInfo
     }
   
  
 
```

Field Summary

Fields
Modifier and Type	Field and Description
`static ObjectID`	`contentType` The object identifier which specifies the CMS compressed data, see RFC 3274
`static int`	`DEFAULT_BLOCKSIZE` The Default blocksize set to 2048 bytes
`static int`	`EXPLICIT` Used to determine if data is explicitly compressed
`static int`	`IMPLICIT` Used to determine if data is implicitly compressed
`protected int`	`m_blockSize` The user defined blocksize
`protected AlgorithmID`	`m_compressionAlgorithm` The compression algorithm ID
`protected ObjectID`	`m_encapContentType` The encapulsted content type
`protected java.io.InputStream`	`m_inputStream` The input stream used to compress data
`protected int`	`m_version` The SMIME version, should be 0

Constructor Summary

Constructors
Modifier	Constructor and Description
`protected`	`CompressedDataStream()` Default constructor for dynamic object creation in ContentInfoStream.
	`CompressedDataStream(java.io.InputStream inputstream)` Creates a new CompressedDataStream where the BER encoded data is read from the given InputStream.
	`CompressedDataStream(java.io.InputStream inputstream, AlgorithmID algorithmid, int mode)` Creates a new CMS CompressedDataStream object where the content to be compressed is read from the supplied InputStream.
	`CompressedDataStream(ObjectID objectid, java.io.InputStream inputstream, AlgorithmID algorithmid, int mode)` Creates a new CompressedDataStream object for the given content data.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`void`	`decode(java.io.InputStream inputstream)` Reads and decodes an encoded CompressedDataStream from an input stream.
`int`	`getBlockSize()` Gets the block size defining the length of each definite primitive encoded octet string component.
`AlgorithmID`	`getCompressionAlgorithm()` Returns the compression algorithm
`CompressionProvider`	`getCompressionProvider()` Returns the CompressionProvider
`ObjectID`	`getContentType()` Returns the content type this class implements.
`EncapsulatedContentInfoStream`	`getEncapsulatedContentInfoStream()` Returns the EncapsulatedContentInfoStream.
`ObjectID`	`getEncapsulatedContentType()` Returns the content type the EncapsulatetContentInfo represents.
`java.io.InputStream`	`getInputStream()` Returns an InputStream from where the compressed data can be read.
`int`	`getMode()` Returns the mode of this CompressedData.
`int`	`getVersion()` Returns the version of SMime compresssion being used (0)
`void`	`setBlockSize(int blocksize)` Sets the block size for defining the length of each definite primitive encoded octet string component.
`void`	`setCompressionProvider(CompressionProvider compressionprovider)` Sets the CompressionProvider for this CompressedDataStream.
`void`	`setInputStream(java.io.InputStream inputstream)` Sets the content supplying input stream.
`ASN1Object`	`toASN1Object()` Returns this CMS CompressedDataStream as an ASN1Object.
`protected ASN1Object`	`toASN1Object(int blocksize)` Returns this CMS `CompressedData` as ASN1Object.
`java.lang.String`	`toString()` Returns a string giving some information about this `CompressedDataStream` object.
`java.lang.String`	`toString(boolean detailed)` Returns a string giving some - if requested - detailed information about this `CompressedDataStream` object.
`void`	`writeTo(java.io.OutputStream outputstream)` BER encodes and writes this CompressedData to the supplied output stream.
`void`	`writeTo(java.io.OutputStream outputstream, int blocksize)` Writes this CompressedData encoded to the supplied output stream.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

- Field Detail
  - m_inputStream
```
protected java.io.InputStream m_inputStream
```
    The input stream used to compress data
  - m_blockSize
```
protected int m_blockSize
```
    The user defined blocksize
  - m_encapContentType
```
