All product assemblies build without ccrewrite.exe now.

18 files changed, 52 insertions, 52 deletions

diff --git a/src/DotNetOpenAuth.OAuth2/OAuth2/ChannelElements/AccessToken.cs b/src/DotNetOpenAuth.OAuth2/OAuth2/ChannelElements/AccessToken.cs
index 6278828..a502962 100644
--- a/src/DotNetOpenAuth.OAuth2/OAuth2/ChannelElements/AccessToken.cs
+++ b/src/DotNetOpenAuth.OAuth2/OAuth2/ChannelElements/AccessToken.cs
@@ -28,7 +28,7 @@ namespace DotNetOpenAuth.OAuth2.ChannelElements {
 		/// <param name="authorization">The authorization to be described by the access token.</param>
 		/// <param name="lifetime">The lifetime of the access token.</param>
 		internal AccessToken(IAuthorizationDescription authorization, TimeSpan? lifetime) {
-			Contract.Requires<ArgumentNullException>(authorization != null);
+			Requires.NotNull(authorization, "authorization");
 
 			this.ClientIdentifier = authorization.ClientIdentifier;
 			this.UtcCreationDate = authorization.UtcIssued;
@@ -45,7 +45,7 @@ namespace DotNetOpenAuth.OAuth2.ChannelElements {
 		/// <param name="username">The username of the account that authorized this token.</param>
 		/// <param name="lifetime">The lifetime for this access token.</param>
 		internal AccessToken(string clientIdentifier, IEnumerable<string> scopes, string username, TimeSpan? lifetime) {
-			Contract.Requires<ArgumentException>(!String.IsNullOrEmpty(clientIdentifier));
+			Requires.NotNullOrEmpty(clientIdentifier, "clientIdentifier");
 
 			this.ClientIdentifier = clientIdentifier;
 			this.Scope.ResetContents(scopes);
diff --git a/src/DotNetOpenAuth.OAuth2/OAuth2/ChannelElements/AuthorizationCode.cs b/src/DotNetOpenAuth.OAuth2/OAuth2/ChannelElements/AuthorizationCode.cs
index 03732bb..6900b89 100644
--- a/src/DotNetOpenAuth.OAuth2/OAuth2/ChannelElements/AuthorizationCode.cs
+++ b/src/DotNetOpenAuth.OAuth2/OAuth2/ChannelElements/AuthorizationCode.cs
@@ -36,8 +36,8 @@ namespace DotNetOpenAuth.OAuth2.ChannelElements {
 		/// <param name="scopes">The authorized scopes.</param>
 		/// <param name="username">The name on the account that authorized access.</param>
 		internal AuthorizationCode(string clientIdentifier, Uri callback, IEnumerable<string> scopes, string username) {
-			Contract.Requires<ArgumentException>(!String.IsNullOrEmpty(clientIdentifier));
-			Contract.Requires<ArgumentNullException>(callback != null);
+			Requires.NotNullOrEmpty(clientIdentifier, "clientIdentifier");
+			Requires.NotNull(callback, "callback");
 
 			this.ClientIdentifier = clientIdentifier;
 			this.CallbackHash = CalculateCallbackHash(callback);
@@ -58,7 +58,7 @@ namespace DotNetOpenAuth.OAuth2.ChannelElements {
 		/// <param name="authorizationServer">The authorization server that will be serializing/deserializing this authorization code.  Must not be null.</param>
 		/// <returns>A DataBag formatter.</returns>
 		internal static IDataBagFormatter<AuthorizationCode> CreateFormatter(IAuthorizationServer authorizationServer) {
-			Contract.Requires<ArgumentNullException>(authorizationServer != null);
+			Requires.NotNull(authorizationServer, "authorizationServer");
 			Contract.Ensures(Contract.Result<IDataBagFormatter<AuthorizationCode>>() != null);
 
