public CompatibilityCassandraDatabaseSetup(bool reset = false, bool toLower = false, bool toLower2 = false)
{
this.toLower = toLower;
this.toLower2 = toLower2;
ConnectionBuilder = new ConnectionBuilder(keyspace: Keyspace, server: Server, cqlVersion: CqlVersion.Cql3);
DB = new CassandraContext(ConnectionBuilder);
if (DB.KeyspaceExists(Keyspace))
DB.DropKeyspace(Keyspace);
var keyspace = new CassandraKeyspace(new CassandraKeyspaceSchema
{
Name = Keyspace,
}, DB);
var exists = DB.KeyspaceExists(Keyspace);
if(!exists)
keyspace.TryCreateSelf();
Family = DB.GetColumnFamily<AsciiType>("Standard");
SuperFamily = DB.GetColumnFamily<AsciiType, AsciiType>("Super");
UserFamily = DB.GetColumnFamily(toLowerIf(toLower,"Users"));
if (exists && !reset)
return;
ResetDatabase();
}
private static IConnectionProvider CreateProvider(ConnectionBuilder builder)
{
if (builder.Pooled)
return new PooledConnectionProvider(builder);
else
return new NormalConnectionProvider(builder);
}
public RemoteTunnel(ConnectionBuilder cbuilder, ProtocolBuilder pfactory, int maxConnections = 2, int throttle = 0)
: this(maxConnections)
{
CreateConnection = cbuilder;
CreateProtocol = pfactory;
Throttle = throttle;
}
/// <summary>
///
/// </summary>
/// <param name="builder"></param>
public PooledConnectionProvider(ConnectionBuilder builder)
: base(builder)
{
PoolSize = builder.PoolSize;
Lifetime = builder.Lifetime;
_maintenanceTimer = new Timer(o => Cleanup(), null, 30000L, 30000L);
}
public void Configure(ConnectionBuilder builder)
{
Fiber fiber = GetConfiguredFiber(builder);
var proxy = new WcfChannelProxy(fiber, _endpointUri, _pipeName);
builder.AddChannel(proxy);
builder.AddDisposable(proxy);
}
public async Task ClientConnectionLastWillCanSendOut()
{
using (StartVerifiableLog(out var loggerFactory, LogLevel.Warning, expectedErrors: c => true,
logChecker: logs =>
{
Assert.Single(logs);
Assert.Equal("ApplicationTaskFailed", logs[0].Write.EventId.Name);
return(true);
}))
{
var ccm = new TestClientConnectionManager();
var ccf = new ClientConnectionFactory();
var protocol = new ServiceProtocol();
TestConnection transportConnection = null;
var connectionFactory = new TestConnectionFactory(conn =>
{
transportConnection = conn;
return(Task.CompletedTask);
});
var services = new ServiceCollection();
var connectionHandler = new EndlessConnectionHandler();
services.AddSingleton(connectionHandler);
var builder = new ConnectionBuilder(services.BuildServiceProvider());
builder.UseConnectionHandler <EndlessConnectionHandler>();
ConnectionDelegate handler = builder.Build();
var connection = new ServiceConnection(protocol, ccm, connectionFactory, loggerFactory, handler, ccf,
"serverId", Guid.NewGuid().ToString("N"), null, null, null, closeTimeOutMilliseconds: 500);
var connectionTask = connection.StartAsync();
// completed handshake
await connection.ConnectionInitializedTask.OrTimeout();
Assert.Equal(ServiceConnectionStatus.Connected, connection.Status);
var clientConnectionId = Guid.NewGuid().ToString();
await transportConnection.Application.Output.WriteAsync(
