Package org.bouncycastle.openpgp

Class PGPLiteralDataGenerator

java.lang.Object

org.bouncycastle.openpgp.PGPLiteralDataGenerator

public class PGPLiteralDataGenerator
extends Object

Generator for producing literal data packets.

A PGPLiteralData is used by invoking one of the open functions to create an OutputStream that raw data can be supplied to for encoding:

• If the length of the data to be written is known in advance, use open(OutputStream, char, String, long, Date) to create a packet containing a single literal data object.
• If the length of the data is unknown, use open(OutputStream, char, String, Date, byte[]) to create a packet consisting of a series of literal data objects (partials).

A PGPLiteralDataGenerator is usually used to wrap the OutputStream obtained from a PGPEncryptedDataGenerator or a PGPCompressedDataGenerator.

Once literal data has been written to the constructed OutputStream, writing of the object stream is completed by closing the OutputStream obtained from the open() method, or equivalently invoking close() on this generator.

Field Summary

Fields

Modifier and Type	Field	Description
static final char	BINARY	Format tag for binary literal data
static final String	CONSOLE	The special name indicating a "for your eyes only" packet.
static final Date	NOW	The special time for a modification time of "now" or the present time.
static final char	TEXT	Format tag for textual literal data
static final char	UTF8	Format tag for UTF-8 encoded textual literal data

Constructor Summary

Constructors

Constructor	Description
PGPLiteralDataGenerator()	Constructs a generator for literal data objects.
PGPLiteralDataGenerator(boolean oldFormat)	Constructs a generator for literal data objects, specifying to use new or old (PGP 2.6.x compatible) format.

Method Summary

Modifier and Type	Method	Description
void	close()	Close the literal data packet - this is equivalent to calling close on the stream returned by the open() method.
OutputStream	open(OutputStream out, char format, File file)	Open a literal data packet for the passed in File object, returning an output stream for saving the file contents.
OutputStream	open(OutputStream out, char format, String name, long length, Date modificationTime)	Open a literal data packet, returning a stream to store the data inside the packet.
OutputStream	open(OutputStream out, char format, String name, Date modificationTime, byte[] buffer)	Open a literal data packet, returning a stream to store the data inside the packet as an indefinite-length stream.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Details

BINARY

public static final char BINARY

Format tag for binary literal data

See Also:

• Constant Field Values

TEXT

public static final char TEXT

Format tag for textual literal data

See Also:

• Constant Field Values

UTF8

public static final char UTF8

Format tag for UTF-8 encoded textual literal data

See Also:

• Constant Field Values

CONSOLE

public static final String CONSOLE

The special name indicating a "for your eyes only" packet.

See Also:

• Constant Field Values

NOW

public static final Date NOW

The special time for a modification time of "now" or the present time.

Constructor Details

PGPLiteralDataGenerator

public PGPLiteralDataGenerator()

Constructs a generator for literal data objects.

PGPLiteralDataGenerator

public PGPLiteralDataGenerator(boolean oldFormat)

Constructs a generator for literal data objects, specifying to use new or old (PGP 2.6.x compatible) format.

This can be used for compatibility with PGP 2.6.x.

Parameters:

oldFormat - true to use PGP 2.6.x compatible format.

Method Details

open

public OutputStream open(OutputStream out,
 char format,
 String name,
 long length,
 Date modificationTime)
                  throws IOException

Open a literal data packet, returning a stream to store the data inside the packet.

The stream created can be closed off by either calling close() on the stream or close() on the generator. Closing the returned stream does not close off the OutputStream parameter out.

Parameters:

out - the underlying output stream to write the literal data packet to.

format - the format of the literal data that will be written to the output stream (one of BINARY, TEXT or UTF8).

name - the name of the "file" to encode in the literal data object.

length - the length of the data that will be written.

modificationTime - the time of last modification we want stored.

Throws:

IOException

open

public OutputStream open(OutputStream out,
 char format,
 String name,
 Date modificationTime,
 byte[] buffer)
                  throws IOException

Open a literal data packet, returning a stream to store the data inside the packet as an indefinite-length stream. The stream is written out as a series of partial packets with a chunk size determined by the size of the passed in buffer.

The stream created can be closed off by either calling close() on the stream or close() on the generator. Closing the returned stream does not close off the OutputStream parameter out.

Note: if the buffer is not a power of 2 in length only the largest power of 2 bytes worth of the buffer will be used.

Parameters:

out - the underlying output stream to write the literal data packet to.

format - the format of the literal data that will be written to the output stream (one of BINARY, TEXT or UTF8).

name - the name of the "file" to encode in the literal data object.

modificationTime - the time of last modification we want stored (will be stored to second level precision).

buffer - a buffer to use to buffer and write partial packets. The returned stream takes ownership of the buffer.

Returns:

the output stream to write data to.

Throws:

IOException - if an error occurs writing stream header information to the provider output stream.

IllegalStateException - if this generator already has an open OutputStream.

open

public OutputStream open(OutputStream out,
 char format,
 File file)
                  throws IOException

Open a literal data packet for the passed in File object, returning an output stream for saving the file contents.

This method configures the generator to store the file contents in a single literal data packet, taking the filename and modification time from the file, but does not store the actual file data.

The stream created can be closed off by either calling close() on the stream or close() on the generator. Closing the returned stream does not close off the OutputStream parameter out.

Parameters:

out - the underlying output stream to write the literal data packet to.

format - the format of the literal data that will be written to the output stream (one of BINARY, TEXT or UTF8).

file - the file to determine the length and filename from.

Returns:

the output stream to write data to.

Throws:

IOException - if an error occurs writing stream header information to the provider output stream.

IllegalStateException - if this generator already has an open OutputStream.

close

public void close()
           throws IOException

Close the literal data packet - this is equivalent to calling close on the stream returned by the open() method.

Throws:

IOException