 			return new UriStyleMessageFormatter<AuthorizationCode>(
diff --git a/src/DotNetOpenAuth.OAuth2/OAuth2/ChannelElements/OAuth2AuthorizationServerChannel.cs b/src/DotNetOpenAuth.OAuth2/OAuth2/ChannelElements/OAuth2AuthorizationServerChannel.cs
index 888830e..0c31023 100644
--- a/src/DotNetOpenAuth.OAuth2/OAuth2/ChannelElements/OAuth2AuthorizationServerChannel.cs
+++ b/src/DotNetOpenAuth.OAuth2/OAuth2/ChannelElements/OAuth2AuthorizationServerChannel.cs
@@ -22,7 +22,7 @@ namespace DotNetOpenAuth.OAuth2.ChannelElements {
 		/// <param name="authorizationServer">The authorization server.</param>
 		protected internal OAuth2AuthorizationServerChannel(IAuthorizationServer authorizationServer)
 			: base(InitializeBindingElements(authorizationServer)) {
-			Contract.Requires<ArgumentNullException>(authorizationServer != null);
+			Requires.NotNull(authorizationServer, "authorizationServer");
 			this.AuthorizationServer = authorizationServer;
 		}
 
@@ -94,7 +94,7 @@ namespace DotNetOpenAuth.OAuth2.ChannelElements {
 		/// An array of binding elements used to initialize the channel.
 		/// </returns>
 		private static IChannelBindingElement[] InitializeBindingElements(IAuthorizationServer authorizationServer) {
-			Contract.Requires<ArgumentNullException>(authorizationServer != null);
+			Requires.NotNull(authorizationServer, "authorizationServer");
 			var bindingElements = new List<IChannelBindingElement>();
 
 			bindingElements.Add(new AuthServerAllFlowsBindingElement());
diff --git a/src/DotNetOpenAuth.OAuth2/OAuth2/ChannelElements/RefreshToken.cs b/src/DotNetOpenAuth.OAuth2/OAuth2/ChannelElements/RefreshToken.cs
index 9fe54c5..ee41957 100644
--- a/src/DotNetOpenAuth.OAuth2/OAuth2/ChannelElements/RefreshToken.cs
+++ b/src/DotNetOpenAuth.OAuth2/OAuth2/ChannelElements/RefreshToken.cs
@@ -31,7 +31,7 @@ namespace DotNetOpenAuth.OAuth2.ChannelElements {
 		/// </summary>
 		/// <param name="authorization">The authorization this refresh token should describe.</param>
 		internal RefreshToken(IAuthorizationDescription authorization) {
-			Contract.Requires<ArgumentNullException>(authorization != null);
+			Requires.NotNull(authorization, "authorization");
 
 			this.ClientIdentifier = authorization.ClientIdentifier;
 			this.UtcCreationDate = authorization.UtcIssued;
@@ -47,7 +47,7 @@ namespace DotNetOpenAuth.OAuth2.ChannelElements {
 		/// A DataBag formatter.  Never null.
 		/// </returns>
 		internal static IDataBagFormatter<RefreshToken> CreateFormatter(ICryptoKeyStore cryptoKeyStore) {
-			Contract.Requires<ArgumentNullException>(cryptoKeyStore != null);
+			Requires.NotNull(cryptoKeyStore, "cryptoKeyStore");
 			Contract.Ensures(Contract.Result<IDataBagFormatter<RefreshToken>>() != null);
 
 			return new UriStyleMessageFormatter<RefreshToken>(cryptoKeyStore, RefreshTokenKeyBucket, signed: true, encrypted: true);
diff --git a/src/DotNetOpenAuth.OAuth2/OAuth2/IAccessTokenAnalyzer.cs b/src/DotNetOpenAuth.OAuth2/OAuth2/IAccessTokenAnalyzer.cs
index 74b8ebb..0897090 100644
--- a/src/DotNetOpenAuth.OAuth2/OAuth2/IAccessTokenAnalyzer.cs
+++ b/src/DotNetOpenAuth.OAuth2/OAuth2/IAccessTokenAnalyzer.cs
@@ -54,8 +54,8 @@ namespace DotNetOpenAuth.OAuth2 {
 		/// A value indicating whether this access token is valid.
 		/// </returns>
 		bool IAccessTokenAnalyzer.TryValidateAccessToken(IDirectedProtocolMessage message, string accessToken, out string user, out HashSet<string> scope) {
-			Contract.Requires<ArgumentNullException>(message != null);
-			Contract.Requires<ArgumentException>(!String.IsNullOrEmpty(accessToken));
+			Requires.NotNull(message, "message");
+			Requires.NotNullOrEmpty(accessToken, "accessToken");
 			Contract.Ensures(Contract.Result<bool>() == (Contract.ValueAtReturn<string>(out user) != null));
 
