/**
* 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 implictly 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 <b>should</b>
* be using this method.
*
* @param obj the tagged object.
* @param explicit true if the object is meant to be explicitly tagged
* false otherwise.
* @exception IllegalArgumentException if the tagged object cannot
* be converted.
*/
public static ASN1Set getInstance(
ASN1TaggedObject obj,
bool explicitly)
{
if (explicitly)
{
if (!obj.isExplicit())
{
throw new ArgumentException("object implicit - explicit expected.");
}
return((ASN1Set)obj.getObject());
}
else
{
//
// constructed object which appears to be explicitly tagged
// and it's really implicit means we have to add the
// surrounding sequence.
//
if (obj.isExplicit())
{
ASN1Set set = new DERSet(obj.getObject());
return(set);
}
else
{
if (obj.getObject() is ASN1Set)
{
return((ASN1Set)obj.getObject());
}
//
// in this case the parser returns a sequence, convert it
// into a set.
//
ASN1EncodableVector v = new ASN1EncodableVector();
if (obj.getObject() is ASN1Sequence)
{
ASN1Sequence s = (ASN1Sequence)obj.getObject();
IEnumerator e = s.getObjects();
while (e.MoveNext())
{
v.add((ASN1Encodable)e.Current);
}
return(new DERSet(v));
}
}
}
throw new ArgumentException(
"unknown object in getInstanceFromTagged");
}
/**
* 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 implictly 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 <b>should</b>
* be using this method.
*
* @param obj the tagged object.
* @param explicit true if the object is meant to be explicitly tagged,
* false otherwise.
* @exception IllegalArgumentException if the tagged object cannot
* be converted.
*/
public static ASN1Sequence getInstance(
ASN1TaggedObject obj,
bool explicitly)
{
if (explicitly)
{
if (!obj.isExplicit())
{
throw new ArgumentException("object implicit - explicit expected.");
}
return((ASN1Sequence)obj.getObject());
}
else
{
//
// constructed object which appears to be explicitly tagged
// when it should be implicit means we have to add the
// surrounding sequence.
//
if (obj.isExplicit())
{
if (obj is BERTaggedObject)
{
return(new BERSequence(obj.getObject()));
}
else
{
return(new DERSequence(obj.getObject()));
}
}
else
{
if (obj.getObject() is ASN1Sequence)
{
return((ASN1Sequence)obj.getObject());
}
}
}
throw new ArgumentException(
"unknown object in getInstanceFromTagged");
}