A **Manager** is used to manage all incoming and outgoing connections to a server.

On startup all remote servers must be specified.
From that individual connections will be spawned to each remote server,
or incoming requests will be hooked up to the appropriate connection.

To get a connection to a specific server, use `Manager.Connection(host)` to get a connection to the specified host.
From this connection individual requests can be made.

  // Node/edge sets are the same, but node/edge connections differ due to edge type.
  @Test
  public void equivalent_directedVsUndirected() {
    network.addEdge(N1, N2, E12);

    MutableNetwork<Integer, String> g2 = createNetwork(oppositeType(edgeType));
    g2.addEdge(N1, N2, E12);

    assertThat(network).isNotEqualTo(g2);
  }

  // Node/edge sets and node/edge connections are the same, but directedness differs.
  @Test

  // Node/edge sets are the same, but node/edge connections differ due to edge type.
  @Test
  public void equivalent_directedVsUndirected() {
    network.addEdge(N1, N2, E12);

    MutableNetwork<Integer, String> g2 = createNetwork(oppositeType(edgeType));
    g2.addEdge(N1, N2, E12);

    assertThat(network).isNotEqualTo(g2);
  }

  // Node/edge sets and node/edge connections are the same, but directedness differs.
  @Test

import okhttp3.internal.toImmutableList

/**
 * A specification for a connection to an origin server. For simple connections, this is the
 * server's hostname and port. If an explicit proxy is requested (or [no proxy][Proxy.NO_PROXY] is
 * explicitly requested), this also includes that proxy information. For secure connections the
 * address also includes the SSL socket factory, hostname verifier, and certificate pinner.
 *

	if err != nil {
		return err
	}

	// Wait for opened connection to be closed up to Shutdown timeout.
	return nil
}

// UseIdleTimeout configure idle connection timeout
func (srv *Server) UseIdleTimeout(d time.Duration) *Server {
	srv.IdleTimeout = d
	return srv
}

// UseReadTimeout configure connection request read timeout.
func (srv *Server) UseReadTimeout(d time.Duration) *Server {

  }

  final NetworkConnections<N, E> checkedConnections(N node) {
    NetworkConnections<N, E> connections = nodeConnections.get(node);
    if (connections == null) {
      checkNotNull(node);
      throw new IllegalArgumentException(String.format(NODE_NOT_IN_GRAPH, node));
    }
    return connections;
  }

  final N checkedReferenceNode(E edge) {
    N referenceNode = edgeToReferenceNode.get(edge);

  }

  final NetworkConnections<N, E> checkedConnections(N node) {
    NetworkConnections<N, E> connections = nodeConnections.get(node);
    if (connections == null) {
      checkNotNull(node);
      throw new IllegalArgumentException(String.format(NODE_NOT_IN_GRAPH, node));
    }
    return connections;
  }

  final N checkedReferenceNode(E edge) {
    N referenceNode = edgeToReferenceNode.get(edge);

  override fun createRequestBody(
    request: Request,
    contentLength: Long,
  ): Sink =
    when {
      request.body?.isDuplex() == true -> throw ProtocolException(
        "Duplex connections are not supported for HTTP/1",
      )
      request.isChunked -> newChunkedSink() // Stream a request body of unknown length.
      contentLength != -1L -> newKnownLengthSink() // Stream a request body of a known length.

## Retrying Requests

Sometimes connections fail: either a pooled connection was stale and disconnected, or the webserver itself couldn’t be reached. OkHttp will retry the request with a different route if one is available.

## [Calls](https://square.github.io/okhttp/4.x/okhttp/okhttp3/-call/)

// Returns:
// - A pointer to a PreparedStmtDB instance, which manages prepared statements using the provided connection pool and configuration.
func NewPreparedStmtDB(connPool ConnPool, maxSize int, ttl time.Duration) *PreparedStmtDB {
	return &PreparedStmtDB{
		ConnPool: connPool,                     // Assigns the provided connection pool to manage database connections.