# Class AbstractEndpoint<S,U>

java.lang.Object
org.apache.tomcat.util.net.AbstractEndpoint<S,U>

Type Parameters:
  `S` - The type used by the socket wrapper associated with this endpoint. Might be the same as U.
  `U` - The type of the underlying socket used by this endpoint. Might be the same as S.

Direct Known Subclasses:
  `AbstractJsseEndpoint, AprEndpoint`

public abstract class AbstractEndpoint<S,U> extends Object
Abstract endpoint implementation.

- ## Nested Class Summary

  Nested Classes
  Modifier and Type
  Class
  Description
  `protected static enum`
  `AbstractEndpoint.BindState`
  Enum representing the possible states of the bind operation.
  `static interface`
  `AbstractEndpoint.Handler<S>`
  Interface for handlers used by an endpoint.

- ## Field Summary

  Fields
  Modifier and Type
  Field
  Description
  `protected Acceptor<U>`
  `acceptor`
  Thread used to accept new connections and pass them to worker threads.
  `protected int`
  `acceptorThreadCount`
  Deprecated.
  This attribute is hard-coded to `1` and is no longer configurable.
  `protected int`
  `acceptorThreadPriority`
  Priority of the acceptor threads.
  `protected HashMap<String,Object>`
  `attributes`
  Attributes provide a way for configuration to be passed to subcomponents without the `ProtocolHandler` being aware of the properties available on those subcomponents.
  `protected Map<U, SocketWrapperBase<S>>`
  `connections`
  Map holding all current connections keyed with the sockets.
  `protected boolean`
  `internalExecutor`
  Are we using an internal executor
  `protected final List<String>`
  `negotiableProtocols`
  List of protocols that can be negotiated (e.g.
  `protected boolean`
  `paused`
  Will be set to true whenever the endpoint is paused.
  `protected SynchronizedStack<SocketProcessorBase<S>>`
  `processorCache`
  Cache for SocketProcessor objects
  `protected boolean`
  `running`
  Running state of the endpoint.
  `protected static final StringManager`
  `sm`
  String manager for this package.
  `protected final SocketProperties`
  `socketProperties`
  Socket properties
  `protected ConcurrentMap<String, SSLHostConfig>`
  `sslHostConfigs`
  Map of SSL host configurations keyed by host name.
  `protected int`
  `threadPriority`
  Priority of the worker threads.

- ## Constructor Summary

  Constructors
  Constructor
  Description
  `AbstractEndpoint()`
  Construct and return an endpoint.