protected ObjectID m_encapContentType
```
    The encapulsted content type
  - m_compressionAlgorithm
```
protected AlgorithmID m_compressionAlgorithm
```
    The compression algorithm ID
  - m_version
```
protected int m_version
```
    The SMIME version, should be 0
  - DEFAULT_BLOCKSIZE
```
public static final int DEFAULT_BLOCKSIZE
```
    The Default blocksize set to 2048 bytes
    
    See Also:
    
    Constant Field Values
  - EXPLICIT
```
public static final int EXPLICIT
```
    Used to determine if data is explicitly compressed
    
    See Also:
    
    Constant Field Values
  - IMPLICIT
```
public static final int IMPLICIT
```
    Used to determine if data is implicitly compressed
    
    See Also:
    
    Constant Field Values
  - contentType
```
public static final ObjectID contentType
```
    The object identifier which specifies the CMS compressed data, see RFC 3274
- Constructor Detail
  - CompressedDataStream
```
public CompressedDataStream(java.io.InputStream inputstream,
                            AlgorithmID algorithmid,
                            int mode)
```
    Creates a new CMS CompressedDataStream object where the content to be compressed is read from the supplied InputStream. The mode parameter specifies whether to include the compressed data (mode = CompressedDataStream.IMPLICIT) or not include it (mode = CompressedDataStream.EXPLICIT). The content type of the inherent EncapsulatedContentInfo automatically is set to CMS Data.
    
    Parameters:
    
    inputstream - the InputStream containing the data to encrypt
    
    algorithmid - algorithm used to compress the data
    
    mode - either CompressedDataStream.IMPLICIT for including the compressed data, or CompressedDataStream.EXPLICIT for not including it
  - CompressedDataStream
```
public CompressedDataStream(java.io.InputStream inputstream)
                     throws CMSParsingException,
                            java.io.IOException
```
    Creates a new CompressedDataStream where the BER encoded data is read from the given InputStream.
    
    Parameters:
    
    inputstream - the InputStream holding a BER encoded EncryptedDataStream object
    
    Throws:
    
    java.io.IOException - if an I/O error occurs during reading from the InputStream
    
    CMSParsingException - if an error occurs while parsing the object
  - CompressedDataStream
```
public CompressedDataStream(ObjectID objectid,
                            java.io.InputStream inputstream,
                            AlgorithmID algorithmid,
                            int mode)
```
    Creates a new CompressedDataStream object for the given content data. The data to be compressed is supplied from an input stream. The mode parameter specifies whether to include the compressed data (mode = CompressedDataStream.IMPLICIT) or not include it (mode = CompressedDataStream.EXPLICIT).
    
    Parameters:
    
    objectid - the content type (e.g. ObjectID.cms_data) of the data to be compressed
    
    inputstream - the data to be compressed, supplied from an input stream
    
    algorithmid - the compression algorithm to be used for content compression
    
    mode - either CompressedDataStream.IMPLICIT for including the compressed data, or CompressedDataStream.EXPLICIT for not including it
  - CompressedDataStream
```
protected CompressedDataStream()
```
    Default constructor for dynamic object creation in ContentInfoStream.
- Method Detail
  - writeTo
```
public void writeTo(java.io.OutputStream outputstream,
                    int blocksize)
             throws java.io.IOException
```
    Writes this CompressedData encoded to the supplied output stream. If block size has a value > 0, in implicit mode the inherent compressed data is encoded as constructed OCTET STRING. In this case the encoding is splitted according to the defined block size:
```
 
