Class ASCII85Decode

java.lang.Object

org.openpdf.renderer.decode.ASCII85Decode

public class ASCII85Decode
extends Object

decode ASCII85 text into a byte array.

Field Summary

Fields

Modifier and Type	Field	Description
private ByteBuffer	buf

Constructor Summary

Constructors

Modifier	Constructor	Description
private	ASCII85Decode(ByteBuffer buf)	initialize the decoder with byte buffer in ASCII85 format

Method Summary

Modifier and Type	Method	Description
private ByteBuffer	decode()	decode the bytes
static ByteBuffer	decode(ByteBuffer buf, PDFObject params)	decode an array of bytes in ASCII85 format.
private boolean	decode5(ByteArrayOutputStream baos)	decode the next five ASCII85 characters into up to four decoded bytes.
private int	nextChar()	get the next character from the input.

Methods inherited from class Object

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

Field Details

buf

private ByteBuffer buf

Constructor Details

ASCII85Decode

private ASCII85Decode(ByteBuffer buf)

initialize the decoder with byte buffer in ASCII85 format

Method Details

nextChar

private int nextChar()

get the next character from the input.

Returns:

the next character, or -1 if at end of stream

decode5

private boolean decode5(ByteArrayOutputStream baos)
                 throws PDFParseException

decode the next five ASCII85 characters into up to four decoded bytes. Return false when finished, or true otherwise.

Parameters:

baos - the ByteArrayOutputStream to write output to, set to the correct position

Returns:

false when finished, or true otherwise.

Throws:

PDFParseException

decode

private ByteBuffer decode()
                   throws PDFParseException

decode the bytes

Returns:

the decoded bytes

Throws:

PDFParseException

decode

public static ByteBuffer decode(ByteBuffer buf,
 PDFObject params)
                         throws PDFParseException

decode an array of bytes in ASCII85 format.

In ASCII85 format, every 5 characters represents 4 decoded bytes in base 85. The entire stream can contain whitespace, and ends in the characters '~>'.

Parameters:

buf - the encoded ASCII85 characters in a byte buffer

params - parameters to the decoder (ignored)

Returns:

the decoded bytes

Throws:

PDFParseException