protocol.GetMessageBytes(new OpenConnectionMessage(clientConnectionId, new Claim[] { })));
var clientConnection = await ccm.WaitForClientConnectionAsync(clientConnectionId).OrTimeout();
clientConnection.CancelApplication();
// complete reading to end the connection
transportConnection.Application.Output.Complete();
await clientConnection.LifetimeTask.OrTimeout();
// 1s for application task to timeout
await connectionTask.OrTimeout(1000);
Assert.Equal(ServiceConnectionStatus.Disconnected, connection.Status);
Assert.Empty(ccm.ClientConnections);
connectionHandler.CancellationToken.Cancel();
}
}
private IDbConnection BuildConnection()
{
string connectionString = MySqlServer.Instance.GetConnectionString().Replace("Protocol=pipe;", "");
ConnectionBuilder connectionBuilder = new ConnectionBuilder(MySqlClientFactory.Instance);
IDbConnection connection = connectionBuilder.BuildConnection(connectionString);
connection.Open();
return(connection);
}
public void Configure(ConnectionBuilder builder, T instance)
{
Channel <TChannel> channel = _accessor(instance);
if (channel != null)
{
builder.AddChannel(channel);
}
}
public void SqlOrder_WithOrder_SetsOrderOnFieldType()
{
void Order(OrderByBuilder order, IReadOnlyDictionary <string, object> arguments,
IResolveFieldContext context, SqlTable sqlTable) => order.By("id");
var builder = ConnectionBuilder.Create <ObjectGraphType, object>().SqlOrder(Order);
builder.FieldType.GetSqlOrder().Should().Be((OrderByDelegate)Order);
}
/// <summary>
/// 静态配置
/// </summary>
public static IApplicationBuilder UseConfigRegist(this IApplicationBuilder app, IConfiguration Configuration)
{
var reg = Configuration.Get <AppConfig>();
//注册数据库
ConnectionBuilder.ConfigRegist(reg.dBSetting.ConnectionString, reg.dBSetting.DBType);
return(app);
}
private void cetak_2()
{
try
{
string text = System.IO.File.ReadAllText("./settings2.txt");
var thePrinterConn = ConnectionBuilder.Build(text);
try
{
// Open the connection - physical connection is established here.
thePrinterConn.Open();
// This example prints "This is a ZPL test." near the top of the label.
string zplData = "^XA" +
//item id
"^FO015,21^A0,34,24^FD" + txt2AsalBarang.Text + "^FS" +
"^FO440,21^A0,34,24^FD" + txt2AsalBarang.Text + "^FS" +
//item name 1
"^FO015,55^A0,34,24^FD" + txt2NamaBarang.Text + "^FS" +
"^FO440,55^A0,34,24^FD" + txt2NamaBarang.Text + "^FS" +
//item name 2
"^FO015,89^A0,34,24^FD" + txt2TipeMobil.Text + "^FS" +
"^FO440,89^A0,34,24^FD" + txt2TipeMobil.Text + "^FS" +
//item name 3
"^FO015,123^A0,34,24^FD" + txt2KodeJual.Text + "^FS" +
"^FO440,123^A0,34,24^FD" + txt2KodeJual.Text + "^FS" +
//item chinese
"^FO015,156^CI28^A@N,36,30,E:SIMSUN.FNT^FD" + txt2HurufMandarin.Text + "^FS" +
"^FO440,156^CI28^A@N,36,30,E:SIMSUN.FNT^FD" + txt2HurufMandarin.Text + "^FS" +
"^XZ";
// Send the data to printer as a byte array.
thePrinterConn.Write(Encoding.UTF8.GetBytes(zplData));
}
catch (ConnectionException ex)
{
// Handle communications error here.
Console.WriteLine(ex.ToString());
}
finally
{
// Close the connection to release resources.
