Class BERTag

java.lang.Object
javacardx.framework.tlv.BERTag
Direct Known Subclasses:
ConstructedBERTag, PrimitiveBERTag
public abstract class BERTag extends Object
The abstract BERTag class encapsulates a BER TLV tag. The rules on the allowed encoding of the Tag field are based on the ASN.1 BER encoding rules of ISO/IEC 8825-1:2002.

The BERTag class and the subclasses ConstructedBERTag and PrimitiveBERTag, also provide static methods to parse or edit a BER Tag structure representation in a byte array.

Since:
2.2.2

  • Field Summary

    Fields
    Modifier and Type
    Field
    Description
    static final byte
    BER_TAG_CLASS_MASK_APPLICATION
    Constant for BER Tag Class Application
    static final byte
    BER_TAG_CLASS_MASK_CONTEXT_SPECIFIC
    Constant for BER Tag Class Context-Specific
    static final byte
    BER_TAG_CLASS_MASK_PRIVATE
    Constant for BER Tag Class Private
    static final byte
    BER_TAG_CLASS_MASK_UNIVERSAL
    Constant for BER Tag Class Universal
    static final boolean
    BER_TAG_TYPE_CONSTRUCTED
    Constant for constructed BER Tag type
    static final boolean
    BER_TAG_TYPE_PRIMITIVE
    Constant for primitive BER Tag type

  • Constructor Summary

    Constructors
    Modifier
    Constructor
    Description
    protected
    BERTag()
    Constructor creates an empty BERTLV Tag object capable of encapsulating a BER TLV Tag.

  • Method Summary

    Modifier and Type
    Method
    Description
    boolean
    equals(Object otherTag)
    Compares two Objects for equality.
    boolean
    equals(BERTag otherTag)
    Compares this BER Tag with another.
    static BERTag
    getInstance(byte[] bArray, short bOff)
    Create a BERTLV Tag object from the binary representation in the byte array.
    abstract void
    init(byte[] bArray, short bOff)
    Abstract init method.
    boolean
    isConstructed()
    Used to query if this BER tag structure is constructed
    static boolean
    isConstructed(byte[] berTagArray, short bOff)
    Returns the constructed flag part of the BER Tag from its representation in the specified byte array
    byte
    size()
    Returns the byte size required to represent this tag structure
    static byte
    size(byte[] berTagArray, short bOff)
    Returns the byte size required to represent the BER Tag from its representation in the specified byte array
    byte
    tagClass()
    Returns the tag class part of this BER Tag structure
    static byte
    tagClass(byte[] berTagArray, short bOff)
    Returns the tag class part of the BER Tag from its representation in the specified byte array
    short
    tagNumber()
    Returns the tag number part of this BER Tag structure
    static short
    tagNumber(byte[] berTagArray, short bOff)
    Returns the tag number part of the BER Tag from its representation in the specified byte array
    short
    toBytes(byte[] outBuf, short bOffset)
    Writes the representation of this BER tag structure to the byte array
    static short
    toBytes(short tagClass, boolean isConstructed, short tagNumber, byte[] outArray, short bOff)
    Writes the BER Tag bytes representing the specified tag class, constructed flag and the tag number as a BER Tag representation in the specified byte array
    static boolean
    verifyFormat(byte[] berTagArray, short bOff)
    Checks if the input data is a well-formed BER Tag representation

  • Field Details

    • BER_TAG_CLASS_MASK_UNIVERSAL

      public static final byte BER_TAG_CLASS_MASK_UNIVERSAL
      Constant for BER Tag Class Universal
      See Also:

    • BER_TAG_CLASS_MASK_APPLICATION

      public static final byte BER_TAG_CLASS_MASK_APPLICATION
      Constant for BER Tag Class Application
      See Also:

    • BER_TAG_CLASS_MASK_CONTEXT_SPECIFIC

      public static final byte BER_TAG_CLASS_MASK_CONTEXT_SPECIFIC
      Constant for BER Tag Class Context-Specific
      See Also:

    • BER_TAG_CLASS_MASK_PRIVATE

      public static final byte BER_TAG_CLASS_MASK_PRIVATE
      Constant for BER Tag Class Private
      See Also:

    • BER_TAG_TYPE_CONSTRUCTED

      public static final boolean BER_TAG_TYPE_CONSTRUCTED
      Constant for constructed BER Tag type
      See Also:

    • BER_TAG_TYPE_PRIMITIVE

      public static final boolean BER_TAG_TYPE_PRIMITIVE
      Constant for primitive BER Tag type
      See Also:

  • Constructor Details

    • BERTag

      protected BERTag()
      Constructor creates an empty BERTLV Tag object capable of encapsulating a BER TLV Tag. All implementations must support at least 3 byte Tags which can encode tag numbers up to 0x3FFF.

