com.objsys.asn1j.runtime

Class Asn1EncodeBitBuffer

java.lang.Object

com.objsys.asn1j.runtime.Asn1MessageBufferBase

com.objsys.asn1j.runtime.Asn1MessageBuffer

com.objsys.asn1j.runtime.Asn1EncodeBuffer

com.objsys.asn1j.runtime.Asn1EncodeBitBuffer

All Implemented Interfaces:

Asn1BitMessageBuffer, Asn1Writable

Direct Known Subclasses:

Asn1NasEncodeBuffer, Asn1OerEncodeBuffer, Asn1PerEncodeBuffer

public class Asn1EncodeBitBuffer
extends Asn1EncodeBuffer
implements Asn1BitMessageBuffer, Asn1Writable

An encoding buffer that is bit-oriented. This is useful when dealing with encoding rules where individual bits need to be written, such as PER.

Field Summary

Fields

Modifier and Type	Field and Description
protected int	mByteIndex
protected byte[]	mData
protected Asn1PerTraceHandler	mTraceHandler

Fields inherited from class com.objsys.asn1j.runtime.Asn1EncodeBuffer

INITIAL_SIZE

Fields inherited from class com.objsys.asn1j.runtime.Asn1MessageBufferBase

context, mTypeCode

Constructor Summary

Constructors

Constructor and Description
Asn1EncodeBitBuffer() The default constructor initializes the encode buffer to the default buffer size (INITIAL_SIZE bytes).
Asn1EncodeBitBuffer(int size) This constructor allows specification of the initial size.

Method Summary

Modifier and Type	Method and Description
void	binDump(java.io.PrintStream out, java.lang.String varName) This method dumps the encoded message in a human-readable format showing a bit trace of all fields to the given print output stream.
void	byteAlign() Byte-align the buffer, possibly conditionally.
protected void	checkSize(int bytesRequired) This method determines if the encode buffer can hold the requested number of additional bytes.
void	copy(byte value) This method is used to copy a single byte to the encode buffer.
void	copy(byte[] value, int offset, int len) This method copies multiple bytes from the given array to the encode buffer.
void	encodeBit(boolean value) This method encodes a single bit value.
void	encodeBits(byte[] value, int offset, int nbits) This method encodes bit values from an array of octets.
void	encodeBits(byte[] value, int offset, int bitOffset, int nbits) This method encodes bit values from an array of octets.
void	encodeBits(byte value, int nbits) This method encodes bit values from an octet.
void	encodeLongBits(long value, int nbits) This method encodes bit values from a long.
void	encodeLongBits(long value, int nbits, boolean merge) This method encodes bit values from a long.
int	getBitOffsetInByte() Return the bit offset of the next bit to be encoded.
byte[]	getBuffer() This method returns a reference to the byte buffer used to hold the encoded message.
java.io.ByteArrayInputStream	getByteArrayInputStream() This method returns a reference to a byte array input stream representing the encoded message.
int	getByteIndex() This method returns the current byte index into the encode buffer.
int	getMsgBitCnt() This method returns the number of bits in the encoded message.
int	getMsgByteCnt() This method returns the number of bytes written to the buffer.
byte[]	getMsgCopy() This method returns the encoded message in a byte array.
int	getMsgLength() This method returns the length (in bytes) of the encoded message component.
Asn1PerTraceHandler	getTraceHandler() This method will return a reference to the internal trace handler object used to trace the bit fields within a PER message.
void	hexDump() This method dumps the encoded message in hex/ascii format to the standard output stream.
boolean	isByteAligned() Return true/false indicating whether a multiple of 8 bits has been encoded thus far.
void	reset() This method resets the buffer object so that it can be reused to encode another message.
void	reverseBytes(int offset, int nbytes) This method reverses a series of bytes at a given offset within the encode buffer.
void	setMsgBitCnt(int count) This method sets the position in the encoded message such that getMsgBitCnt will subsequently return the given number.
java.lang.String	toString() This method will return a string representation of the data in the encode buffer.
void	write(byte[] value) Implements Asn1Writable.write
void	write(byte[] value, int offset, int len) Implements Asn1Writable.write
void	write(int value) Implements Asn1Writable.write
void	write(java.io.OutputStream out) This method writes the encoded record to the given output stream.