thePrinterConn.Close();
}
}
catch (Exception ex)
{
MessageBox.Show(ex.ToString(), "Peringatan", MessageBoxButtons.OK, MessageBoxIcon.Warning);
}
txt2NamaBarang.Text = "";
txt2TipeMobil.Text = "";
txt2KodeJual.Text = "";
txt2KodeMandarin.Text = "";
txt2HurufMandarin.Text = "";
num2Cetak.Value = 0;
txt2NamaBarang.Focus();
}
public void Configure(ConnectionBuilder builder)
{
Fiber fiber = this.GetFiberUsingConfiguredFactory(builder);
foreach (var result in _results)
{
result.Connect(builder, fiber, _instance);
}
}
public void SqlJoin_WhenJoinIsNull_ThrowsException()
{
Action action = () => ConnectionBuilder.Create <ObjectGraphType, object>().SqlJoin(null);
action.Should()
.Throw <ArgumentNullException>()
.Which.ParamName.Should()
.Be("join");
}
public ConnectionBuilder <TParentType, TGraphType, object> Connection <TParentType, TGraphType>()
where TParentType : GraphType
where TGraphType : ObjectGraphType, new()
{
var builder = ConnectionBuilder.Create <TParentType, TGraphType>();
_fields.Add(builder.FieldType);
return(builder);
}
/// <inheritdoc cref="ConnectionBuilder{TSourceType}.Create{TNodeType, TEdgeType}(string)"/>
public ConnectionBuilder <TSourceType> Connection <TNodeType, TEdgeType>()
where TNodeType : IGraphType
where TEdgeType : EdgeType <TNodeType>
{
var builder = ConnectionBuilder.Create <TNodeType, TEdgeType, TSourceType>();
AddField(builder.FieldType);
return(builder);
}
public async Task TestServiceConnectionWithNormalApplicationTask()
{
using (StartVerifiableLog(out var loggerFactory, LogLevel.Debug))
{
var ccm = new TestClientConnectionManager();
var ccf = new ClientConnectionFactory();
var protocol = new ServiceProtocol();
TestConnection transportConnection = null;
var connectionFactory = new TestConnectionFactory(conn =>
{
transportConnection = conn;
return(Task.CompletedTask);
});
var services = new ServiceCollection();
var builder = new ConnectionBuilder(services.BuildServiceProvider());
builder.UseConnectionHandler <TestConnectionHandler>();
ConnectionDelegate handler = builder.Build();
var connection = new ServiceConnection(protocol, ccm, connectionFactory, loggerFactory, handler, ccf,
"serverId", Guid.NewGuid().ToString("N"), null, null);
var connectionTask = connection.StartAsync();
// completed handshake
await connection.ConnectionInitializedTask.OrTimeout();
Assert.Equal(ServiceConnectionStatus.Connected, connection.Status);
var clientConnectionId = Guid.NewGuid().ToString();
await transportConnection.Application.Output.WriteAsync(
protocol.GetMessageBytes(new OpenConnectionMessage(clientConnectionId, new Claim[] { })));
var clientConnection = await ccm.WaitForClientConnectionAsync(clientConnectionId).OrTimeout();
await transportConnection.Application.Output.WriteAsync(
protocol.GetMessageBytes(new CloseConnectionMessage(clientConnectionId)));
// Normal end with close message
await ccm.WaitForClientConnectionRemovalAsync(clientConnectionId).OrTimeout();
// another connection comes in
clientConnectionId = Guid.NewGuid().ToString();
await transportConnection.Application.Output.WriteAsync(
protocol.GetMessageBytes(new OpenConnectionMessage(clientConnectionId, new Claim[] { })));
clientConnection = await ccm.WaitForClientConnectionAsync(clientConnectionId).OrTimeout();
// complete reading to end the connection
transportConnection.Application.Output.Complete();
await connectionTask.OrTimeout();
Assert.Equal(ServiceConnectionStatus.Disconnected, connection.Status);
Assert.Empty(ccm.ClientConnections);
}
}
public void AddNavigationConnectionField <TSource, TReturn>(
ComplexGraphType <TSource> graph,
string name,
Func <ResolveEfFieldContext <TDbContext, TSource>, IEnumerable <TReturn> >?resolve = null,
Type?itemGraphType = null,
IEnumerable <QueryArgument>?arguments = null,
IEnumerable <string>?includeNames = null,
int pageSize = 10,
string?description = null)
where TReturn : class
{
Guard.AgainstNull(nameof(graph), graph);
Guard.AgainstNullWhiteSpace(nameof(name), name);
Guard.AgainstNegative(nameof(pageSize), pageSize);
itemGraphType ??= GraphTypeFinder.FindGraphType <TReturn>();
var fieldType = GetFieldType <TSource>(name, itemGraphType);
var builder = ConnectionBuilder <TSource> .Create <FakeGraph>(name);
if (description != null)
{
builder.Description(description);
}
builder.PageSize(pageSize).Bidirectional();
SetField(builder, fieldType);
IncludeAppender.SetIncludeMetadata(builder.FieldType, name, includeNames);
if (resolve != null)
{
builder.ResolveAsync(async context =>
{
var efFieldContext = BuildContext(context);
var enumerable = resolve(efFieldContext);
enumerable = enumerable.ApplyGraphQlArguments(context);
