Add TLVList builder pattern #205
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* Indicates throw BufferUnderflowException and IndexOutOfBoundsException by unpack and index ethods * Add missing jUnit test with BufferUnderflowException
The intention is to not promote the use of TLVMsg outside.
* make TLVMsg immutable No args constructor TLVMsg() creates tags with id 0x00 which is invalid as BER-TLV id and leads to produce of an incorrect TLV encoded bytes. Tag (TLVMsg) should be created when its id and value are known, e.g. from TLVList by createTag(int, byte[])
Add verification tag number in accordance with ISO/IEC 7816
Now is possible to create TLV engine that is not compliant with ISO/IEC
7816-4 BER-TLV rules, but it is usable in some situations e.g. parsing
Visa Base1 Datasets (which are fixed 2 bytes long) e.g.:
TLVList tl = TLVList.createInstance()
.fixedLengthSize(2)
.build()
After that using tl is as usual: unpack, append, pack, etc.
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Awesome work @demsey as usual! |
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Last commit implements builder pattern for
TLVList. So is possible parse/unpack TLV byte sequences that are not compliant with ISO/IEC 7816-4 BER-TLV rules. e.g: Visa Base1 Datasets (which are fixed 2 bytes long)After that using
tlis as usual: unpack, append, pack, etc.It is also possible to create
TLVListwith a fixed tag size:and even mixing them together.
e.g: when fixed length size 1 is used then length is encoded i 1 byte (0..255) unlike at ISO/IEC 7816-4 only (0..127)
The changes affected only
TLVListandTLVMsg(and corresponding jUnit test). They are never used in jPOS itself.API changes:
TLVMsg()TLVMsg.setTag(int)TLVMsg.setValue(byte[] value)At problems use just TLVList.append(tag, bytes)
TLVList.unpackto throws only one uncheckedIllegalArgumentExceptioninsteadISOExceptionand extra undocumentedBufferUnderflowExceptionTLVMsg(int, byte)- use TLVList.append(int, byte) instead.Most of these changes were necessary to ensure consistency in the situation of the availability of various types of
TLVList(which was previously not necessary)In addition 2427a9f introduces verification of created tag identifiers.
So now it is not possible to create an illegal (in ISO/IEC 7816-4 BER-TLV mode)
FF,00, '3F', etc. tags. Using them resulted in the creation of an unparsable byte sequence.