DerSet.cs :  » PDF » iTextSharp » Org » BouncyCastle » Asn1 » C# / CSharp Open Source

using System.IO;

namespace Org.BouncyCastle.Asn1{
  /**
   * A Der encoded set object
   */
  public class DerSet
    : Asn1Set
  {
    public static readonly DerSet Empty = new DerSet();

    public static DerSet FromVector(
      Asn1EncodableVector v)
    {
      return v.Count < 1 ? Empty : new DerSet(v);
    }

    internal static DerSet FromVector(
      Asn1EncodableVector  v,
      bool        needsSorting)
    {
      return v.Count < 1 ? Empty : new DerSet(v, needsSorting);
    }

    /**
     * create an empty set
     */
    public DerSet()
      : base(0)
    {
    }

    /**
     * @param obj - a single object that makes up the set.
     */
    public DerSet(
      Asn1Encodable obj)
      : base(1)
    {
      AddObject(obj);
    }

    public DerSet(
      params Asn1Encodable[] v)
      : base(v.Length)
    {
      foreach (Asn1Encodable o in v)
      {
        AddObject(o);
      }

      Sort();
    }

    /**
     * @param v - a vector of objects making up the set.
     */
    public DerSet(
      Asn1EncodableVector v)
      : this(v, true)
    {
    }

    internal DerSet(
      Asn1EncodableVector  v,
      bool        needsSorting)
      : base(v.Count)
    {
      foreach (Asn1Encodable o in v)
      {
        AddObject(o);
      }

      if (needsSorting)
      {
        Sort();
      }
    }

    /*
     * A note on the implementation:
     * <p>
     * As Der requires the constructed, definite-length model to
     * be used for structured types, this varies slightly from the
     * ASN.1 descriptions given. Rather than just outputing Set,
     * we also have to specify Constructed, and the objects length.
     */
    internal override void Encode(
      DerOutputStream derOut)
    {
      // TODO Intermediate buffer could be avoided if we could calculate expected length
      MemoryStream bOut = new MemoryStream();
      DerOutputStream dOut = new DerOutputStream(bOut);

      foreach (Asn1Encodable obj in this)
      {
        dOut.WriteObject(obj);
      }

      dOut.Close();

      byte[] bytes = bOut.ToArray();

      derOut.WriteEncoded(Asn1Tags.Set | Asn1Tags.Constructed, bytes);
    }
  }
}