- ## Method Summary

  Modifier and Type
  Method
  Description
  `void`
  `addNegotiatedProtocol(String negotiableProtocol)`
  Add a protocol that can be negotiated (e.g.
  `void`
  `addSslHostConfig(SSLHostConfig sslHostConfig)`
  Add the given SSL Host configuration.
  `void`
  `addSslHostConfig(SSLHostConfig sslHostConfig, boolean replace)`
  Add the given SSL Host configuration, optionally replacing the existing configuration for the given host.
  `final long`
  `awaitConnectionsClose(long waitMillis)`
  Wait for the client connections to the server to close gracefully.
  `abstract void`
  `bind()`
  Bind the endpoint to its port and address.
  `boolean`
  `checkSni(String sniHostName, String protocolHostName)`
  Check if two host names share the same SSLHostConfig.
  `final void`
  `closeServerSocketGraceful()`
  Close the server socket (to prevent further connections) if the server socket was originally bound on `start()` (rather than on `init()`).
  `protected void`
  `closeSocket(U socket)`
  Close the socket when the connection has to be immediately closed when an error occurs while configuring the accepted socket or trying to dispatch it for processing.
  `protected long`
  `countDownConnection()`
  Count down a connection.
  `protected void`
  `countUpOrAwaitConnection()`
  Count up or await a connection slot.
  `void`
  `createExecutor()`
  Create the internal executor.
  `protected abstract SocketProcessorBase<S>`
  `createSocketProcessor(SocketWrapperBase<S> socketWrapper, SocketEvent event)`
  Create a socket processor for the given socket wrapper.
  `protected abstract void`
  `createSSLContext(SSLHostConfig sslHostConfig)`
  Create the SSLContext for the given SSLHostConfig.
  `final void`
  `destroy()`
  Destroy the endpoint and release all resources.
  `protected abstract void`
  `destroySocket(U socket)`
  Close the socket.
  `protected void`
  `destroySsl()`
  Destroy the SSL configuration.
  `protected abstract void`
  `doCloseServerSocket()`
  Actually close the server socket but don't perform any other clean-up.
  `SSLHostConfig[]`
  `findSslHostConfigs()`
  Find all SSL host configurations.
  `protected String`
  `generateCertificateDebug(X509Certificate certificate)`
  Generate debug information about a certificate.
  `int`
  `getAcceptCount()`
  Get the accept count.
  `int`
  `getAcceptorThreadCount()`
  Deprecated.
  This attribute is hard-coded to `1` and is no longer configurable.
  `int`
  `getAcceptorThreadPriority()`
  Get the acceptor thread priority.
  `InetAddress`
  `getAddress()`
  Get the bind address.
  `Object`
  `getAttribute(String key)`
  Used by subcomponents to retrieve configuration information.
  `boolean`
  `getBindOnInit()`
  Get the bind on init flag.
  `protected AbstractEndpoint.BindState`
  `getBindState()`
  Get the current bind state.
  `long`
  `getConnectionCount()`
  Return the current count of connections handled by this endpoint, if the connections are counted (which happens when the maximum count of connections is limited), or `-1` if they are not.
  `int`
  `getConnectionLinger()`
  Socket linger.
  `Set<SocketWrapperBase<S>>`
  `getConnections()`
  Get a set with the current open connections.
  `int`
  `getConnectionTimeout()`
  Socket timeout.
  `int`
  `getCurrentThreadCount()`
  Return the amount of threads that are managed by the pool.
  `int`
  `getCurrentThreadsBusy()`
  Return the amount of threads that are in use
  `boolean`
  `getDaemon()`
  Check if the threads are daemon threads.
  `String`
  `getDefaultSSLHostConfigName()`
  Get the host name for the default SSL configuration for this endpoint - always in lower case.
  `protected abstract boolean`
  `getDeferAccept()`
  `String`
  `getDomain()`
  Get the JMX domain.
  `Executor`
  `getExecutor()`
  Get the external executor.
  `long`
  `getExecutorTerminationTimeoutMillis()`
  Get the executor termination timeout.