 			throw new NotImplementedException();
diff --git a/src/DotNetOpenAuth.OAuth2/OAuth2/IAuthorizationServer.cs b/src/DotNetOpenAuth.OAuth2/OAuth2/IAuthorizationServer.cs
index 883f40c..6457f36 100644
--- a/src/DotNetOpenAuth.OAuth2/OAuth2/IAuthorizationServer.cs
+++ b/src/DotNetOpenAuth.OAuth2/OAuth2/IAuthorizationServer.cs
@@ -175,7 +175,7 @@ namespace DotNetOpenAuth.OAuth2 {
 		/// the resources to which access is being granted are sensitive.
 		/// </returns>
 		TimeSpan IAuthorizationServer.GetAccessTokenLifetime(IAccessTokenRequest accessTokenRequestMessage) {
-			Contract.Requires<ArgumentNullException>(accessTokenRequestMessage != null);
+			Requires.NotNull(accessTokenRequestMessage, "accessTokenRequestMessage");
 			throw new NotImplementedException();
 		}
 
@@ -191,7 +191,7 @@ namespace DotNetOpenAuth.OAuth2 {
 		/// The caller is responsible to dispose of this value.
 		/// </returns>
 		RSACryptoServiceProvider IAuthorizationServer.GetResourceServerEncryptionKey(IAccessTokenRequest accessTokenRequestMessage) {
-			Contract.Requires<ArgumentNullException>(accessTokenRequestMessage != null);
+			Requires.NotNull(accessTokenRequestMessage, "accessTokenRequestMessage");
 			Contract.Ensures(Contract.Result<RSACryptoServiceProvider>() != null);
 			throw new NotImplementedException();
 		}
@@ -203,7 +203,7 @@ namespace DotNetOpenAuth.OAuth2 {
 		/// <returns>The client registration.  Never null.</returns>
 		/// <exception cref="ArgumentException">Thrown when no client with the given identifier is registered with this authorization server.</exception>
 		IConsumerDescription IAuthorizationServer.GetClient(string clientIdentifier) {
-			Contract.Requires<ArgumentException>(!String.IsNullOrEmpty(clientIdentifier));
+			Requires.NotNullOrEmpty(clientIdentifier, "clientIdentifier");
 			Contract.Ensures(Contract.Result<IConsumerDescription>() != null);
 			throw new NotImplementedException();
 		}
@@ -231,7 +231,7 @@ namespace DotNetOpenAuth.OAuth2 {
 		/// account or piece of hardware in which the tokens were stored. </para>
 		/// </remarks>
 		bool IAuthorizationServer.IsAuthorizationValid(IAuthorizationDescription authorization) {
-			Contract.Requires<ArgumentNullException>(authorization != null);
+			Requires.NotNull(authorization, "authorization");
 			throw new NotImplementedException();
 		}
 	}
diff --git a/src/DotNetOpenAuth.OAuth2/OAuth2/IClientAuthorizationTracker.cs b/src/DotNetOpenAuth.OAuth2/OAuth2/IClientAuthorizationTracker.cs
index 97294e6..4529cef 100644
--- a/src/DotNetOpenAuth.OAuth2/OAuth2/IClientAuthorizationTracker.cs
+++ b/src/DotNetOpenAuth.OAuth2/OAuth2/IClientAuthorizationTracker.cs
@@ -44,7 +44,7 @@ namespace DotNetOpenAuth.OAuth2 {
 		/// The authorization state; may be <c>null</c> if no authorization state matches.
 		/// </returns>
 		IAuthorizationState IClientAuthorizationTracker.GetAuthorizationState(Uri callbackUrl, string clientState) {
-			Contract.Requires<ArgumentNullException>(callbackUrl != null);
+			Requires.NotNull(callbackUrl, "callbackUrl");
 			throw new NotImplementedException();
 		}
 
