com.objsys.asn1j.runtime

Class Asn1OerDecodeBuffer

java.lang.Object

com.objsys.asn1j.runtime.Asn1MessageBufferBase

com.objsys.asn1j.runtime.Asn1MessageBuffer

com.objsys.asn1j.runtime.Asn1DecodeBuffer

com.objsys.asn1j.runtime.Asn1DecodeBitBuffer

com.objsys.asn1j.runtime.Asn1OerDecodeBuffer

All Implemented Interfaces:

Asn1BitMessageBuffer

public class Asn1OerDecodeBuffer
extends Asn1DecodeBitBuffer

This class handles the decoding of ASN.1 messages as specified in the Octet Encoding Rules (OER) as documented in the ITU-T X.696 standard.

Field Summary

Fields inherited from class com.objsys.asn1j.runtime.Asn1DecodeBitBuffer

mTraceHandler

Fields inherited from class com.objsys.asn1j.runtime.Asn1DecodeBuffer

mByteCount

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

context, mTypeCode

Constructor Summary

Constructors

Constructor and Description
Asn1OerDecodeBuffer(byte[] msgdata) This constructor creates a BER decode buffer object that references an encoded ASN.1 message.
Asn1OerDecodeBuffer(java.io.InputStream istream) This constructor creates a BER decode buffer object that references an encoded ASN.1 message.

Method Summary

Modifier and Type	Method and Description
int	decodeEnumValue() Decode enumerated value encoded in OER.
long	decodeIntSigned() Decode an integer value as a variable length, signed integer, including decoding the length, according to OER.
long	decodeIntSigned(int octets) Decode a signed integer value (2's complement form), of the given length.
long	decodeIntUnsigned() Decode an integer value as a variable length, unsigned integer, including decoding the length, according to OER.
long	decodeIntUnsigned(int octets) Decode an unsigned integer value (a binary integer, not 2's complement form), of the given length.
int	decodeLength() Decode OER length determinant and return the decoded value.
int	decodeQuantity() Decode an OER quantity (used for SEQUENCE-OF and SET-OF)
void	decodeTag(Asn1Tag tag) Decode a tag encoded in OER.
boolean	getCanonicalMode() Return true if canonical mode has been indicated by calling setCanonicalMode(true);
void	setCanonicalMode(boolean value) Turn canonical mode on/off.

Methods inherited from class com.objsys.asn1j.runtime.Asn1DecodeBitBuffer

binDump, binDump, byteAlign, decodeBit, decodeBitsToInt, decodeBitsToLong, decodeBitsToOctetArray, decodeBitsToOctetArray, getAvailableBits, getBitOffset, getBitOffsetInByte, getMsgBitCnt, getTraceHandler, hasMoreBits, mark, moveBitCursor, readByte, reset, setInputStream, skipBits

Methods inherited from class com.objsys.asn1j.runtime.Asn1DecodeBuffer

addCaptureBuffer, capture, decodeIntValue, decodeOIDContents, decodeOIDContentsBig, decodeRelOIDContents, decodeRelOIDContentsBig, getByteCount, getInputStream, getLazyOpenTypeDecode, hexDump, init, read, read, read, read2Bytes, read4Bytes, removeCaptureBuffer, setLazyOpenTypeDecode, skip, skipOIDContents, skipRelOIDContents

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, toString, wait, wait, wait

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

getInputStream

Constructor Detail

Asn1OerDecodeBuffer

public Asn1OerDecodeBuffer(byte[] msgdata)

This constructor creates a BER decode buffer object that references an encoded ASN.1 message.

Parameters:

msgdata - Byte array containing an encoded ASN.1 message.

Asn1OerDecodeBuffer

public Asn1OerDecodeBuffer(java.io.InputStream istream)

This constructor creates a BER decode buffer object that references an encoded ASN.1 message. In this case, the message is passed in using an InputStream object.

Parameters:

istream - Input stream containing an encoded ASN.1 message.

Method Detail

decodeEnumValue

public int decodeEnumValue()
                    throws java.io.IOException

Decode enumerated value encoded in OER.

Throws:

java.io.IOException

decodeLength

public int decodeLength()
                 throws java.io.IOException

Decode OER length determinant and return the decoded value.

Throws:

java.io.IOException

decodeIntSigned

public long decodeIntSigned(int octets)
                     throws java.io.IOException

Decode a signed integer value (2's complement form), of the given length. Note: this function will do sign-extension so that if a negative value was encoded in less than 8 bytes, the returned long will be that value (and not some positive value).

Parameters:

octets; - 0 < octets <= 8

Returns:

Throws:

java.io.IOException

decodeIntUnsigned

public long decodeIntUnsigned(int octets)
                       throws java.io.IOException

Decode an unsigned integer value (a binary integer, not 2's complement form), of the given length.

Parameters:

octets - The number of octets; 0 < octets <= 8

Returns:

Throws:

java.io.IOException

decodeIntSigned

public long decodeIntSigned()
                     throws java.io.IOException

Decode an integer value as a variable length, signed integer, including decoding the length, according to OER. This is used for integer values that have a lower bound less than -2^63, no lower bound, or a lower bound less than zero in combination with an upper bound greater than 2^63-1, or no upper bound. (In other words, it doesn't fit in a signed 64-bit integer.)

Throws:

java.io.IOException

decodeIntUnsigned

public long decodeIntUnsigned()
                       throws java.io.IOException

Decode an integer value as a variable length, unsigned integer, including decoding the length, according to OER. This is used for integer values that are constrained to be non-negative but which have no upper bound or an upper bound greater than 2^64 - 1.

Throws:

java.io.IOException

decodeQuantity

public int decodeQuantity()
                   throws java.io.IOException

Decode an OER quantity (used for SEQUENCE-OF and SET-OF)

Returns:

Throws:

java.io.IOException

decodeTag

public void decodeTag(Asn1Tag tag)
               throws java.io.IOException

Decode a tag encoded in OER.

Parameters:

tag - Object to decode into.

Throws:

java.io.IOException

getCanonicalMode

public boolean getCanonicalMode()

Return true if canonical mode has been indicated by calling setCanonicalMode(true);

Returns:

setCanonicalMode

public void setCanonicalMode(boolean value)

Turn canonical mode on/off. Turning canonical mode on acts as a signal to both generated code and runtime code that the user wants to enforce the canonical OER rules. It is not required to turn on canonical mode just because the encoding is canonical.