Methods inherited from class com.objsys.asn1j.runtime.Asn1EncodeBuffer

binDump, copy, encodeIntSigned, encodeIntUnsigned, getInputStream, getMinimalOctetsSigned, getMinimalOctetsUnsigned, getOutputStream, hexDump

Methods inherited from class com.objsys.asn1j.runtime.Asn1MessageBuffer

addNamedEventHandler, getEventHandlerListCount, hasEventHandlers, invokeCharacters, invokeEndElement, invokeStartElement, setEventHandlerList

Methods inherited from class com.objsys.asn1j.runtime.Asn1MessageBufferBase

getContext, hexDump, hexDump, setKey, setTypeCode

Methods inherited from class java.lang.Object

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

Methods inherited from interface com.objsys.asn1j.runtime.Asn1BitMessageBuffer

getInputStream

Field Detail

mByteIndex

protected int mByteIndex

mData

protected byte[] mData

mTraceHandler

protected Asn1PerTraceHandler mTraceHandler

Constructor Detail

Asn1EncodeBitBuffer

public Asn1EncodeBitBuffer()

The default constructor initializes the encode buffer to the default buffer size (INITIAL_SIZE bytes).

Asn1EncodeBitBuffer

public Asn1EncodeBitBuffer(int size)

This constructor allows specification of the initial size. This overrides the INITIAL_SIZE constant value.

Parameters:

size - initial Buffer size

Method Detail

byteAlign

public void byteAlign()

Byte-align the buffer, possibly conditionally. This class implements this method to unconditionally byte-align. Subclasses, however, may override this (as PER does) to only byte-align under certain conditions (such as when aligned PER is specified).

Specified by:

byteAlign in interface Asn1BitMessageBuffer

isByteAligned

public final boolean isByteAligned()

Return true/false indicating whether a multiple of 8 bits has been encoded thus far.

getTraceHandler

public Asn1PerTraceHandler getTraceHandler()

This method will return a reference to the internal trace handler object used to trace the bit fields within a PER message.

Specified by:

getTraceHandler in interface Asn1BitMessageBuffer

binDump

public void binDump(java.io.PrintStream out,
                    java.lang.String varName)

This method dumps the encoded message in a human-readable format showing a bit trace of all fields to the given print output stream.

Specified by:

binDump in class Asn1EncodeBuffer

Parameters:

out - stream to print to.

varName - Variable name to include in output.

checkSize

protected final void checkSize(int bytesRequired)

This method determines if the encode buffer can hold the requested number of additional bytes. If not, the buffer is expanded. This implementation assumes mByteIndex is used, and that the array is filling from 0..n.

Parameters:

bytesRequired - Number of required bytes.

copy

public void copy(byte value)

This method is used to copy a single byte to the encode buffer.

Specified by:

copy in class Asn1EncodeBuffer

Parameters:

value - The byte value to copy

copy

public void copy(byte[] value,
                 int offset,
                 int len)
          throws Asn1Exception

This method copies multiple bytes from the given array to the encode buffer.

Specified by:

copy in class Asn1EncodeBuffer

Parameters:

value -

offset - The first byte copied is value[offset]

len - The last byte copied is value[offset + len - 1]

Throws:

Asn1Exception

getBitOffsetInByte

public final int getBitOffsetInByte()

Return the bit offset of the next bit to be encoded. This returns 7 for the most significant bit, and 0 for the least significant bit.

Returns:

getBuffer

public byte[] getBuffer()

This method returns a reference to the byte buffer used to hold the encoded message. (This is dangerous!)

Returns:

Byte buffer reference

getByteArrayInputStream

public java.io.ByteArrayInputStream getByteArrayInputStream()

This method returns a reference to a byte array input stream representing the encoded message. This is the preferred way to access the contents of the encoded message as it is the most efficient.

Specified by:

getByteArrayInputStream in class Asn1EncodeBuffer

Returns:

byte array input stream containing encoded message

getMsgBitCnt

public final int getMsgBitCnt()

This method returns the number of bits in the encoded message.

Specified by:

getMsgBitCnt in interface Asn1BitMessageBuffer

Returns:

Count of bits in encoded message

setMsgBitCnt

public final void setMsgBitCnt(int count)

This method sets the position in the encoded message such that getMsgBitCnt will subsequently return the given number.

