• java.lang.Object
  

public final class APDUextends Object

Application Protocol Data Unit (APDU) is the communication format between the card and the off-card applications. The format of the APDU is defined in ISO specification 7816-4.

This class only supports messages which conform to the structure of command and response defined in ISO 7816-4. The behavior of messages which use proprietary structure of messages is undefined. This class optionally supports extended length fields but only when the currently selected applet implements the javacardx.apdu.ExtendedLength interface.

The APDU object is owned by the Java Card runtime environment. The APDU class maintains a byte array buffer which is used to transfer incoming APDU header and data bytes as well as outgoing data. The buffer length must be at least 133 bytes ( 5 bytes of header and 128 bytes of data ). The Java Card runtime environment must zero out the APDU buffer before each new message received from the CAD.

The Java Card runtime environment designates the APDU object as a temporary Java Card runtime environment Entry Point Object (See Runtime Environment Specification for the Java Card Platform, section 6.2.1 for details). A temporary Java Card runtime environment Entry Point Object can be accessed from any applet context. References to these temporary objects cannot be stored in class variables or instance variables or array components. The Java Card runtime environment similarly marks the APDU buffer as a global array (See Runtime Environment Specification for the Java Card Platform, section 6.2.2 for details). A global array can be accessed from any applet context. References to global arrays cannot be stored in class variables or instance variables or array components.

The applet receives the APDU instance to process from the Java Card runtime environment in the Applet.process(APDU) method, and the first five header bytes [ CLA, INS, P1, P2, P3 ] are available in the APDU buffer. (The header format is the ISO7816-4 defined 7 byte extended APDU format with a 3 byte Lc field when the Lc field in the incoming APDU header is 3 bytes long).

The APDU class API is designed to be transport protocol independent. In other words, applets can use the same APDU methods regardless of whether the underlying protocol in use is T=0 or T=1 (as defined in ISO 7816-3). The incoming APDU data size may be bigger than the APDU buffer size and may therefore need to be read in portions by the applet. Similarly, the outgoing response APDU data size may be bigger than the APDU buffer size and may need to be written in portions by the applet. The APDU class has methods to facilitate this.

For sending large byte arrays as response data, the APDU class provides a special method sendBytesLong() which manages the APDU buffer.

// The purpose of this example is to show most of the methods
 // in use and not to depict any particular APDU processing
 
 class MyApplet extends javacard.framework.Applet{
 // ...
 public void process(APDU apdu){
// ...
byte[] buffer = apdu.getBuffer();
byte cla = buffer[ISO7816.OFFSET_CLA];
byte ins = buffer[ISO7816.OFFSET_INS];
...
// assume this command has incoming data
// Lc tells us the incoming apdu command length
short bytesLeft = (short) (buffer[ISO7816.OFFSET_LC]  &  0x00FF);
if (bytesLeft  <  (short)55) ISOException.throwIt( ISO7816.SW_WRONG_LENGTH );
 
short readCount = apdu.setIncomingAndReceive();
while ( bytesLeft  >  0){
// process bytes in buffer[5] to buffer[readCount+4];
bytesLeft -= readCount;
readCount = apdu.receiveBytes ( ISO7816.OFFSET_CDATA );
}
//
//...
//
// Note that for a short response as in the case illustrated here
// the three APDU method calls shown : setOutgoing(),setOutgoingLength()  &  sendBytes()
// could be replaced by one APDU method call : setOutgoingAndSend().
 
// construct the reply APDU
short le = apdu.setOutgoing();
if (le  <  (short)2) ISOException.throwIt( ISO7816.SW_WRONG_LENGTH );
apdu.setOutgoingLength( (short)3 );
 
// build response data in apdu.buffer[ 0.. outCount-1 ];
buffer[0] = (byte)1; buffer[1] = (byte)2; buffer[3] = (byte)3;
apdu.sendBytes ( (short)0 , (short)3 );
// return good complete status 90 00
}
 // ...
 }
 

The APDU class also defines a set of STATE_.. constants which represent the various processing states of the APDU object based on the methods invoked and the state of the data transfers. The getCurrentState() method returns the current state.