  `AbstractEndpoint.Handler<S>`
  `getHandler()`
  Get the handler.
  `String`
  `getId()`
  The default behavior is to identify connectors uniquely with address and port.
  `int`
  `getKeepAliveTimeout()`
  Get the keepalive timeout.
  `protected abstract InetSocketAddress`
  `getLocalAddress()`
  Obtain the network address the server socket is bound to.
  `final int`
  `getLocalPort()`
  Get the local port the server socket is bound to.
  `protected abstract Log`
  `getLog()`
  Get the logger for this endpoint.
  `protected Log`
  `getLogCertificate()`
  Get the logger for certificate-related messages.
  `int`
  `getMaxConnections()`
  Get the maximum number of connections.
  `int`
  `getMaxKeepAliveRequests()`
  Get the maximum number of keep alive requests.
  `int`
  `getMaxQueueSize()`
  Get the maximum queue size.
  `int`
  `getMaxThreads()`
  Get the maximum number of worker threads.
  `int`
  `getMinSpareThreads()`
  Get the minimum number of spare threads.
  `String`
  `getName()`
  Get the name of the thread pool.
  `int`
  `getPort()`
  Get the server socket port.
  `int`
  `getPortOffset()`
  Get the port offset.
  `int`
  `getPortWithOffset()`
  Get the port with offset applied.
  `String`
  `getProperty(String name)`
  Get the value of the specified property.
  `SocketProperties`
  `getSocketProperties()`
  Get the socket properties.
  `protected SSLHostConfig`
  `getSSLHostConfig(String sniHostName)`
  Look up the SSLHostConfig for the given host name.
  `boolean`
  `getStrictSni()`
  Get the strict SNI check flag.
  `boolean`
  `getTcpNoDelay()`
  Socket TCP no delay.
  `int`
  `getThreadPriority()`
  Get the priority of the worker threads.
  `int`
  `getThreadsMaxIdleTime()`
  Get the maximum idle time for threads in the internal thread pool.
  `boolean`
  `getUseAsyncIO()`
  Check if asynchronous IO is enabled.
  `boolean`
  `getUseSendfile()`
  Get the sendfile flag.
  `boolean`
  `getUseVirtualThreads()`
  Get whether virtual threads are enabled.
  `ScheduledExecutorService`
  `getUtilityExecutor()`
  Get the utility executor.
  `boolean`
  `hasNegotiableProtocols()`
  Check if there are any negotiable protocols configured.
  `final void`
  `init()`
  Initialize the endpoint.
  `protected LimitLatch`
  `initializeConnectionLatch()`
  Initialize the connection latch if it has not already been created.
  `abstract boolean`
  `isAlpnSupported()`
  Identifies if the endpoint supports ALPN.
  `boolean`
  `isPaused()`
  Check if the endpoint is paused.
  `boolean`
  `isRunning()`
  Check if the endpoint is running.
  `boolean`
  `isSSLEnabled()`
  Check if SSL is enabled.
  `protected void`
  `logCertificate(SSLHostConfigCertificate certificate)`
  Log information about the given certificate.
  `void`
  `pause()`
  Pause the endpoint, which will stop it accepting new connections and unlock the acceptor.
  `boolean`
  `processSocket(SocketWrapperBase<S> socketWrapper, SocketEvent event, boolean dispatch)`
  Process the given SocketWrapper with the given status.
  `protected void`
  `releaseSSLContext(SSLHostConfig sslHostConfig)`
  Release the SSLContext, if any, associated with the SSLHostConfig.
  `void`
  `reloadSslHostConfig(String hostName)`
  Re-read the configuration files for the SSL host and replace the existing SSL configuration with the updated settings.
  `void`
  `reloadSslHostConfigs()`
  Re-read the configuration files for all SSL hosts and replace the existing SSL configuration with the updated settings.
  `SSLHostConfig`
  `removeSslHostConfig(String hostName)`
  Removes the SSL host configuration for the given host name, if such a configuration exists.
  `void`
  `resume()`
  Resume the endpoint, which will make it start accepting new connections again.
  `protected abstract U`
  `serverSocketAccept()`
  Accept a connection from the server socket.
  `void`
  `setAcceptCount(int acceptCount)`