diff --git a/src/DotNetOpenAuth.OAuth2/OAuth2/IConsumerDescription.cs b/src/DotNetOpenAuth.OAuth2/OAuth2/IConsumerDescription.cs
index 14f3523..cf07dc6 100644
--- a/src/DotNetOpenAuth.OAuth2/OAuth2/IConsumerDescription.cs
+++ b/src/DotNetOpenAuth.OAuth2/OAuth2/IConsumerDescription.cs
@@ -91,8 +91,8 @@ namespace DotNetOpenAuth.OAuth2 {
 		///   <c>true</c> if the callback is allowed; otherwise, <c>false</c>.
 		/// </returns>
 		bool IConsumerDescription.IsCallbackAllowed(Uri callback) {
-			Contract.Requires<ArgumentNullException>(callback != null);
-			Contract.Requires<ArgumentException>(callback.IsAbsoluteUri);
+			Requires.NotNull(callback, "callback");
+			Requires.True(callback.IsAbsoluteUri, "callback");
 			throw new NotImplementedException();
 		}
 
diff --git a/src/DotNetOpenAuth.OAuth2/OAuth2/Messages/AccessTokenAuthorizationCodeRequest.cs b/src/DotNetOpenAuth.OAuth2/OAuth2/Messages/AccessTokenAuthorizationCodeRequest.cs
index 22dad1d..f3dad87 100644
--- a/src/DotNetOpenAuth.OAuth2/OAuth2/Messages/AccessTokenAuthorizationCodeRequest.cs
+++ b/src/DotNetOpenAuth.OAuth2/OAuth2/Messages/AccessTokenAuthorizationCodeRequest.cs
@@ -34,7 +34,7 @@ namespace DotNetOpenAuth.OAuth2.Messages {
 		/// <param name="authorizationServer">The authorization server.</param>
 		internal AccessTokenAuthorizationCodeRequest(AuthorizationServerDescription authorizationServer)
 			: this(authorizationServer.TokenEndpoint, authorizationServer.Version) {
-			Contract.Requires<ArgumentNullException>(authorizationServer != null);
+			Requires.NotNull(authorizationServer, "authorizationServer");
 		}
 
 		/// <summary>
diff --git a/src/DotNetOpenAuth.OAuth2/OAuth2/Messages/EndUserAuthorizationFailedResponse.cs b/src/DotNetOpenAuth.OAuth2/OAuth2/Messages/EndUserAuthorizationFailedResponse.cs
index 5497e1b..ecf3254 100644
--- a/src/DotNetOpenAuth.OAuth2/OAuth2/Messages/EndUserAuthorizationFailedResponse.cs
+++ b/src/DotNetOpenAuth.OAuth2/OAuth2/Messages/EndUserAuthorizationFailedResponse.cs
@@ -24,8 +24,8 @@ namespace DotNetOpenAuth.OAuth2.Messages {
 		/// <param name="version">The protocol version.</param>
 		internal EndUserAuthorizationFailedResponse(Uri clientCallback, Version version)
 			: base(version, MessageTransport.Indirect, clientCallback) {
-			Contract.Requires<ArgumentNullException>(version != null);
-			Contract.Requires<ArgumentNullException>(clientCallback != null);
+			Requires.NotNull(version, "version");
+			Requires.NotNull(clientCallback, "clientCallback");
 		}
 
