Package org.bouncycastle.asn1

Class ASN1Set

  • All Implemented Interfaces:
    java.lang.Iterable<ASN1Encodable>, ASN1Encodable, Encodable, Iterable<ASN1Encodable>
    Direct Known Subclasses:
    BERSet, DERSet, DLSet
    public abstract class ASN1Set
extends ASN1Primitive
implements Iterable<ASN1Encodable>
    ASN.1 SET and SET OF constructs.

    Note: This does not know which syntax the set is! (The difference: ordering of SET elements or not ordering.)

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

    The CER form support does not exist.

    X.690

    8: Basic encoding rules

    8.11 Encoding of a set value

    8.11.1 The encoding of a set value shall be constructed

    8.11.2 The contents octets shall consist of the complete encoding of a data value from each of the types listed in the ASN.1 definition of the set type, in an order chosen by the sender, unless the type was referenced with the keyword OPTIONAL or the keyword DEFAULT.

    8.11.3 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.

    NOTE — The order of data values in a set value is not significant, and places no constraints on the order during transfer

    8.12 Encoding of a set-of value

    8.12.1 The encoding of a set-of value shall be constructed.

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

    8.12.3 The order of data values need not be preserved by the encoding and subsequent decoding.

    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).]

    9.3 Set components

    The encodings of the component values of a set value shall appear in an order determined by their tags as specified in 8.6 of ITU-T Rec. X.680 | ISO/IEC 8824-1. Additionally, for the purposes of determining the order in which components are encoded when one or more component is an untagged choice type, each untagged choice type is ordered as though it has a tag equal to that of the smallest tag in that choice type or any untagged choice types nested within.

    10: Distinguished encoding rules

    10.1 Length forms

    The definite form of length encoding shall be used, encoded in the minimum number of octets. [Contrast with 8.1.3.2 b).]

    10.3 Set components

    The encodings of the component values of a set value shall appear in an order determined by their tags as specified in 8.6 of ITU-T Rec. X.680 | ISO/IEC 8824-1.
    NOTE — Where a component of the set is an untagged choice type, the location of that component in the ordering will depend on the tag of the choice component being encoded.

    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.

    11.6 Set-of components

    The encodings of the component values of a set-of value shall appear in ascending order, the encodings being compared as octet strings with the shorter components being padded at their trailing end with 0-octets.

    NOTE — The padding octets are for comparison purposes only and do not appear in the encodings.

    • Field Detail

      • isSorted

        protected final boolean isSorted

    • Constructor Detail

      • ASN1Set

        protected ASN1Set()

      • ASN1Set

        protected ASN1Set​(ASN1Encodable element)
        Create a SET containing one object
        Parameters:
        element - object to be added to the SET.

      • ASN1Set

        protected ASN1Set​(ASN1EncodableVector elementVector,
                  boolean doSort)
        Create a SET containing a vector of objects.
        Parameters:
        elementVector - a vector of objects to make up the SET.
        doSort - true if should be sorted DER style, false otherwise.

      • ASN1Set

        protected ASN1Set​(ASN1Encodable[] elements,
                  boolean doSort)
        Create a SET containing an array of objects.
        Parameters:
        elements - an array of objects to make up the SET.
        doSort - true if should be sorted DER style, false otherwise.

    • Method Detail

      • getInstance

        public static ASN1Set getInstance​(java.lang.Object obj)
        return an ASN1Set from the given object.
        Parameters:
        obj - the object we want converted.
        Returns:
        an ASN1Set instance, or null.
        Throws:
        java.lang.IllegalArgumentException - if the object cannot be converted.

      • getInstance

        public static ASN1Set getInstance​(ASN1TaggedObject taggedObject,
                                  boolean explicit)
        Return an ASN1 set 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 set - 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 sets you really should be using this method.
        Parameters:
        taggedObject - the tagged object.
        explicit - true if the object is meant to be explicitly tagged false otherwise.
        Returns:
        an ASN1Set instance.
        Throws:
        java.lang.IllegalArgumentException - if the tagged object cannot be converted.

      • getObjects

        public java.util.Enumeration getObjects()

      • getObjectAt

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

      • size

        public int size()
        return the number of objects in this set.
        Returns:
        the number of objects in this set.

      • toString

        public java.lang.String toString()
        Overrides:
        toString in class java.lang.Object

      • iterator

        public java.util.Iterator<ASN1Encodable> iterator()
        Description copied from interface: Iterable
        Returns an iterator over a set of elements of type T.
        Specified by:
        iterator in interface java.lang.Iterable<ASN1Encodable>
        Specified by:
        iterator in interface Iterable<ASN1Encodable>
        Returns:
        an Iterator.