Package org.bouncycastle.asn1

Class ASN1Sequence

  • All Implemented Interfaces:
    ASN1Encodable, Encodable
    Direct Known Subclasses:
    BERSequence, DERSequence, DLSequence
    public abstract class ASN1Sequence
extends ASN1Primitive
    ASN.1 SEQUENCE and SEQUENCE OF constructs.

    DER form is always definite form length fields, while BER support uses indefinite form.

    X.690

    8: Basic encoding rules

    8.9 Encoding of a sequence value

    8.9.1 The encoding of a sequence value shall be constructed.

    8.9.2 The contents octets shall consist of the complete encoding of one data value from each of the types listed in the ASN.1 definition of the sequence type, in the order of their appearance in the definition, unless the type was referenced with the keyword OPTIONAL or the keyword DEFAULT.

    8.9.3 The encoding of a data value may, but need not, be present for a type which was referenced with the keyword OPTIONAL or the keyword DEFAULT. If present, it shall appear in the encoding at the point corresponding to the appearance of the type in the ASN.1 definition.

    8.10 Encoding of a sequence-of value

    8.10.1 The encoding of a sequence-of value shall be constructed.

    8.10.2 The contents octets shall consist of zero, one or more complete encodings of data values from the type listed in the ASN.1 definition.

    8.10.3 The order of the encodings of the data values shall be the same as the order of the data values in the sequence-of value to be encoded.

    9: Canonical encoding rules

    9.1 Length forms

    If the encoding is constructed, it shall employ the indefinite length form. If the encoding is primitive, it shall include the fewest length octets necessary. [Contrast with 8.1.3.2 b).]

    11: Restrictions on BER employed by both CER and DER

    11.5 Set and sequence components with default value

    The encoding of a set value or sequence value shall not include an encoding for any component value which is equal to its default value.

    • Field Detail

    • Constructor Detail

      • ASN1Sequence

        protected ASN1Sequence()
        Create an empty sequence

      • ASN1Sequence

        protected ASN1Sequence​(ASN1Encodable obj)
        Create a sequence containing one object
        Parameters:
        obj - the object to be put in the SEQUENCE.

      • ASN1Sequence

        protected ASN1Sequence​(ASN1EncodableVector v)
        Create a sequence containing a vector of objects.
        Parameters:
        v - the vector of objects to be put in the SEQUENCE

      • ASN1Sequence

        protected ASN1Sequence​(ASN1Encodable[] array)
        Create a sequence containing a vector of objects.

    • Method Detail

      • getInstance

        public static ASN1Sequence getInstance​(Object obj)
        Return an ASN1Sequence from the given object.
        Parameters:
        obj - the object we want converted.
        Returns:
        an ASN1Sequence instance, or null.
        Throws:
        IllegalArgumentException - if the object cannot be converted.

      • getInstance

        public static ASN1Sequence getInstance​(ASN1TaggedObject obj,
                                       boolean explicit)
        Return an ASN1 sequence from a tagged object. There is a special case here, if an object appears to have been explicitly tagged on reading but we were expecting it to be implicitly tagged in the normal course of events it indicates that we lost the surrounding sequence - so we need to add it back (this will happen if the tagged object is a sequence that contains other sequences). If you are dealing with implicitly tagged sequences you really should be using this method.
        Parameters:
        obj - the tagged object.
        explicit - true if the object is meant to be explicitly tagged, false otherwise.
        Returns:
        an ASN1Sequence instance.
        Throws:
        IllegalArgumentException - if the tagged object cannot be converted.

      • getObjectAt

        public ASN1Encodable getObjectAt​(int index)
        Return the object at the sequence position indicated by index.
        Parameters:
        index - the sequence number (starting at zero) of the object
        Returns:
        the object at the sequence position indicated by index.

      • size

        public int size()
        Return the number of objects in this sequence.
        Returns:
        the number of objects in this sequence.

      • hashCode

        public int hashCode()
        Description copied from class: Object
        Returns an integer hash code for this object. By contract, any two objects for which Object.equals(java.lang.Object) returns true must return the same hash code value. This means that subclasses of Object usually override both methods or neither method.

        Note that hash values must not change over time unless information used in equals comparisons also changes.

        See Writing a correct hashCode method if you intend implementing your own hashCode method.

        Specified by:
        hashCode in class ASN1Primitive
        Returns:
        this object's hash code.
        See Also:
        Object.equals(java.lang.Object)

      • toString

        public String toString()
        Description copied from class: Object
        Returns a string containing a concise, human-readable description of this object. Subclasses are encouraged to override this method and provide an implementation that takes into account the object's type and data. The default implementation is equivalent to the following expression: 
           getClass().getName() + '@' + Integer.toHexString(hashCode())

        See Writing a useful toString method if you intend implementing your own toString method.

        Overrides:
        toString in class Object
        Returns:
        a printable representation of this object.