 		/// <summary>
@@ -35,7 +35,7 @@ namespace DotNetOpenAuth.OAuth2.Messages {
 		/// <param name="request">The authorization request from the user agent on behalf of the client.</param>
 		internal EndUserAuthorizationFailedResponse(Uri clientCallback, EndUserAuthorizationRequest request)
 			: base(((IProtocolMessage)request).Version, MessageTransport.Indirect, clientCallback) {
-			Contract.Requires<ArgumentNullException>(request != null);
+			Requires.NotNull(request, "request");
 			((IMessageWithClientState)this).ClientState = request.ClientState;
 		}
 
diff --git a/src/DotNetOpenAuth.OAuth2/OAuth2/Messages/EndUserAuthorizationRequest.cs b/src/DotNetOpenAuth.OAuth2/OAuth2/Messages/EndUserAuthorizationRequest.cs
index 1cb2bab..2455406 100644
--- a/src/DotNetOpenAuth.OAuth2/OAuth2/Messages/EndUserAuthorizationRequest.cs
+++ b/src/DotNetOpenAuth.OAuth2/OAuth2/Messages/EndUserAuthorizationRequest.cs
@@ -27,8 +27,8 @@ namespace DotNetOpenAuth.OAuth2.Messages {
 		/// <param name="version">The protocol version.</param>
 		internal EndUserAuthorizationRequest(Uri authorizationEndpoint, Version version)
 			: base(version, MessageTransport.Indirect, authorizationEndpoint) {
-			Contract.Requires<ArgumentNullException>(authorizationEndpoint != null);
-			Contract.Requires<ArgumentNullException>(version != null);
+			Requires.NotNull(authorizationEndpoint, "authorizationEndpoint");
+			Requires.NotNull(version, "version");
 			this.HttpMethods = HttpDeliveryMethods.GetRequest | HttpDeliveryMethods.PostRequest;
 			this.Scope = new HashSet<string>(OAuthUtilities.ScopeStringComparer);
 			this.ResponseType = EndUserAuthorizationResponseType.AuthorizationCode;
@@ -40,9 +40,9 @@ namespace DotNetOpenAuth.OAuth2.Messages {
 		/// <param name="authorizationServer">The authorization server.</param>
 		internal EndUserAuthorizationRequest(AuthorizationServerDescription authorizationServer)
 			: this(authorizationServer.AuthorizationEndpoint, authorizationServer.Version) {
-			Contract.Requires<ArgumentNullException>(authorizationServer != null);
-			Contract.Requires<ArgumentException>(authorizationServer.Version != null);
-			Contract.Requires<ArgumentException>(authorizationServer.AuthorizationEndpoint != null);
+			Requires.NotNull(authorizationServer, "authorizationServer");
+			Requires.True(authorizationServer.Version != null, "authorizationServer");
+			Requires.True(authorizationServer.AuthorizationEndpoint != null, "authorizationServer");
 		}
 
 		/// <summary>
diff --git a/src/DotNetOpenAuth.OAuth2/OAuth2/Messages/EndUserAuthorizationSuccessAccessTokenResponse.cs b/src/DotNetOpenAuth.OAuth2/OAuth2/Messages/EndUserAuthorizationSuccessAccessTokenResponse.cs
index c9373eb..b82b1da 100644
--- a/src/DotNetOpenAuth.OAuth2/OAuth2/Messages/EndUserAuthorizationSuccessAccessTokenResponse.cs
+++ b/src/DotNetOpenAuth.OAuth2/OAuth2/Messages/EndUserAuthorizationSuccessAccessTokenResponse.cs
@@ -27,8 +27,8 @@ namespace DotNetOpenAuth.OAuth2.Messages {
 		/// <param name="version">The protocol version.</param>
 		internal EndUserAuthorizationSuccessAccessTokenResponse(Uri clientCallback, Version version)
 			: base(clientCallback, version) {
-			Contract.Requires<ArgumentNullException>(version != null);
-			Contract.Requires<ArgumentNullException>(clientCallback != null);
+			Requires.NotNull(version, "version");
+			Requires.NotNull(clientCallback, "clientCallback");
 			this.TokenType = Protocol.AccessTokenTypes.Bearer;
 		}
 