Note that the state number assignments are ordered as follows: STATE_INITIAL < STATE_PARTIAL_INCOMING < STATE_FULL_INCOMING < STATE_OUTGOING < STATE_OUTGOING_LENGTH_KNOWN < STATE_PARTIAL_OUTGOING < STATE_FULL_OUTGOING.

The following are processing error states and have negative state number assignments : STATE_ERROR_NO_T0_GETRESPONSE, STATE_ERROR_T1_IFD_ABORT, STATE_ERROR_IO and STATE_ERROR_NO_T0_REISSUE. Note:

• The method descriptions use the ISO7816-4 notation for the various APDU I/O cases of input and output directions. For example - T=0 (Case 2S) protocol - refers to short length outbound only case using the T=0 protocol. The perspective of the notation used in the method descriptions is that of the card(ICC) as seen at the transport layer(TPDU). External transformations of the APDU I/O case may have occurred at the CAD and therefore not visible to the card.

See Also:APDUException , ISOException

public static final byte STATE_INITIAL

This is the state of a new APDU object when only the command header is valid.

See Also:Constant Field Values

public static final byte STATE_PARTIAL_INCOMING

This is the state of a APDU object when incoming data has partially been received.

See Also:Constant Field Values

public static final byte STATE_FULL_INCOMING

This is the state of a APDU object when all the incoming data been received.

See Also:Constant Field Values

public static final byte STATE_OUTGOING

This is the state of a new APDU object when data transfer mode is outbound but length is not yet known.

See Also:Constant Field Values

public static final byte STATE_OUTGOING_LENGTH_KNOWN

This is the state of a APDU object when data transfer mode is outbound and outbound length is known.

See Also:Constant Field Values

public static final byte STATE_PARTIAL_OUTGOING

This is the state of a APDU object when some outbound data has been transferred but not all.

See Also:Constant Field Values

public static final byte STATE_FULL_OUTGOING

This is the state of a APDU object when all outbound data has been transferred.

See Also:Constant Field Values

public static final byte STATE_ERROR_NO_T0_GETRESPONSE

This error state of a APDU object occurs when an APDUException with reason code APDUException.NO_T0_GETRESPONSE has been thrown.

See Also:Constant Field Values

public static final byte STATE_ERROR_T1_IFD_ABORT

This error state of a APDU object occurs when an APDUException with reason code APDUException.T1_IFD_ABORT has been thrown.

See Also:Constant Field Values

public static final byte STATE_ERROR_IO

This error state of a APDU object occurs when an APDUException with reason code APDUException.IO_ERROR has been thrown.

See Also:Constant Field Values

public static final byte STATE_ERROR_NO_T0_REISSUE

This error state of a APDU object occurs when an APDUException with reason code APDUException.NO_T0_REISSUE has been thrown.

See Also:Constant Field Values

public static final byte PROTOCOL_MEDIA_MASK

Media nibble mask in protocol byte

See Also:Constant Field Values

public static final byte PROTOCOL_TYPE_MASK

Type nibble mask in protocol byte

See Also:Constant Field Values

public static final byte PROTOCOL_T0

ISO 7816 transport protocol type T=0.

See Also:Constant Field Values

public static final byte PROTOCOL_T1

ISO 7816 transport protocol type T=1. This constant is also used to denote the T=CL variant for contactless cards defined in ISO14443-4.

See Also:Constant Field Values

public static final byte PROTOCOL_MEDIA_DEFAULT

Transport protocol Media - Contacted Asynchronous Half Duplex

See Also:Constant Field Values

public static final byte PROTOCOL_MEDIA_CONTACTLESS_TYPE_A

Transport protocol Media - Contactless Type A

See Also:Constant Field Values

public static final byte PROTOCOL_MEDIA_CONTACTLESS_TYPE_B

Transport protocol Media - Contactless Type B

See Also:Constant Field Values

public static final byte PROTOCOL_MEDIA_USB

Transport protocol Media - USB

See Also:Constant Field Values

public byte[] getBuffer()

Returns the APDU buffer byte array. Note:

• References to the APDU buffer byte array may be stored in local variables or method parameters.

• References to the APDU buffer byte array cannot be stored in class variables or instance variables or array components. See Runtime Environment Specification for the Java Card Platform, section 6.2.2 for details.