  
   * 0x24 0x80
           0x04 <blocksize> <data>
           0x04 <blocksize> <data>
           0x04 <blocksize> <data>
                ...
    0x00 0x00
   
  
 
```
    If the block size is not positive, the whole data is encoded as one single primitive definie octet string:
```
 
  
   0x04 <length> <data>
   
  
 
```
    Parameters:
    
    outputstream - the output stream to which this SignedData shall be written
    
    blocksize - the block size defining the encoding scheme - and specifying the length of each primitive encoded octet string component, if positive
    
    Throws:
    
    java.io.IOException - if an error occurs during writing the object
  - writeTo
```
public void writeTo(java.io.OutputStream outputstream)
             throws java.io.IOException
```
    BER encodes and writes this CompressedData to the supplied output stream.
    
    Parameters:
    
    outputstream - the output stream to which this EnvelopedData shall be written
    
    Throws:
    
    java.io.IOException
  - toString
```
public java.lang.String toString(boolean detailed)
```
    Returns a string giving some - if requested - detailed information about this CompressedDataStream object.
    
    Specified by:
    
    toString in interface ContentStream
    
    Parameters:
    
    detailed - - whether or not to give detailed information
    
    Returns:
    
    the string representation
  - toString
```
public java.lang.String toString()
```
    Returns a string giving some information about this CompressedDataStream object.
    
    Overrides:
    
    toString in class java.lang.Object
    
    Returns:
    
    the string representation
  - toASN1Object
```
protected ASN1Object toASN1Object(int blocksize)
                           throws CMSException
```
    Returns this CMS CompressedData as ASN1Object.
    Note: If AlgorithmID parameters are not set, this method will encode the AlgorithmIdentifier with only the algorithm ObjectID (as per RFC 3274 section 2.1 recommendations).
    For Example:
    Without Algorithm Parameters, AlgorithmIdentifier will be encoded as follows:
```
 
  
   AlgorithmIdentifier  ::=  SEQUENCE  {
        algorithm               OBJECT IDENTIFIER }
   
  
 
```
    With Algorithm Parameters, AlgorithmIdentifier will be encoded as follows:
```
 
  
   AlgorithmIdentifier  ::=  SEQUENCE  {
        algorithm               OBJECT IDENTIFIER,
        parameters              ANY DEFINED BY algorithm  }
   