  • Method Details

    • init

      public abstract void init(byte[] bArray, short bOff) throws TLVException
      Abstract init method. (Re-)Initialize this BERTag object from the binary representation in the byte array. All implementations must support tag numbers up to 0x3FFF.
      Parameters:
      bArray - the byte array containing the binary representation
      bOff - the offset within bArray where the tag binary begins
      Throws:
      ArrayIndexOutOfBoundsException - if accessing the input array would cause access of data outside array bounds, or if the array offset parameter is negative
      NullPointerException - if bArray is null
      TLVException - with the following reason codes:
      • TLVException.ILLEGAL_SIZE if the tag number requested is larger than the supported maximum size
      • TLVException.MALFORMED_TAG if tag representation in the byte array is malformed

    • getInstance

      public static BERTag getInstance(byte[] bArray, short bOff) throws TLVException
      Create a BERTLV Tag object from the binary representation in the byte array. All implementations must support tag numbers up to 0x3FFF. Note that the returned BERTag must be cast to the correct subclass: PrimitiveBERTag or ConstructedBERTag to access their specialized API.
      Parameters:
      bArray - the byte array containing the binary representation
      bOff - the offset within bArray where the tag binary begins
      Returns:
      the BERTag object instance
      Throws:
      ArrayIndexOutOfBoundsException - if accessing the input array would cause access of data outside array bounds, or if the array offset parameter is negative
      NullPointerException - if bArray is null
      TLVException - with the following reason codes:
      • TLVException.ILLEGAL_SIZE if the tag number requested is larger than the supported maximum size
      • TLVException.MALFORMED_TAG if tag representation in the byte array is malformed.

    • size

      public byte size() throws TLVException
      Returns the byte size required to represent this tag structure
      Returns:
      size of BER Tag in bytes
      Throws:
      TLVException - with the following reason codes:
      • TLVException.TAG_SIZE_GREATER_THAN_127 if the size of the BER Tag is > 127.
      • TLVException.EMPTY_TAG if the BER Tag is empty.

    • toBytes

      public short toBytes(byte[] outBuf, short bOffset) throws TLVException
      Writes the representation of this BER tag structure to the byte array
      Parameters:
      outBuf - the byteArray where the BER tag is written
      bOffset - offset within outBuf where BER tag value starts
      Returns:
      size of BER Tag in bytes
      Throws:
      ArrayIndexOutOfBoundsException - if accessing the output array would cause access of data outside array bounds, or if the array offset parameter is negative
      NullPointerException - if outBuf is null
      TLVException - with the following reason codes:
      • TLVException.EMPTY_TAG if the BER Tag is empty.

    • tagNumber

      public short tagNumber() throws TLVException
      Returns the tag number part of this BER Tag structure
      Returns:
      the BER Tag tag number
      Throws:
      TLVException - with the following reason codes:
      • TLVException.TAG_NUMBER_GREATER_THAN_32767 if the tag number is > 32767.
      • TLVException.EMPTY_TAG if the BER Tag is empty.

    • isConstructed

      public boolean isConstructed()
      Used to query if this BER tag structure is constructed
      Returns:
      true if constructed, false if primitive
      Throws:
      TLVException - with the following reason codes:
      • TLVException.EMPTY_TAG if the BER Tag is empty.

    • tagClass

      public byte tagClass()
      Returns the tag class part of this BER Tag structure
      Returns:
      the BER Tag class. One of the BER_TAG_CLASS_MASK_*.. constants defined above, for example BER_TAG_CLASS_MASK_APPLICATION.
      Throws:
      TLVException - with the following reason codes:
      • TLVException.EMPTY_TAG if the BER Tag is empty.

    • equals

      public boolean equals(BERTag otherTag)
      Compares this BER Tag with another. Note that this method does not throw exceptions. If the parameter otherTag is null, the method returns false
      Parameters:
      otherTag - the reference BERTag with which to compare.
      Returns:
      true if the tag data encapsulated are equal, false otherwise

    • equals

      public boolean equals(Object otherTag)
      Compares two Objects for equality.

      The equals method implements an equivalence relation:

      • It is reflexive: for any reference value x, x.equals(x) should return true.
      • It is symmetric: for any reference values x and y, x.equals(y) should return true if and only if y.equals(x) returns true.
      • It is transitive: for any reference values x, y, and z, if x.equals(y) returns true and y.equals(z) returns true, then x.equals(z) should return true.
      • It is consistent: for any reference values x and y, multiple invocations of x.equals(y) consistently return true or consistently return false.
      • For any reference value x, x.equals(null) should return false.

      The equals method for class Object implements the most discriminating possible equivalence relation on objects; that is, for any reference values x and y, this method returns true if and only if x and y refer to the same object (x==y has the value true).