Returns:byte array containing the APDU buffer

public static short getInBlockSize()

Returns the configured incoming block size. In T=1 protocol, this corresponds to IFSC (information field size for ICC), the maximum size of incoming data blocks into the card. In T=0 protocol, this method returns 1. IFSC is defined in ISO 7816-3. This information may be used to ensure that there is enough space remaining in the APDU buffer when receiveBytes() is invoked. Note:

• On receiveBytes() the bOff param should account for this potential blocksize.

Returns:incoming block size setting

See Also:receiveBytes(short)

public static short getOutBlockSize()

Returns the configured outgoing block size. In T=1 protocol, this corresponds to IFSD (information field size for interface device), the maximum size of outgoing data blocks to the CAD. In T=0 protocol, this method returns 258 (accounts for 2 status bytes). IFSD is defined in ISO 7816-3. This information may be used prior to invoking the setOutgoingLength() method, to limit the length of outgoing messages when BLOCK CHAINING is not allowed. Note:

• On setOutgoingLength() the len param should account for this potential blocksize.

Returns:outgoing block size setting

See Also:setOutgoingLength(short)

public static byte getProtocol()

Returns the ISO 7816 transport protocol type, T=1 or T=0 in the low nibble and the transport media in the upper nibble in use.

Returns:the protocol media and type in progress Valid nibble codes are listed in PROTOCOL_* constants above. See PROTOCOL_T0 .

public byte getNAD()

Returns the Node Address byte (NAD) in T=1 protocol, and 0 in T=0 protocol. This may be used as additional information to maintain multiple contexts.

Returns:NAD transport byte as defined in ISO 7816-3

public short setOutgoing() throws APDUException

This method is used to set the data transfer direction to outbound and to obtain the expected length of response (Le). This method should only be called on a case 2 or case 4 command, otherwise erroneous behavior may result. Notes.

• On a case 4 command, the setIncomingAndReceive() must be invoked prior to calling this method. Otherwise, erroneous behavior may result in T=0 protocol.

• Any remaining incoming data will be discarded.

• In T=0 (Case 4S) protocol, this method will return 256 with normal semantics.

• In T=0 (Case 2E, 4S) protocol, this method will return 32767 when the currently selected applet implements the javacardx.apdu.ExtendedLength interface.

• In T=1 (Case 2E, 4E) protocol, this method will return 32767 when the Le field in the APDU command is 0x0000 and the currently selected applet implements the javacardx.apdu.ExtendedLength interface.

• This method sets the state of the APDU object to STATE_OUTGOING.

Returns:Le, the expected length of response

Throws: APDUException - with the following reason codes:

• APDUException.ILLEGAL_USE if this method, or setOutgoingNoChaining() method already invoked.

• APDUException.IO_ERROR on I/O error.

public short setOutgoingNoChaining() throws APDUException

This method is used to set the data transfer direction to outbound without using BLOCK CHAINING (See ISO 7816-3/4) and to obtain the expected length of response (Le). This method should be used in place of the setOutgoing() method by applets which need to be compatible with legacy CAD/terminals which do not support ISO 7816-3/4 defined block chaining. See Runtime Environment Specification for the Java Card Platform, section 9.4 for details. Notes.

• On a case 4 command, the setIncomingAndReceive() must be invoked prior to calling this method. Otherwise, erroneous behavior may result in T=0 protocol.

• Any remaining incoming data will be discarded.

• In T=0 (Case 4S) protocol, this method will return 256 with normal semantics.

• In T=0 (Case 2E, 4S) protocol, this method will return 256 when the currently selected applet implements the javacardx.apdu.ExtendedLength interface.

• When this method is used, the waitExtension() method cannot be used.

• In T=1 protocol, retransmission on error may be restricted.

• In T=0 protocol, the outbound transfer must be performed without using (ISO7816.SW_BYTES_REMAINING_00+count) response status chaining.

• In T=1 protocol, the outbound transfer must not set the More(M) Bit in the PCB of the I block. See ISO 7816-3.

• This method sets the state of the APDU object to STATE_OUTGOING.

Returns:Le, the expected length of response data

Throws: APDUException - with the following reason codes:

• APDUException.ILLEGAL_USE if this method, or setOutgoing() method already invoked.