enumerable = await efFieldContext.Filters.ApplyFilter(enumerable, context.UserContext);
var page = enumerable.ToList();
return(ConnectionConverter.ApplyConnectionContext(
page,
context.First,
context.After,
context.Last,
context.Before));
});
}
var connection = builder;
var field = graph.AddField(connection.FieldType);
field.AddWhereArgument(arguments);
}
static void Main(string[] args)
{
var connection = new ConnectionBuilder()
.WithLogging()
.Build();
// <string, string> = <T, T> = <InputDataType, OutputDataType>
connection.On <string, string>("greeting", x => x + " World ! (from Core)");
connection.Listen();
}
public void TestMultipleServersWithHostAndMixedPorts()
{
var servers = new ConnectionBuilder("Server=host:123,host2,host3:789;Connection Timeout=5").Servers;
Assert.Equal(3, servers.Count);
foreach (var server in servers)
{
Assert.Equal(5, server.Timeout);
}
}
/// <summary>
///
/// </summary>
/// <param name="builder"></param>
public NormalConnectionProvider(ConnectionBuilder builder)
: base(builder)
{
if (builder.Servers.Count > 1 && builder.Timeout == 0)
throw new ElasticSearchException("You must specify a timeout when using multiple servers.");
Timeout = builder.Timeout;
ActiveServers = builder.Servers;
TSocketSetting = builder.TSocketSetting;
}
private void Start <THub>() where THub : Hub
{
var app = new ConnectionBuilder(_serviceProvider)
.UseHub <THub>()
.Build();
var dispatcher = _serviceProvider.GetRequiredService <ServiceHubDispatcher <THub> >();
dispatcher.Start(app);
}
/// <summary>
/// Maps incoming requests with the specified path to the provided connection pipeline.
/// </summary>
/// <param name="path">The request path.</param>
/// <param name="options">Options used to configure the connection.</param>
/// <param name="configure">A callback to configure the connection.</param>
public void MapConnections(PathString path, HttpConnectionDispatcherOptions options, Action <IConnectionBuilder> configure)
{
var connectionBuilder = new ConnectionBuilder(_routes.ServiceProvider);
configure(connectionBuilder);
var socket = connectionBuilder.Build();
_routes.MapRoute(path, c => _dispatcher.ExecuteAsync(c, options, socket));
_routes.MapRoute(path + "/negotiate", c => _dispatcher.ExecuteNegotiateAsync(c, options));
}
static void Main(string[] args)
{
var connection = new ConnectionBuilder()
.WithLogging()
.Build();
connection.On <string, string>("greeting", name => "Hello " + name);
connection.Listen();
}
static void Main(string[] args)
{
var connection = new ConnectionBuilder()
.WithLogging()
.Build();
connection.On <string, string>("greeting", (val) => $"Hello {val}");
connection.Listen();
}
public static void ConfigureServices(string remoteHost, int remotePort, int localPort)
{
ConnectionBuilder connBuilder = new ConnectionBuilder();
ConnServ = connBuilder.
ConfigureLocal(localPort)
.ConfigureRemote(remoteHost, remotePort)
.Build();
MessageStorage = new FileStorage($@"{remoteHost}{remotePort}.txt");
MessageServ = new MessageService.MessageService(MessageStorage);
}
private Task<IConnection> CreateConnection(CancellationToken cancellationToken)
{
var ctx = new Context();
ctx.SetRetryCount(0);
return _connectionRetryPolicy.ExecuteAsync((context, ct) =>
{
var endpoint = GetCurrentEndpoint(context);
var connectionBuilder = new ConnectionBuilder(_loggerFactory, _messageIdPolicyFactory);
return connectionBuilder.CreateAsync(endpoint, ct);
}, ctx, cancellationToken);
}
private ConnectionBuilder Initialize()
{
var connections = new ConnectionBuilder()
{
options_ = Options
};
OnConfiguring(connections);
OnModelCreating(connections);
return(connections);
}
public static void ResolveApiConnection <TEntity>(
this ConnectionBuilder <object> builder,
Swapi api
) where TEntity : Entity
{
builder
.ResolveAsync(async ctx => await api
.GetConnectionAsync <TEntity>(ctx.GetConnectionArguments())
.ContinueWith(t => ctx.ToConnection(t.Result.Entities, t.Result.TotalCount))
);
}
public static Fiber GetFiberUsingConfiguredFactory <T, TChannel>(this FiberFactoryConfiguratorImpl <T> configurator,
ConnectionBuilder <TChannel> builder)
where T : class
{
FiberFactory fiberFactory = configurator.GetConfiguredFiberFactory();
Fiber fiber = fiberFactory();
builder.AddDisposable(fiber.ShutdownOnDispose(configurator.ShutdownTimeout));
return(fiber);
}
static void Main(string[] args)
{
Assembly myassembly = Assembly.LoadFrom("HelloWorld.dll");
var connection = new ConnectionBuilder()
.WithLogging()
.Build();
connection.On <string, string>("greeting", name => "The c# part sais hello: " + name);
connection.Listen();
}
/// <summary>
/// Sets whether the result set should be paginated.