  Set the accept count.
  `void`
  `setAcceptorThreadCount(int acceptorThreadCount)`
  Deprecated.
  This attribute is hard-coded to `1` and is no longer configurable.
  `void`
  `setAcceptorThreadPriority(int acceptorThreadPriority)`
  Set the acceptor thread priority.
  `void`
  `setAddress(InetAddress address)`
  Set the bind address.
  `void`
  `setAttribute(String name, Object value)`
  Generic property setter called when a property for which a specific setter already exists within the `ProtocolHandler` needs to be made available to subcomponents.
  `void`
  `setBindOnInit(boolean b)`
  Set the bind on init flag.
  `void`
  `setConnectionLinger(int connectionLinger)`
  Set the connection linger time.
  `void`
  `setConnectionTimeout(int soTimeout)`
  Set the connection timeout.
  `void`
  `setDaemon(boolean b)`
  Set whether the threads should be daemon threads.
  `protected abstract void`
  `setDefaultSslHostConfig(SSLHostConfig sslHostConfig)`
  `void`
  `setDefaultSSLHostConfigName(String defaultSSLHostConfigName)`
  Set the host name for the default SSL configuration.
  `void`
  `setDomain(String domain)`
  Set the domain for JMX registration.
  `void`
  `setExecutor(Executor executor)`
  Set the external executor.
  `void`
  `setExecutorTerminationTimeoutMillis(long executorTerminationTimeoutMillis)`
  Set the executor termination timeout.
  `void`
  `setHandler(AbstractEndpoint.Handler<S> handler)`
  Set the handler for this endpoint.
  `void`
  `setKeepAliveTimeout(int keepAliveTimeout)`
  Set the keepalive timeout.
  `void`
  `setMaxConnections(int maxCon)`
  Set the maximum number of connections.
  `void`
  `setMaxKeepAliveRequests(int maxKeepAliveRequests)`
  Set the maximum number of keep alive requests.
  `void`
  `setMaxQueueSize(int maxQueueSize)`
  Set the maximum task queue size.
  `void`
  `setMaxThreads(int maxThreads)`
  Set the maximum number of worker threads.
  `void`
  `setMinSpareThreads(int minSpareThreads)`
  Set the minimum number of spare threads.
  `void`
  `setName(String name)`
  Set the name of the thread pool.
  `void`
  `setPort(int port)`
  Set the server socket port.
  `void`
  `setPortOffset(int portOffset)`
  Set the port offset.
  `boolean`
  `setProperty(String name, String value)`
  Set the specified property.
  `protected abstract boolean`
  `setSocketOptions(U socket)`
  Set the socket options for the given accepted socket.
  `void`
  `setSSLEnabled(boolean SSLEnabled)`
  Set the SSL enabled flag.
  `void`
  `setStrictSni(boolean strictSni)`
  Set the strict SNI check flag.
  `void`
  `setTcpNoDelay(boolean tcpNoDelay)`
  Set the TCP no delay flag.
  `void`
  `setThreadPriority(int threadPriority)`
  Set the priority of the worker threads.
  `void`
  `setThreadsMaxIdleTime(int threadsMaxIdleTime)`
  Set the maximum idle time for threads in the internal thread pool.
  `void`
  `setUseAsyncIO(boolean useAsyncIO)`
  Set whether asynchronous IO is enabled.
  `void`
  `setUseSendfile(boolean useSendfile)`
  Set the sendfile flag.
  `void`
  `setUseVirtualThreads(boolean useVirtualThreads)`
  Set whether virtual threads should be used.
  `void`
  `setUtilityExecutor(ScheduledExecutorService utilityExecutor)`
  Set the utility executor.
  `void`
  `shutdownExecutor()`
  Shutdown the internal executor.
  `final void`
  `start()`
  Start the endpoint.
  `protected void`
  `startAcceptorThread()`
  Start the acceptor thread.
  `abstract void`
  `startInternal()`
  Start the endpoint internal components.
  `final void`
  `stop()`
  Stop the endpoint.
  `abstract void`
  `stopInternal()`
  Stop the endpoint internal components.
  `static long`
  `toTimeout(long timeout)`
  Convert a timeout value to a positive timeout suitable for use with socket operations.
  `abstract void`
  `unbind()`
  `protected void`
  `unlockAccept()`
  Unlock the server socket acceptor threads using bogus connections.

