Fix static readonly collections

1 files changed, 5 insertions, 5 deletions

diff --git a/crypto/src/tsp/TSPAlgorithms.cs b/crypto/src/tsp/TSPAlgorithms.cs
index 8d7e12ee4..eb5e89439 100644
--- a/crypto/src/tsp/TSPAlgorithms.cs
+++ b/crypto/src/tsp/TSPAlgorithms.cs
@@ -7,14 +7,14 @@ using Org.BouncyCastle.Asn1.Oiw;
 using Org.BouncyCastle.Asn1.Pkcs;
 using Org.BouncyCastle.Asn1.Rosstandart;
 using Org.BouncyCastle.Asn1.TeleTrust;
-using Org.BouncyCastle.Utilities;
+using Org.BouncyCastle.Utilities.Collections;
 
 namespace Org.BouncyCastle.Tsp
 {
 	/**
 	 * Recognised hash algorithms for the time stamp protocol.
 	 */
-	public abstract class TspAlgorithms
+	public static class TspAlgorithms
 	{
 		public static readonly string MD5 = PkcsObjectIdentifiers.MD5.Id;
 
@@ -35,15 +35,15 @@ namespace Org.BouncyCastle.Tsp
 
         public static readonly string SM3 = GMObjectIdentifiers.sm3.Id;
 
-        public static readonly List<string> Allowed;
+		public static readonly IList<string> Allowed;
 
 		static TspAlgorithms()
 		{
-			Allowed = new List<string>()
+			Allowed = CollectionUtilities.ReadOnly(new List<string>()
 			{
 				Gost3411, Gost3411_2012_256, Gost3411_2012_512, MD5, RipeMD128, RipeMD160, RipeMD256, Sha1, Sha224,
 				Sha256, Sha384, Sha512, SM3
-			};
+			});
 		}
 	}
 }