• APDUException.IO_ERROR on I/O error

public void setOutgoingLength(short len) throws APDUException

Sets the actual length of response data. If a length of 0 is specified, no data will be output. Note:

• In T=0 (Case 2 & 4) protocol, the length is used by the Java Card runtime environment to prompt the CAD for GET RESPONSE commands.

• This method sets the state of the APDU object to STATE_OUTGOING_LENGTH_KNOWN.

Parameters:len - the length of response data

Throws: APDUException - with the following reason codes:

• APDUException.ILLEGAL_USE if setOutgoing() or setOutgoingNoChaining() not called or if setOutgoingAndSend() already invoked, or this method already invoked.

• APDUException.BAD_LENGTH if any one of the following is true:

• len is negative.

• len is greater than 256 and the currently selected applet does not implement the javacardx.apdu.ExtendedLength interface.

• T=0 protocol is in use, non BLOCK CHAINED data transfer is requested and len is greater than 256.

• T=1 protocol is in use, non BLOCK CHAINED data transfer is requested and len is greater than (IFSD-2), where IFSD is the Outgoing Block Size. The -2 accounts for the status bytes in T=1.

• APDUException.NO_T0_GETRESPONSE if T=0 protocol is in use and the CAD does not respond to (ISO7816.SW_BYTES_REMAINING_00+count) response status with GET RESPONSE command on the same origin logical channel number as that of the current APDU command.

• APDUException.NO_T0_REISSUE if T=0 protocol is in use and the CAD does not respond to (ISO7816.SW_CORRECT_LENGTH_00+count) response status by re-issuing same APDU command on the same origin logical channel number as that of the current APDU command with the corrected length.

• APDUException.IO_ERROR on I/O error.

See Also:getOutBlockSize()

public short receiveBytes(short bOff) throws APDUException

Gets as many data bytes as will fit without APDU buffer overflow, at the specified offset bOff. Gets all the remaining bytes if they fit. Notes:

• The space in the buffer must allow for incoming block size.

• In T=1 protocol, if all the remaining bytes do not fit in the buffer, this method may return less bytes than the maximum incoming block size (IFSC).

• In T=0 protocol, if all the remaining bytes do not fit in the buffer, this method may return less than a full buffer of bytes to optimize and reduce protocol overhead.

• In T=1 protocol, if this method throws an APDUException with T1_IFD_ABORT reason code, the Java Card runtime environment will restart APDU command processing using the newly received command. No more input data can be received. No output data can be transmitted. No error status response can be returned.

• This method sets the state of the APDU object to STATE_PARTIAL_INCOMING if all incoming bytes are not received.

• This method sets the state of the APDU object to STATE_FULL_INCOMING if all incoming bytes are received.

Parameters:bOff - the offset into APDU buffer

Returns:number of bytes read. Returns 0 if no bytes are available

Throws: APDUException - with the following reason codes:

• APDUException.ILLEGAL_USE if setIncomingAndReceive() not called or if setOutgoing() or setOutgoingNoChaining() previously invoked.

• APDUException.BUFFER_BOUNDS if not enough buffer space for incoming block size.

• APDUException.IO_ERROR on I/O error.

• APDUException.T1_IFD_ABORT if T=1 protocol is in use and the CAD sends in an ABORT S-Block command to abort the data transfer.

See Also:getInBlockSize()

public short setIncomingAndReceive() throws APDUException

This is the primary receive method. Calling this method indicates that this APDU has incoming data. This method gets as many bytes as will fit without buffer overflow in the APDU buffer following the header. It gets all the incoming bytes if they fit. This method should only be called on a case 3 or case 4 command, otherwise erroneous behavior may result. Notes:

• In T=0 ( Case 3 & 4 ) protocol, the P3 param is assumed to be Lc.

• Data is read into the buffer at offset 5 for normal APDU semantics.

• Data is read into the buffer at offset 7 for an extended length APDU (Case 3E/4E).

• In T=1 protocol, if all the incoming bytes do not fit in the buffer, this method may return less bytes than the maximum incoming block size (IFSC).

• In T=0 protocol, if all the incoming bytes do not fit in the buffer, this method may return less than a full buffer of bytes to optimize and reduce protocol overhead.