  
 
```
    Parameters:
    
    blocksize - the block size defining the encoding scheme - and specifying the length of each primitive encoded octet string component, if positive
    
    Returns:
    
    this CompressedData as ASN1Object
    
    Throws:
    
    CMSException - if the ASN1Object could not be created
  - toASN1Object
```
public ASN1Object toASN1Object()
                        throws CMSException
```
    Returns this CMS CompressedDataStream as an ASN1Object.
    
    Specified by:
    
    toASN1Object in interface ContentStream
    
    Returns:
    
    this CompressedData as ASN1Object.
    
    Throws:
    
    CMSException - if the ASN1Object could not be created
  - setCompressionProvider
```
public void setCompressionProvider(CompressionProvider compressionprovider)
```
    Sets the CompressionProvider for this CompressedDataStream. This method allows to explicitly set a CompressionProvider for this CompressedDataStream. If no explicit CompressionProvider is set, the default CompressionProvider will be used for the required cryptographic operations.
    This class may use the following method of the CompressionProvider, which may be overriden by an application, if required:
    getInputStreamCompressEngine() to get an InputStreamCompressEngine through which the data is to be piped for data compression/decompression
    
    Parameters:
    
    compressionprovider - the CompressionProvider
  - getCompressionProvider
```
public CompressionProvider getCompressionProvider()
```
    Returns the CompressionProvider
    
    Returns:
    
    CompressionProvider
  - setInputStream
```
public void setInputStream(java.io.InputStream inputstream)
                    throws java.io.IOException,
                           java.security.NoSuchAlgorithmException
```
    Sets the content supplying input stream. When having created a new CompressedDataStream object to be encoded to a stream, this method may be used to supply the content to be compressed. When having decoded and parsed a received CompressedDataStream object coming from some stream, this method may be used for supplying the compressed content transmitted by other means.
    
    Parameters:
    
    inputstream - an input stream supplying the content to be compressed/decompressed
    
    Throws:
    
    java.io.IOException - - if an I/O error occurs
    
    java.security.NoSuchAlgorithmException - - if the compression algorithm is not supported
  - setBlockSize
```
public void setBlockSize(int blocksize)
```
    Sets the block size for defining the length of each definite primitive encoded octet string component. If the value of blockSize is smaller or equal to zero the whole data is encoded as definite primitive octet string.
    
    Specified by:
    
    setBlockSize in interface ContentStream
    
    Parameters:
    
    blocksize - for defining the encoding scheme and setting the octet string component length, if positive
  - getVersion
```
public int getVersion()
```
    Returns the version of SMime compresssion being used (0)
    
    Returns:
    
    version of SMime Compression (0)
  - getMode
```
public int getMode()
```
    Returns the mode of this CompressedData.
    
    Returns:
    
    IMPLICIT (1) or EXPLICIT (2)
  - getInputStream
```
public java.io.InputStream getInputStream()
                                   throws java.io.IOException,
                                          java.security.NoSuchAlgorithmException
```
    Returns an InputStream from where the compressed data can be read. Attention! The stream only may be read once.
    When having created a new CompressedDataStream object to be encoded to a stream, this method should only be called in EXPLICT mode to get and read away the compressed content to be transmitted by other means. In IMPLICT mode this method shall not be called at all since the compressed content has to be included in the CompressedData message (and therefore should not be read "away"). When having decoded and parsed a received CompressedDataStream object coming from some stream, this method may be used for obtaining the raw (decompressed) content.
    
    Returns:
    
    an InputStream for reading the decrypted data
    
    Throws:
    
    java.io.IOException
    
    java.security.NoSuchAlgorithmException
  - getEncapsulatedContentType
```
public ObjectID getEncapsulatedContentType()
```
    Returns the content type the EncapsulatetContentInfo represents.
  - getEncapsulatedContentInfoStream
```
public EncapsulatedContentInfoStream getEncapsulatedContentInfoStream()
```
    Returns the EncapsulatedContentInfoStream.
  - getContentType
```
public ObjectID getContentType()
```
    Returns the content type this class implements.
    
    Specified by:
    
    getContentType in interface ContentStream
    
    Returns:
    
    ObjectID.cms_compressedData ("1.2..840.113549.1.9.16.1.9")
  - getCompressionAlgorithm
```
public AlgorithmID getCompressionAlgorithm()
```
    Returns the compression algorithm
  - getBlockSize
```
public int getBlockSize()
```
    Gets the block size defining the length of each definite primitive encoded octet string component. If the value of blockSize is smaller or equal to zero the whole data is encoded as definite primitive octet string.
    
    Specified by:
    
    getBlockSize in interface ContentStream
    
    Returns:
    
    blockSize defining the encoding scheme and setting the octet string component length, if positive
  - decode
```
public void decode(java.io.InputStream inputstream)
            throws CMSParsingException,
                   java.io.IOException
```
    Reads and decodes an encoded CompressedDataStream from an input stream.
    
    Specified by:
    
    decode in interface ContentStream
    
    Parameters:
    
    inputstream - the InputStream supplying an encoded CompressedData object
    
    Throws:
    
    java.io.IOException - if an I/O error occurs during reading from the InputStream
    
    CMSParsingException - if an error occurs while parsing the object

Class CompressedDataStream

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

m_inputStream

m_blockSize

m_encapContentType

m_compressionAlgorithm

m_version

DEFAULT_BLOCKSIZE

EXPLICIT

IMPLICIT

contentType

Constructor Detail

CompressedDataStream

CompressedDataStream

CompressedDataStream

CompressedDataStream

Method Detail

writeTo

writeTo

toString

toString

toASN1Object

toASN1Object

setCompressionProvider

getCompressionProvider

setInputStream

setBlockSize

getVersion

getMode

getInputStream

getEncapsulatedContentType

getEncapsulatedContentInfoStream

getContentType

getCompressionAlgorithm

getBlockSize

decode