      Overrides:
      equals in class Object
      Parameters:
      otherTag - the reference object with which to compare.
      Returns:
      true if this object is the same as the obj argument; false otherwise.
      Since:
      3.0.5

    • toBytes

      public static short toBytes(short tagClass, boolean isConstructed, short tagNumber, byte[] outArray, short bOff)
      Writes the BER Tag bytes representing the specified tag class, constructed flag and the tag number as a BER Tag representation in the specified byte array
      Parameters:
      tagClass - encodes the tag class. Valid codes are the BER_TAG_CLASS_MASK_* constants defined above, for example BER_TAG_CLASS_MASK_APPLICATION.
      isConstructed - true if the tag is constructed, false if primitive
      tagNumber - is the tag number.
      outArray - output byte array
      bOff - offset within byte array containing first byte
      Returns:
      size of BER Tag output bytes
      Throws:
      ArrayIndexOutOfBoundsException - if accessing the output array would cause access of data outside array bounds, or if the array offset parameter is negative
      NullPointerException - if outArray is null
      TLVException - with the following reason codes:
      • TLVException.ILLEGAL_SIZE if the tag size is larger than the supported maximum size or 32767
      • TLVException.INVALID_PARAM if tagClass parameter is invalid or if the tagNumber parameter is negative

    • size

      public static byte size(byte[] berTagArray, short bOff) throws TLVException
      Returns the byte size required to represent the BER Tag from its representation in the specified byte array
      Parameters:
      berTagArray - input byte array containing the BER Tag representation
      bOff - offset within byte array containing first byte
      Returns:
      size of BER Tag in bytes
      Throws:
      ArrayIndexOutOfBoundsException - if accessing the input array would cause access of data outside array bounds, or if the array offset parameter is negative
      NullPointerException - if berTagArray is null
      TLVException - with the following reason codes:
      • TLVException.ILLEGAL_SIZE if the size of the BER Tag is greater than the maximum Tag size supported
      • TLVException.TAG_SIZE_GREATER_THAN_127 if the size of the BER Tag is > 127.
      • TLVException.MALFORMED_TAG if tag representation in the byte array is malformed

    • tagNumber

      public static short tagNumber(byte[] berTagArray, short bOff) throws TLVException
      Returns the tag number part of the BER Tag from its representation in the specified byte array
      Parameters:
      berTagArray - input byte array
      bOff - offset within byte array containing first byte
      Returns:
      the BER Tag tag number
      Throws:
      ArrayIndexOutOfBoundsException - if accessing the input array would cause access of data outside array bounds, or if the array offset parameter is negative
      NullPointerException - if berTagArray is null
      TLVException - with the following reason codes:
      • TLVException.ILLEGAL_SIZE if the size of the BER Tag is greater than the maximum Tag size supported
      • TLVException.TAG_NUMBER_GREATER_THAN_32767 if the tag number is > 32767.
      • TLVException.MALFORMED_TAG if tag representation in the byte array is malformed.

    • isConstructed

      public static boolean isConstructed(byte[] berTagArray, short bOff)
      Returns the constructed flag part of the BER Tag from its representation in the specified byte array
      Parameters:
      berTagArray - input byte array
      bOff - offset within byte array containing first byte
      Returns:
      true if constructed, false if primitive
      Throws:
      ArrayIndexOutOfBoundsException - if accessing the input array would cause access of data outside array bounds, or if the array offset parameter is negative
      NullPointerException - if berTagArray is null
      TLVException - with the following reason codes:
      • TLVException.MALFORMED_TAG if tag representation in the byte array is malformed.

    • tagClass

      public static byte tagClass(byte[] berTagArray, short bOff)
      Returns the tag class part of the BER Tag from its representation in the specified byte array
      Parameters:
      berTagArray - input byte array
      bOff - offset within byte array containing first byte
      Returns:
      the BER Tag class. One of the BER_TAG_CLASS_MASK_*.. constants defined above, for example BER_TAG_CLASS_MASK_APPLICATION.
      Throws:
      ArrayIndexOutOfBoundsException - if accessing the input array would cause access of data outside array bounds, or if the array offset parameter is negative
      NullPointerException - if berTagArray is null
      TLVException - with the following reason codes:
      • TLVException.MALFORMED_TAG if tag representation in the byte array is malformed.

    • verifyFormat

      public static boolean verifyFormat(byte[] berTagArray, short bOff)
      Checks if the input data is a well-formed BER Tag representation
      Parameters:
      berTagArray - input byte array
      bOff - offset within byte array containing first byte
      Returns:
      true if input data is a well formed BER Tag structure of tag size equal to or less than the supported maximum size, false otherwise
      Throws:
      ArrayIndexOutOfBoundsException - if accessing the input array would cause access of data outside array bounds, or if the array offset parameter is negative
      NullPointerException - if berTagArray is null