• This method sets the transfer direction to be inbound and calls receiveBytes(5) for normal semantics or receiveBytes(7) for extended semantics.

• This method may only be called once in a Applet.process() method.

• This method sets the state of the APDU object to STATE_PARTIAL_INCOMING if all incoming bytes are not received.

• This method sets the state of the APDU object to STATE_FULL_INCOMING if all incoming bytes are received.

Returns:number of data bytes read. The Le byte, if any, is not included in the count. Returns 0 if no bytes are available.

Throws: APDUException - with the following reason codes:

• APDUException.ILLEGAL_USE if setIncomingAndReceive() already invoked or if setOutgoing() or setOutgoingNoChaining() previously invoked.

• APDUException.IO_ERROR on I/O error.

• APDUException.T1_IFD_ABORT if T=1 protocol is in use and the CAD sends in an ABORT S-Block command to abort the data transfer.

See Also:getIncomingLength() , getOffsetCdata()

public void sendBytes(short bOff, short len) throws APDUException

Sends len more bytes from APDU buffer at specified offset bOff. If the last part of the response is being sent by the invocation of this method, the APDU buffer must not be altered. If the data is altered, incorrect output may be sent to the CAD. Requiring that the buffer not be altered allows the implementation to reduce protocol overhead by transmitting the last part of the response along with the status bytes. Notes:

• If setOutgoingNoChaining() was invoked, output block chaining must not be used.

• In T=0 protocol, if setOutgoingNoChaining() was invoked, Le bytes must be transmitted before (ISO7816.SW_BYTES_REMAINING_00+remaining bytes) response status is returned.

• In T=0 protocol, if this method throws an APDUException with NO_T0_GETRESPONSE or NO_T0_REISSUE reason code, the Java Card runtime environment will restart APDU command processing using the newly received command. No more output data can be transmitted. No error status response can be returned.

• In T=1 protocol, if this method throws an APDUException with T1_IFD_ABORT reason code, the Java Card runtime environment will restart APDU command processing using the newly received command. No more output data can be transmitted. No error status response can be returned.

• This method sets the state of the APDU object to STATE_PARTIAL_OUTGOING if all outgoing bytes have not been sent.

• This method sets the state of the APDU object to STATE_FULL_OUTGOING if all outgoing bytes have been sent.

Parameters:bOff - the offset into APDU buffer

len - the length of the data in bytes to send

Throws: APDUException - with the following reason codes:

• APDUException.ILLEGAL_USE if setOutgoingLength() not called or setOutgoingAndSend() previously invoked or response byte count exceeded or if APDUException.NO_T0_GETRESPONSE or APDUException.NO_T0_REISSUE or APDUException.T1_IFD_ABORT previously thrown.

• APDUException.BUFFER_BOUNDS if bOff is negative or len is negative or bOff+len exceeds the buffer size.

• APDUException.IO_ERROR on I/O error.

• APDUException.NO_T0_GETRESPONSE if T=0 protocol is in use and the CAD does not respond to (ISO7816.SW_BYTES_REMAINING_00+count) response status with GET RESPONSE command on the same origin logical channel number as that of the current APDU command.

• APDUException.NO_T0_REISSUE if T=0 protocol is in use and the CAD does not respond to (ISO7816.SW_CORRECT_LENGTH_00+count) response status by re-issuing same APDU command on the same origin logical channel number as that of the current APDU command with the corrected length.

• APDUException.T1_IFD_ABORT if T=1 protocol is in use and the CAD sends in an ABORT S-Block command to abort the data transfer.

See Also:setOutgoing() , setOutgoingNoChaining()

public void sendBytesLong(byte[] outData, short bOff, short len) throws APDUException , SecurityException

Sends len more bytes from outData byte array starting at specified offset bOff. If the last of the response is being sent by the invocation of this method, the APDU buffer must not be altered. If the data is altered, incorrect output may be sent to the CAD. Requiring that the buffer not be altered allows the implementation to reduce protocol overhead by transmitting the last part of the response along with the status bytes. The Java Card runtime environment may use the APDU buffer to send data to the CAD. Notes:

• If setOutgoingNoChaining() was invoked, output block chaining must not be used.

