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

using System;
using System.Collections;

using Org.BouncyCastle.Asn1;

namespace Org.BouncyCastle.Asn1.Cms{
  public class ContentInfo
    : Asn1Encodable
  {
    private readonly DerObjectIdentifier  contentType;
    private readonly Asn1Encodable      content;

    public static ContentInfo GetInstance(
      object obj)
    {
      if (obj == null || obj is ContentInfo)
      {
        return (ContentInfo) obj;
      }

      if (obj is Asn1Sequence)
      {
        return new ContentInfo((Asn1Sequence) obj);
      }

      throw new ArgumentException("unknown object in factory: " + obj.GetType().Name);
    }

    private ContentInfo(
      Asn1Sequence seq)
    {
      if (seq.Count < 1 || seq.Count > 2)
        throw new ArgumentException("Bad sequence size: " + seq.Count, "seq");

      contentType = (DerObjectIdentifier) seq[0];

      if (seq.Count > 1)
      {
        Asn1TaggedObject optOcts = (Asn1TaggedObject) seq[1];
        if (optOcts.TagNo != 0)
          throw new ArgumentException("Tag number for 'content' must be 0");

        content = optOcts.GetObject();
      }
    }

    public ContentInfo(
      DerObjectIdentifier  contentType,
      Asn1Encodable    content)
    {
      this.contentType = contentType;
      this.content = content;
    }

    public DerObjectIdentifier ContentType
    {
      get { return contentType; }
    }

    public Asn1Encodable Content
    {
      get { return content; }
    }

    /**
     * Produce an object suitable for an Asn1OutputStream.
     * <pre>
     * ContentInfo ::= Sequence {
     *          contentType ContentType,
     *          content
     *          [0] EXPLICIT ANY DEFINED BY contentType OPTIONAL }
     * </pre>
     */
    public override Asn1Object ToAsn1Object()
    {
      Asn1EncodableVector v = new Asn1EncodableVector(contentType);

      if (content != null)
      {
        v.Add(new BerTaggedObject(0, content));
      }

      return new BerSequence(v);
    }
  }
}