/// </summary>
/// <param name="builder">The connection builder.</param>
/// <param name="paginate">Should the result be paginated?</param>
/// <returns>The <see cref="ConnectionBuilder{T}"/>.</returns>
/// <exception cref="ArgumentNullException">If <paramref name="builder"/> is <c>null</c>.</exception>
public static ConnectionBuilder <T> SqlPaginate <T>(this ConnectionBuilder <T> builder, bool paginate = true)
{
if (builder == null)
{
throw new ArgumentNullException(nameof(builder));
}
builder.FieldType.SqlPaginate(paginate);
return(builder);
}
private static IConnectionProvider CreateProvider(ConnectionBuilder builder)
{
if (builder.Pooled)
{
return(new PooledConnectionProvider(builder));
}
else
{
return(new NormalConnectionProvider(builder));
}
}
public void SqlJoin_WithJoin_SetsJoinOnFieldType()
{
void Join(JoinBuilder join, IReadOnlyDictionary <string, object> arguments,
IResolveFieldContext context, Node sqlAstNode)
{
}
var builder = ConnectionBuilder.Create <ObjectGraphType, object>().SqlJoin(Join);
builder.FieldType.GetSqlJoin().Should().Be((JoinDelegate)Join);
}
public void SqlWhere_WithQuery_SetsQueryOnFieldType()
{
void Where(WhereBuilder where, IReadOnlyDictionary <string, object> arguments,
IResolveFieldContext context, SqlTable sqlAStNode)
{
}
var builder = ConnectionBuilder.Create <ObjectGraphType, object>().SqlWhere(Where);
builder.FieldType.GetSqlWhere().Should().Be((WhereDelegate)Where);
}
private void print_label()
{
String itemId = txtItemId.Text;
String itemName1 = txtItemName1.Text;
String itemName2 = txtItemName2.Text;
String itemName3 = txtItemName3.Text;
String itemChinese = txtItemChinese.Text;
//Connection thePrinterConn = new TcpConnection("127.0.0.1", TcpConnection.DEFAULT_ZPL_TCP_PORT);
///Connection thePrinterConn = new UsbConnection("Port_#0001.Hub_#0004");
var thePrinterConn = ConnectionBuilder.Build("USB:ZDesigner GT800 (ZPL)");
try
{
// Open the connection - physical connection is established here.
thePrinterConn.Open();
// This example prints "This is a ZPL test." near the top of the label.
string zplData = "^XA" +
//item id
"^FO00,22^A0,38,26^FD" + itemId + "^FS" +
"^FO290,22^A0,38,26^FD" + itemId + "^FS" +
"^FO580,22^A0,38,26^FD" + itemId + "^FS" +
//item name 1
"^FO00,55^A0,30,22^FD" + itemName1 + "^FS" +
"^FO290,55^A0,30,22^FD" + itemName1 + "^FS" +
"^FO580,55^A0,30,22^FD" + itemName1 + "^FS" +
//item name 2
"^FO00,82^A0,30,22^FD" + itemName2 + "^FS" +
"^FO290,82^A0,30,22^FD" + itemName2 + "^FS" +
"^FO580,82^A0,30,22^FD" + itemName2 + "^FS" +
//item name 3
"^FO00,108^A0,30,22^FD" + itemName3 + "^FS" +
"^FO290,108^A0,30,22^FD" + itemName3 + "^FS" +
"^FO580,108^A0,30,22^FD" + itemName3 + "^FS" +
//item chinese
"^FO00,138^CI28^A@N,40,40,E:SIMSUN.FNT^FD" + itemChinese + "^FS" +
"^FO290,138^CI28^A@N,40,40,E:SIMSUN.FNT^FD" + itemChinese + "^FS" +
"^FO580,138^CI28^A@N,40,40,E:SIMSUN.FNT^FD" + itemChinese + "^FS" +
"^XZ";
// Send the data to printer as a byte array.
thePrinterConn.Write(Encoding.UTF8.GetBytes(zplData));
}
catch (ConnectionException e)
{
// Handle communications error here.