• In T=0 protocol, if setOutgoingNoChaining() was invoked, Le bytes must be transmitted before (ISO7816.SW_BYTES_REMAINING_00+remaining bytes) response status is returned.

• In T=0 protocol, if this method throws an APDUException with NO_T0_GETRESPONSE or NO_T0_REISSUE reason code, the Java Card runtime environment will restart APDU command processing using the newly received command. No more output data can be transmitted. No error status response can be returned.

• In T=1 protocol, if this method throws an APDUException with T1_IFD_ABORT reason code, the Java Card runtime environment will restart APDU command processing using the newly received command. No more output data can be transmitted. No error status response can be returned.

• This method sets the state of the APDU object to STATE_PARTIAL_OUTGOING if all outgoing bytes have not been sent.

• This method sets the state of the APDU object to STATE_FULL_OUTGOING if all outgoing bytes have been sent.

Parameters:outData - the source data byte array

bOff - the offset into OutData array

len - the byte length of the data to send

Throws: SecurityException - if the outData array is not accessible in the caller's context

APDUException - with the following reason codes:

• APDUException.ILLEGAL_USE if setOutgoingLength() not called or setOutgoingAndSend() previously invoked or response byte count exceeded or if APDUException.NO_T0_GETRESPONSE or APDUException.NO_T0_REISSUE or APDUException.NO_T0_REISSUE previously thrown.

• APDUException.IO_ERROR on I/O error.

• APDUException.NO_T0_GETRESPONSE if T=0 protocol is in use and CAD does not respond to (ISO7816.SW_BYTES_REMAINING_00+count) response status with GET RESPONSE command on the same origin logical channel number as that of the current APDU command.

• APDUException.T1_IFD_ABORT if T=1 protocol is in use and the CAD sends in an ABORT S-Block command to abort the data transfer.

See Also:setOutgoing() , setOutgoingNoChaining()

public void setOutgoingAndSend(short bOff, short len) throws APDUException

This is the “convenience” send method. It provides for the most efficient way to send a short response which fits in the buffer and needs the least protocol overhead. This method is a combination of setOutgoing(), setOutgoingLength( len ) followed by sendBytes ( bOff, len ). In addition, once this method is invoked, sendBytes() and sendBytesLong() methods cannot be invoked and the APDU buffer must not be altered. Sends len byte response from the APDU buffer starting at the specified offset bOff. Notes:

• No other APDU send methods can be invoked.

• The APDU buffer must not be altered. If the data is altered, incorrect output may be sent to the CAD.

• The actual data transmission may only take place on return from Applet.process()

• This method sets the state of the APDU object to STATE_FULL_OUTGOING.

Parameters:bOff - the offset into APDU buffer

len - the bytelength of the data to send

Throws: APDUException - with the following reason codes:

• APDUException.ILLEGAL_USE if setOutgoing() or setOutgoingAndSend() previously invoked.

• APDUException.IO_ERROR on I/O error.

• APDUException.BAD_LENGTH if len is negative or greater than 256 and the currently selected applet does not implement the javacardx.apdu.ExtendedLength interface.

public byte getCurrentState()

This method returns the current processing state of the APDU object. It is used by the BasicService class to help services collaborate in the processing of an incoming APDU command. Valid codes are listed in STATE_* constants above. See STATE_INITIAL .

Returns:the current processing state of the APDU

See Also:javacard.framework.service.BasicService

public static APDU getCurrentAPDU() throws SecurityException

This method is called during the Applet.process(APDU) method to obtain a reference to the current APDU object. This method can only be called in the context of the currently selected applet. Note:

• Do not call this method directly or indirectly from within a method invoked remotely via Java Card RMI method invocation from the client. The APDU object and APDU buffer are reserved for use by RMIService. Remote method parameter data may become corrupted.

Returns:the current APDU object being processed

Throws: SecurityException - if

• the current context is not the context of the currently selected applet instance or

• this method was not called, directly or indirectly, from the applet's process method (called directly by the Java Card runtime environment), or

• the method is called during applet installation or deletion.

public static byte[] getCurrentAPDUBuffer() throws SecurityException

This method is called during the Applet.process(APDU) method to obtain a reference to the current APDU buffer. This method can only be called in the context of the currently selected applet. Note:

• Do not call this method directly or indirectly from within a method invoked remotely via Java Card RMI method invocation from the client. The APDU object and APDU buffer are reserved for use by RMIService. Remote method parameter data may become corrupted.

