/// <summary>
/// Checks whether an {@link InputStream} is in the Horrible
/// Property Set Format.
/// </summary>
/// <param name="stream">The {@link InputStream} To check. In order To
/// perform the check, the method Reads the first bytes from the
/// stream. After Reading, the stream is Reset To the position it
/// had before Reading. The {@link InputStream} must support the
/// {@link InputStream#mark} method.</param>
/// <returns>
/// <c>true</c> if the stream is a property Set
/// stream; otherwise, <c>false</c>.
/// </returns>
public static bool IsPropertySetStream(Stream stream)
{
ByteArrayInputStream dis = stream as ByteArrayInputStream;
/*
* Read at most this many bytes.
*/
int BUFFER_SIZE = 50;
/*
* Mark the current position in the stream so that we can
* Reset To this position if the stream does not contain a
* property Set.
*/
if (dis == null || !dis.MarkSupported())
{
throw new MarkUnsupportedException(stream.GetType().Name);
}
dis.Mark(BUFFER_SIZE);
/*
* Read a couple of bytes from the stream.
*/
byte[] buffer = new byte[BUFFER_SIZE];
int bytes =
stream.Read(buffer, 0,
(int)Math.Min(buffer.Length, dis.Available()));
bool isPropertySetStream =
IsPropertySetStream(buffer, 0, bytes);
stream.Seek(0, SeekOrigin.Begin);
dis.Reset();
return(isPropertySetStream);
}