@@ -39,8 +39,8 @@ namespace DotNetOpenAuth.OAuth2.Messages {
 		/// <param name="request">The authorization request from the user agent on behalf of the client.</param>
 		internal EndUserAuthorizationSuccessAccessTokenResponse(Uri clientCallback, EndUserAuthorizationRequest request)
 			: base(clientCallback, request) {
-			Contract.Requires<ArgumentNullException>(clientCallback != null);
-			Contract.Requires<ArgumentNullException>(request != null);
+			Requires.NotNull(clientCallback, "clientCallback");
+			Requires.NotNull(request, "request");
 			((IMessageWithClientState)this).ClientState = request.ClientState;
 			this.TokenType = Protocol.AccessTokenTypes.Bearer;
 		}
diff --git a/src/DotNetOpenAuth.OAuth2/OAuth2/Messages/EndUserAuthorizationSuccessAuthCodeResponse.cs b/src/DotNetOpenAuth.OAuth2/OAuth2/Messages/EndUserAuthorizationSuccessAuthCodeResponse.cs
index 65965ef..ac7f392 100644
--- a/src/DotNetOpenAuth.OAuth2/OAuth2/Messages/EndUserAuthorizationSuccessAuthCodeResponse.cs
+++ b/src/DotNetOpenAuth.OAuth2/OAuth2/Messages/EndUserAuthorizationSuccessAuthCodeResponse.cs
@@ -24,8 +24,8 @@ namespace DotNetOpenAuth.OAuth2.Messages {
 		/// <param name="version">The protocol version.</param>
 		internal EndUserAuthorizationSuccessAuthCodeResponse(Uri clientCallback, Version version)
 			: base(clientCallback, version) {
-			Contract.Requires<ArgumentNullException>(version != null);
-			Contract.Requires<ArgumentNullException>(clientCallback != null);
+			Requires.NotNull(version, "version");
+			Requires.NotNull(clientCallback, "clientCallback");
 		}
 
 		/// <summary>
@@ -35,8 +35,8 @@ namespace DotNetOpenAuth.OAuth2.Messages {
 		/// <param name="request">The authorization request from the user agent on behalf of the client.</param>
 		internal EndUserAuthorizationSuccessAuthCodeResponse(Uri clientCallback, EndUserAuthorizationRequest request)
 			: base(clientCallback, request) {
-			Contract.Requires<ArgumentNullException>(clientCallback != null);
-			Contract.Requires<ArgumentNullException>(request != null);
+			Requires.NotNull(clientCallback, "clientCallback");
+			Requires.NotNull(request, "request");
 			((IMessageWithClientState)this).ClientState = request.ClientState;
 		}
 
diff --git a/src/DotNetOpenAuth.OAuth2/OAuth2/Messages/EndUserAuthorizationSuccessResponseBase.cs b/src/DotNetOpenAuth.OAuth2/OAuth2/Messages/EndUserAuthorizationSuccessResponseBase.cs
index d3c32e8..ff52743 100644
--- a/src/DotNetOpenAuth.OAuth2/OAuth2/Messages/EndUserAuthorizationSuccessResponseBase.cs
+++ b/src/DotNetOpenAuth.OAuth2/OAuth2/Messages/EndUserAuthorizationSuccessResponseBase.cs
@@ -26,8 +26,8 @@ namespace DotNetOpenAuth.OAuth2.Messages {
 		/// <param name="version">The protocol version.</param>
 		internal EndUserAuthorizationSuccessResponseBase(Uri clientCallback, Version version)
 			: base(version, MessageTransport.Indirect, clientCallback) {
-			Contract.Requires<ArgumentNullException>(version != null);
-			Contract.Requires<ArgumentNullException>(clientCallback != null);
+			Requires.NotNull(version, "version");
+			Requires.NotNull(clientCallback, "clientCallback");
 			this.Scope = new HashSet<string>(OAuthUtilities.ScopeStringComparer);
 		}
 