Returns:the APDU buffer of the APDU object being processed

Throws: SecurityException - if

• the current context is not the context of the currently selected applet or

• this method was not called, directly or indirectly, from the applet's process method (called directly by the Java Card runtime environment), or

• the method is called during applet installation or deletion.

public static byte getCLAChannel()

Returns the logical channel number associated with the current APDU command based on the CLA byte. A number in the range 0-19 based on the CLA byte encoding is returned if the command contains logical channel encoding. If the command does not contain logical channel information, 0 is returned. See Runtime Environment Specification for the Java Card Platform, section 4.3 for encoding details.

Returns:logical channel number, if present, within the CLA byte, 0 otherwise

public static void waitExtension() throws APDUException

Requests additional processing time from CAD. The implementation should ensure that this method needs to be invoked only under unusual conditions requiring excessive processing times. Notes:

• In T=0 protocol, a NULL procedure byte is sent to reset the work waiting time (see ISO 7816-3).

• In T=1 protocol, the implementation needs to request the same T=0 protocol work waiting time quantum by sending a T=1 protocol request for wait time extension(see ISO 7816-3).

• If the implementation uses an automatic timer mechanism instead, this method may do nothing.

Throws: APDUException - with the following reason codes:

• APDUException.ILLEGAL_USE if setOutgoingNoChaining() previously invoked.

• APDUException.IO_ERROR on I/O error.

public boolean isCommandChainingCLA()

Returns whether the current APDU command is the first or part of a command chain. Bit b5 of the CLA byte if set, indicates that the APDU is the first or part of a chain of commands. See Runtime Environment Specification for the Java Card Platform, section 4.3 for encoding details.

Returns:true if this APDU is not the last APDU of a command chain, false otherwise.

Since:

2.2.2 

public boolean isSecureMessagingCLA()

Returns true if the encoding of the current APDU command based on the CLA byte indicates secure messaging. The secure messaging information is in bits (b4,b3) for commands with origin channel numbers 0-3, and in bit b6 for origin channel numbers 4-19. See Runtime Environment Specification for the Java Card Platform, section 4.3 for encoding details.

Returns:true if the secure messaging bit(s) is(are) nonzero, false otherwise

Since:

2.2.2 

public boolean isISOInterindustryCLA()

Returns whether the current APDU command CLA byte corresponds to an interindustry command as defined in ISO 7816-4:2005 specification. Bit b8 of the CLA byte if 0, indicates that the APDU is an interindustry command.

Returns:true if this APDU CLA byte corresponds to an interindustry command, false otherwise.

Since:

2.2.2 

public short getIncomingLength()

Returns the incoming data length(Lc). This method can be invoked whenever inbound data processing methods can be invoked during case 1, 3 or 4 processing. It is most useful for an extended length enabled applet to avoid parsing the variable length Lc format in the APDU header.

Returns:the incoming byte length indicated by the Lc field in the APDU header. Return 0 if no incoming data (Case 1)

Throws: APDUException - with the following reason codes:

• APDUException.ILLEGAL_USE if setIncomingAndReceive() not called or if setOutgoing() or setOutgoingNoChaining() previously invoked.Since:2.2.2

See Also:getOffsetCdata()

public short getOffsetCdata()

Returns the offset within the APDU buffer for incoming command data. This method can be invoked whenever inbound data processing methods can be invoked during case 1, 3 or 4 processing. It is most useful for an extended length enabled applet to avoid parsing the variable length Lc format in the APDU header.

Returns:the offset within the APDU buffer for incoming command data from the previous call to setIncomingAndReceive() method. The value returned is either 5 (Lc is 1 byte), or 7 (when Lc is 3 bytes)

Throws: APDUException - with the following reason codes:

• APDUException.ILLEGAL_USE if setIncomingAndReceive() not called or if setOutgoing() or setOutgoingNoChaining() previously invoked.Since:2.2.2

See Also:getIncomingLength()