Parameters:

count - The number of bits. This many bits must fit within the current buffer.

getMsgCopy

public final byte[] getMsgCopy()

This method returns the encoded message in a byte array. This is less efficient than the getInputStream method because the message contents must be copied to a newly created byte array.

Specified by:

getMsgCopy in class Asn1EncodeBuffer

Returns:

byte array containing encoded message

encodeBit

public void encodeBit(boolean value)

This method encodes a single bit value.

Parameters:

value - Boolean value of bit to be encoded.

encodeLongBits

public final void encodeLongBits(long value,
                                 int nbits)

This method encodes bit values from a long. The least significant nbits bits of the long value are encoded.

encodeLongBits

public final void encodeLongBits(long value,
                                 int nbits,
                                 boolean merge)

This method encodes bit values from a long. The least significant nbits bits of the long value are encoded.

Parameters:

value - The value to take bits from

nbits - The number of bits to encode

merge - If true, preserve bits that follow the encoded bits in any bytes that are touched. This can be set when overwriting certain bits within an encoding.

encodeBits

public final void encodeBits(byte value,
                             int nbits)
                      throws Asn1InvalidArgException

This method encodes bit values from an octet. The most significant bits from the octet are encoded.

Parameters:

value - Octet containing bits to be encoded

nbits - Number of bits to encode

Throws:

Asn1InvalidArgException

encodeBits

public void encodeBits(byte[] value,
                       int offset,
                       int bitOffset,
                       int nbits)
                throws Asn1InvalidArgException

This method encodes bit values from an array of octets.

Parameters:

value - Octet array containing bits to be encoded

offset - Starting byte offset in value

bitOffset - Starting bit offset in first byte. Pass 0 to begin encoding with the most significant bit. Pass 7 to begin with the least significant bit.

nbits - Number of bits to encode

Throws:

Asn1InvalidArgException

encodeBits

public void encodeBits(byte[] value,
                       int offset,
                       int nbits)
                throws Asn1InvalidArgException

This method encodes bit values from an array of octets.

Parameters:

value - Octet array containing bits to be encoded

offset - Starting byte offset in value

nbits - Number of bits to encode

Throws:

Asn1InvalidArgException

getByteIndex

public int getByteIndex()

This method returns the current byte index into the encode buffer.

Returns:

Byte index value

getMsgByteCnt

public int getMsgByteCnt()

This method returns the number of bytes written to the buffer. If the last byte written to is a partial byte, it is counted as a full byte.

Returns:

Count of bytes in encoded message

getMsgLength

public int getMsgLength()

This method returns the length (in bytes) of the encoded message component.

Specified by:

getMsgLength in class Asn1EncodeBuffer

Returns:

length of encoded message component

write

public void write(int value)

Implements Asn1Writable.write

Specified by:

write in interface Asn1Writable

Parameters:

value - the byte.

write

public void write(byte[] value)

Implements Asn1Writable.write

Specified by:

write in interface Asn1Writable

Parameters:

value - the data.

write

public void write(byte[] value,
                  int offset,
                  int len)

Implements Asn1Writable.write

Specified by:

write in interface Asn1Writable

Parameters:

value - the data.

offset - the start offset in the data.

len - the number of bytes to write.

reset

public void reset()

This method resets the buffer object so that it can be reused to encode another message. Any previously encoded data is lost.

Specified by:

reset in class Asn1EncodeBuffer

reverseBytes

public void reverseBytes(int offset,
                         int nbytes)

This method reverses a series of bytes at a given offset within the encode buffer.

Parameters:

offset - Starting byte offset within the buffer

nbytes - Number of bytes to reverse

write

public final void write(java.io.OutputStream out)
                 throws java.io.IOException

This method writes the encoded record to the given output stream.

Specified by:

write in class Asn1EncodeBuffer

Parameters:

out - Output stream to which record is to be written

Throws:

java.io.IOException - for any I/O error.

toString

public java.lang.String toString()

This method will return a string representation of the data in the encode buffer. The format is hex characters.

Overrides:

toString in class java.lang.Object

Returns:

Stringified representation of the value

hexDump

public void hexDump()

This method dumps the encoded message in hex/ascii format to the standard output stream.

Overrides:

hexDump in class Asn1EncodeBuffer