@@ -38,8 +38,8 @@ namespace DotNetOpenAuth.OAuth2.Messages {
 		/// <param name="request">The authorization request from the user agent on behalf of the client.</param>
 		internal EndUserAuthorizationSuccessResponseBase(Uri clientCallback, EndUserAuthorizationRequest request)
 			: base(request, clientCallback) {
-			Contract.Requires<ArgumentNullException>(clientCallback != null);
-			Contract.Requires<ArgumentNullException>(request != null);
+			Requires.NotNull(clientCallback, "clientCallback");
+			Requires.NotNull(request, "request");
 			((IMessageWithClientState)this).ClientState = request.ClientState;
 			this.Scope = new HashSet<string>(OAuthUtilities.ScopeStringComparer);
 			this.Scope.ResetContents(request.Scope);
diff --git a/src/DotNetOpenAuth.OAuth2/OAuth2/Messages/MessageBase.cs b/src/DotNetOpenAuth.OAuth2/OAuth2/Messages/MessageBase.cs
index e390d6e..c5e438f 100644
--- a/src/DotNetOpenAuth.OAuth2/OAuth2/Messages/MessageBase.cs
+++ b/src/DotNetOpenAuth.OAuth2/OAuth2/Messages/MessageBase.cs
@@ -42,7 +42,7 @@ namespace DotNetOpenAuth.OAuth2.Messages {
 		/// </summary>
 		/// <param name="version">The version.</param>
 		protected MessageBase(Version version) {
-			Contract.Requires<ArgumentNullException>(version != null);
+			Requires.NotNull(version, "version");
 			this.messageTransport = MessageTransport.Direct;
 			this.version = version;
 			this.HttpMethods = HttpDeliveryMethods.GetRequest;
@@ -54,7 +54,7 @@ namespace DotNetOpenAuth.OAuth2.Messages {
 		/// <param name="request">The originating request.</param>
 		/// <param name="recipient">The recipient of the directed message.  Null if not applicable.</param>
 		protected MessageBase(IDirectedProtocolMessage request, Uri recipient = null) {
-			Contract.Requires<ArgumentNullException>(request != null);
+			Requires.NotNull(request, "request");
 			this.originatingRequest = request;
 			this.messageTransport = request.Transport;
 			this.version = request.Version;
@@ -70,8 +70,8 @@ namespace DotNetOpenAuth.OAuth2.Messages {
 		/// <param name="messageTransport">The message transport.</param>
 		/// <param name="recipient">The recipient.</param>
 		protected MessageBase(Version version, MessageTransport messageTransport, Uri recipient) {
-			Contract.Requires<ArgumentNullException>(version != null);
-			Contract.Requires<ArgumentNullException>(recipient != null);
+			Requires.NotNull(version, "version");
+			Requires.NotNull(recipient, "recipient");
 
 			this.version = version;
 			this.messageTransport = messageTransport;
diff --git a/src/DotNetOpenAuth.OAuth2/OAuth2/Messages/UnauthorizedResponse.cs b/src/DotNetOpenAuth.OAuth2/OAuth2/Messages/UnauthorizedResponse.cs
index d79c00b..529fab2 100644
--- a/src/DotNetOpenAuth.OAuth2/OAuth2/Messages/UnauthorizedResponse.cs
+++ b/src/DotNetOpenAuth.OAuth2/OAuth2/Messages/UnauthorizedResponse.cs
@@ -23,7 +23,7 @@ namespace DotNetOpenAuth.OAuth2.Messages {
 		/// <param name="version">The protocol version.</param>
 		internal UnauthorizedResponse(ProtocolException exception, Version version = null)
 			: base(version ?? Protocol.Default.Version) {
-			Contract.Requires<ArgumentNullException>(exception != null);
+			Requires.NotNull(exception, "exception");
 			this.ErrorMessage = exception.Message;
 		}
 
@@ -43,7 +43,7 @@ namespace DotNetOpenAuth.OAuth2.Messages {
 		/// <param name="exception">The exception.</param>
 		internal UnauthorizedResponse(IDirectedProtocolMessage request, ProtocolException exception)
 			: this(request) {
-			Contract.Requires<ArgumentNullException>(exception != null);
+			Requires.NotNull(exception, "exception");
 			this.ErrorMessage = exception.Message;
 		}
 
diff --git a/src/DotNetOpenAuth.OAuth2/OAuth2/OAuthUtilities.cs b/src/DotNetOpenAuth.OAuth2/OAuth2/OAuthUtilities.cs
index c2b2f5f..1ae3701 100644
--- a/src/DotNetOpenAuth.OAuth2/OAuth2/OAuthUtilities.cs
+++ b/src/DotNetOpenAuth.OAuth2/OAuth2/OAuthUtilities.cs
@@ -81,7 +81,7 @@ namespace DotNetOpenAuth.OAuth2 {
 		/// <param name="scopes">The scopes to serialize.</param>
 		/// <returns>A space-delimited list.</returns>
 		public static string JoinScopes(HashSet<string> scopes) {
-			Contract.Requires<ArgumentNullException>(scopes != null);
+			Requires.NotNull(scopes, "scopes");
 			return string.Join(" ", scopes.ToArray());
 		}
 
