import java.util.NoSuchElementException;
import java.util.Set;
import javax.annotation.CheckForNull;

/**
 * A set comprising zero or more {@linkplain Range#isEmpty nonempty}, {@linkplain
 * Range#isConnected(Range) disconnected} ranges of type {@code C}.
 *
 * <p>Implementations that choose to support the {@link #add(Range)} operation are required to
 * ignore empty ranges and coalesce connected ranges. For example:
 *
 * <pre>{@code

    protected void finalize () throws Throwable {
        if ( isConnected() && this.usageCount.get() != 0 ) {
            log.warn("Tree was not properly released");
        }
    }


    /**
     * 
     * @return whether the tree is connected
     */
    public boolean isConnected () {
        return this.tid != -1 && this.session.isConnected() && this.connectionState.get() == 2;
    }


    /**

	"net"
	"syscall"
	"time"
)

// CheckPortAvailability - check if given host and port is already in use.
// Note: The check method tries to listen on given port and closes it.
// It is possible to have a disconnected client in this tiny window of time.
func CheckPortAvailability(host, port string, opts TCPOptions) (err error) {
	lc := &net.ListenConfig{
		Control: func(network, address string, c syscall.RawConn) error {

import (
	"context"
	"net"
	"time"
)

// CheckPortAvailability - check if given host and port is already in use.
// Note: The check method tries to listen on given port and closes it.
// It is possible to have a disconnected client in this tiny window of time.
func CheckPortAvailability(host, port string, opts TCPOptions) (err error) {
	lc := &net.ListenConfig{}

	ctx, cancel := context.WithTimeout(context.Background(), time.Second)

	"sync"
	"time"

	"github.com/gobwas/ws"
	"github.com/gobwas/ws/wsutil"
)

// ErrDisconnected is returned when the connection to the remote has been lost during the call.
var ErrDisconnected = RemoteErr("remote disconnected")

const (
	// minBufferSize is the minimum buffer size.
	// Buffers below this is not reused.
	minBufferSize = 1 << 10

	// defaultBufferSize is the default buffer allocation size.
	defaultBufferSize = 4 << 10

			return
		}
		if debugPrint {
			fmt.Println(c.Local, "Disconnected. Attempting to reconnect.")
		}
	}
}

func (c *Connection) disconnected() {
	c.outgoing.Range(func(key uint64, client *muxClient) bool {
		if !client.stateless {
			client.cancelFn(ErrDisconnected)
		}
		return true
	})
	if debugReqs {
		fmt.Println(c.String(), "Disconnected. Clearing outgoing.")
	}
	c.outgoing.Clear()

			result.Concurrent = concurrency

			select {
			case ch <- result:
			case <-ctx.Done():
				return
			}
		}

		for {
			select {
			case <-ctx.Done():
				// If the client got disconnected stop the speedtest.
				return
			default:
			}

			sopts := speedTestOpts{
				objectSize:      opts.objectSize,
				concurrency:     concurrency,
				duration:        opts.duration,

   *
   * <p>The intersection exists if and only if the two ranges are {@linkplain #isConnected
   * connected}.
   *
   * <p>The intersection operation is commutative, associative and idempotent, and its identity
   * element is {@link Range#all}).
   *
   * @throws IllegalArgumentException if {@code isConnected(connectedRange)} is {@code false}
   */
  public Range<C> intersection(Range<C> connectedRange) {

					return
				}
				if c.HealthCheckFn() {
					if atomic.CompareAndSwapInt32(&c.connected, offline, online) {
						now := time.Now()
						disconnected := now.Sub(c.LastConn())
						logger.Event(context.Background(), "healthcheck", "Client '%s' re-connected in %s", c.url.String(), disconnected)
						atomic.StoreInt64(&c.lastConn, now.UnixNano())
					}
					return
				}
				attempt++
				time.Sleep(backOff(attempt))
			}

// the last peer to connect and the first peer to disconnect.
// This is to improve the RX throughput accuracy.
type netPerfRX struct {
	RX                uint64    // RX bytes
	lastToConnect     time.Time // time at which last peer to connect to us
	firstToDisconnect time.Time // time at which the first peer disconnects from us
	RXSample          uint64    // RX bytes between lastToConnect and firstToDisconnect