org.spongycastle.asn1

Class ASN1Sequence

java.lang.Object

org.spongycastle.asn1.ASN1Object

org.spongycastle.asn1.ASN1Primitive

org.spongycastle.asn1.ASN1Sequence

All Implemented Interfaces:

java.lang.Iterable<ASN1Encodable>, ASN1Encodable, Encodable

Direct Known Subclasses:

BERSequence, DERSequence, DLSequence

public abstract class ASN1Sequence
extends ASN1Primitive
implements Iterable<ASN1Encodable>

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 Summary

Fields

Modifier and Type	Field and Description
protected java.util.Vector	seq

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	ASN1Sequence() Create an empty SEQUENCE
protected	ASN1Sequence(ASN1Encodable obj) Create a SEQUENCE containing one object.
protected	ASN1Sequence(ASN1Encodable[] array) Create a SEQUENCE containing an array of objects.
protected	ASN1Sequence(ASN1EncodableVector v) Create a SEQUENCE containing a vector of objects.

Method Summary

Modifier and Type	Method and Description
static ASN1Sequence	getInstance(ASN1TaggedObject obj, boolean explicit) Return an ASN1 SEQUENCE from a tagged object.
static ASN1Sequence	getInstance(java.lang.Object obj) Return an ASN1Sequence from the given object.
ASN1Encodable	getObjectAt(int index) Return the object at the sequence position indicated by index.
java.util.Enumeration	getObjects()
int	hashCode()
java.util.Iterator<ASN1Encodable>	iterator() Returns an iterator over a set of elements of type T.
ASN1SequenceParser	parser()
int	size() Return the number of objects in this sequence.
ASN1Encodable[]	toArray()
java.lang.String	toString()

Methods inherited from class org.spongycastle.asn1.ASN1Primitive

equals, fromByteArray, toASN1Primitive

Methods inherited from class org.spongycastle.asn1.ASN1Object

getEncoded, getEncoded, hasEncodedTagValue, toASN1Object

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface java.lang.Iterable

forEach, spliterator

Field Detail

seq

protected java.util.Vector seq

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 an array of objects.

Parameters:

array - the array of objects to be put in the SEQUENCE.

Method Detail

getInstance

public static ASN1Sequence getInstance(java.lang.Object obj)

Return an ASN1Sequence from the given object.

Parameters:

obj - the object we want converted.

Returns:

an ASN1Sequence instance, or null.

Throws:

java.lang.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:

java.lang.IllegalArgumentException - if the tagged object cannot be converted.

toArray

public ASN1Encodable[] toArray()

getObjects

public java.util.Enumeration getObjects()

parser

public ASN1SequenceParser parser()

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()

Specified by:

hashCode in class ASN1Primitive

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>

Returns:

an Iterator.