@@ -91,8 +91,8 @@ namespace DotNetOpenAuth.OAuth2 {
 		/// <param name="request">The request to authorize.</param>
 		/// <param name="accessToken">The access token previously obtained from the Authorization Server.</param>
 		internal static void AuthorizeWithBearerToken(this HttpWebRequest request, string accessToken) {
-			Contract.Requires<ArgumentNullException>(request != null);
-			Contract.Requires<ArgumentException>(!string.IsNullOrEmpty(accessToken));
+			Requires.NotNull(request, "request");
+			Requires.NotNullOrEmpty(accessToken, "accessToken");
 			ErrorUtilities.VerifyProtocol(accessToken.All(ch => accessTokenAuthorizationHeaderAllowedCharacters.IndexOf(ch) >= 0), "The access token contains characters that must not appear in the HTTP Authorization header.");
 
 			request.Headers[HttpRequestHeader.Authorization] = string.Format(
@@ -108,7 +108,7 @@ namespace DotNetOpenAuth.OAuth2 {
 		/// <param name="clientIdentifier">The client identifier.</param>
 		/// <returns>The client information.  Never null.</returns>
 		internal static IConsumerDescription GetClientOrThrow(this IAuthorizationServer authorizationServer, string clientIdentifier) {
-			Contract.Requires<ArgumentException>(!String.IsNullOrEmpty(clientIdentifier));
+			Requires.NotNullOrEmpty(clientIdentifier, "clientIdentifier");
 			Contract.Ensures(Contract.Result<IConsumerDescription>() != null);
 
 			try {
diff --git a/src/DotNetOpenAuth.OAuth2/OAuth2/StandardAccessTokenAnalyzer.cs b/src/DotNetOpenAuth.OAuth2/OAuth2/StandardAccessTokenAnalyzer.cs
index 1f59e52..f2b7d1c 100644
--- a/src/DotNetOpenAuth.OAuth2/OAuth2/StandardAccessTokenAnalyzer.cs
+++ b/src/DotNetOpenAuth.OAuth2/OAuth2/StandardAccessTokenAnalyzer.cs
@@ -22,9 +22,9 @@ namespace DotNetOpenAuth.OAuth2 {
 		/// <param name="authorizationServerPublicSigningKey">The crypto service provider with the authorization server public signing key.</param>
 		/// <param name="resourceServerPrivateEncryptionKey">The crypto service provider with the resource server private encryption key.</param>
 		public StandardAccessTokenAnalyzer(RSACryptoServiceProvider authorizationServerPublicSigningKey, RSACryptoServiceProvider resourceServerPrivateEncryptionKey) {
-			Contract.Requires<ArgumentNullException>(authorizationServerPublicSigningKey != null);
-			Contract.Requires<ArgumentNullException>(resourceServerPrivateEncryptionKey != null);
-			Contract.Requires<ArgumentException>(!resourceServerPrivateEncryptionKey.PublicOnly);
+			Requires.NotNull(authorizationServerPublicSigningKey, "authorizationServerPublicSigningKey");
+			Requires.NotNull(resourceServerPrivateEncryptionKey, "resourceServerPrivateEncryptionKey");
+			Requires.True(!resourceServerPrivateEncryptionKey.PublicOnly, "resourceServerPrivateEncryptionKey");
 			this.AuthorizationServerPublicSigningKey = authorizationServerPublicSigningKey;
 			this.ResourceServerPrivateEncryptionKey = resourceServerPrivateEncryptionKey;
 		}