Console.WriteLine(e.ToString());
}
finally
{
// Close the connection to release resources.
thePrinterConn.Close();
}
}
public void DeleteProfile(ConnectionBuilder connection)
{
string statment = string.Format("delete from users where login = '******';", Login);
try
{
connection.ExecuteDeleteSQL(statment);
}
catch(Exception e)
{
throw e;
}
}
public void PooledConnectionProvider()
{
// arrange
var expected = typeof(PooledConnectionProvider);
var connectionString = "Keyspace=Testing;Pooled=True";
// act
var result = new ConnectionBuilder(connectionString);
var actual = ConnectionProviderFactory.Get(result).GetType();
// assert
Assert.AreEqual(expected, actual);
}
public static IConnectionProvider Get(ConnectionBuilder connectionBuilder)
{
IConnectionProvider provider;
if (!_providers.TryGetValue(connectionBuilder.ConnectionString, out provider))
using (TimedLock.Lock(_lock))
{
provider = CreateProvider(connectionBuilder);
_providers.Add(connectionBuilder.ConnectionString, provider);
}
return provider;
}
public RemoteTunnel(string url, DataEncoding encoding = DataEncoding.Proto, int maxConnections = 2) : this(maxConnections)
{
if (url == null)
throw new ArgumentNullException();
EndPoint = new Uri(url);
var throttle = 0;
CreateConnection = ConnectionBuilderFromUri(EndPoint, out throttle);
Throttle = throttle;
switch (encoding)
{
case DataEncoding.Memcached:
CreateProtocol = (dtc) => { return new Memcached.ClientProtocol(dtc); }; break;
default:
throw new NotImplementedException(encoding.ToString());
}
}
public CassandraDatabaseSetup(bool reset = false)
{
ConnectionBuilder = new ConnectionBuilder(keyspace: Keyspace, server: Server);
DB = new CassandraContext(ConnectionBuilder);
var exists = DB.KeyspaceExists(Keyspace);
Family = DB.GetColumnFamily<AsciiType>("Standard");
SuperFamily = DB.GetColumnFamily<AsciiType, AsciiType>("Super");
UserFamily = DB.GetColumnFamily("Users");
if (exists && !reset)
return;
ResetDatabase();
}
public void Fails_Over()
{
// arrange
var expectedHost = "127.0.0.1";
var expectedPort = Server.DefaultPort;
// act
var result = new ConnectionBuilder(FailoverConnectionString);
var provider = ConnectionProviderFactory.Get(result);
var conn = provider.Open();
var actualHost = conn.Server.Host;
var actualPort = conn.Server.Port;
// assert
Assert.AreEqual(expectedHost, actualHost);
Assert.AreEqual(expectedPort, actualPort);
}
public GenericDatabaseSetup(bool reset = false)
{
ConnectionBuilder = new ConnectionBuilder(keyspace: Keyspace, server: Server, cqlVersion: CqlVersion.Cql3);
DB = new CassandraContext(ConnectionBuilder);
if (DB.KeyspaceExists(Keyspace))
DB.DropKeyspace(Keyspace);
var keyspace = new CassandraKeyspace(new CassandraKeyspaceSchema
{
Name = Keyspace,
}, DB);
var exists = DB.KeyspaceExists(Keyspace);
if (!exists)
keyspace.TryCreateSelf();
if (exists && !reset)
return;
ResetDatabase();
}
public LoginDelegate(ConnectionBuilder connectionBuilder)
{
_conn = connectionBuilder;
}
public CassandraSession(ConnectionBuilder connectionBuilder)
: this(ConnectionProviderFactory.Get(connectionBuilder), connectionBuilder.ReadConsistency, connectionBuilder.WriteConsistency)
{
}
public void Configure(ConnectionBuilder builder)
{
builder.AddChannel(_channel);
}
/// <summary>
///
/// </summary>
/// <param name="builder"></param>
protected ConnectionProvider(ConnectionBuilder builder)
{
Builder = builder;
}
public Connection(ConnectionBuilder builder)
{
this.from = builder.A;
this.to = builder.B;
this.distance = builder.Distance;
}