  ### Methods inherited from class Object

  `clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait`

- ## Field Details

  - ### sm

    protected static final StringManager sm
    String manager for this package.

  - ### running

    protected volatile boolean running
    Running state of the endpoint.

  - ### paused

    protected volatile boolean paused
    Will be set to true whenever the endpoint is paused.

  - ### internalExecutor

    protected volatile boolean internalExecutor
    Are we using an internal executor

  - ### socketProperties

    protected final SocketProperties socketProperties
    Socket properties

  - ### acceptor

    protected Acceptor<U> acceptor
    Thread used to accept new connections and pass them to worker threads.

  - ### processorCache

    protected SynchronizedStack<SocketProcessorBase<S>> processorCache
    Cache for SocketProcessor objects

  - ### connections

    protected Map<U, SocketWrapperBase<S>> connections
    Map holding all current connections keyed with the sockets.

  - ### sslHostConfigs

    protected ConcurrentMap<String, SSLHostConfig> sslHostConfigs
    Map of SSL host configurations keyed by host name.

  - ### acceptorThreadCount

    @Deprecated protected int acceptorThreadCount
    Deprecated.
    This attribute is hard-coded to `1` and is no longer configurable. It will be removed in Tomcat 10.1.
    Unused.

  - ### acceptorThreadPriority

    protected int acceptorThreadPriority
    Priority of the acceptor threads.

  - ### threadPriority

    protected int threadPriority
    Priority of the worker threads.

  - ### negotiableProtocols

    protected final List<String> negotiableProtocols
    List of protocols that can be negotiated (e.g. ALPN).

  - ### attributes

    protected HashMap<String,Object> attributes
    Attributes provide a way for configuration to be passed to subcomponents without the `ProtocolHandler` being aware of the properties available on those subcomponents.

- ## Constructor Details

  - ### AbstractEndpoint

    public AbstractEndpoint()
    Construct and return an endpoint.

- ## Method Details

  - ### toTimeout

    public static long toTimeout(long timeout)
    Convert a timeout value to a positive timeout suitable for use with socket operations.
    Parameters:
      `timeout` - The timeout value in milliseconds. If less than or equal to 0, returns `Long.MAX_VALUE`.
    Returns:
      The timeout value, or `Long.MAX_VALUE` if the input is less than or equal to 0

  - ### getSocketProperties

    public SocketProperties getSocketProperties()
    Get the socket properties.
    Returns:
      The socket properties

  - ### getConnections

    public Set<SocketWrapperBase<S>> getConnections()
    Get a set with the current open connections.
    Returns:
      A set with the open socket wrappers

  - ### getStrictSni

    public boolean getStrictSni()
    Get the strict SNI check flag.
    Returns:
      True if strict SNI checking is enabled

  - ### setStrictSni

    public void setStrictSni(boolean strictSni)
    Set the strict SNI check flag.
    Parameters:
      `strictSni` - True to enable strict SNI checking

  - ### getDefaultSSLHostConfigName

    public String getDefaultSSLHostConfigName()
    Get the host name for the default SSL configuration for this endpoint - always in lower case.
    Returns:
      The host name for the default SSL configuration for this endpoint - always in lower case.

  - ### setDefaultSSLHostConfigName

    public void setDefaultSSLHostConfigName(String defaultSSLHostConfigName)
    Set the host name for the default SSL configuration.
    Parameters:
      `defaultSSLHostConfigName` - The default SSL host configuration name

  - ### addSslHostConfig

    public void addSslHostConfig(SSLHostConfig sslHostConfig) throws IllegalArgumentException
    Add the given SSL Host configuration.
    Parameters:
      `sslHostConfig` - The configuration to add
    Throws:
      `IllegalArgumentException` - If the host name is not valid or if a configuration has already been provided for that host

  - ### addSslHostConfig

    public void addSslHostConfig(SSLHostConfig sslHostConfig, boolean replace) throws IllegalArgumentException
    Add the given SSL Host configuration, optionally replacing the existing configuration for the given host.
    Parameters:
      `sslHostConfig` - The configuration to add
      `replace` - If `true` replacement of an existing configuration is permitted, otherwise any such attempted replacement will trigger an exception
    Throws:
      `IllegalArgumentException` - If the host name is not valid or if a configuration has already been provided for that host and replacement is not allowed

  - ### removeSslHostConfig

    public SSLHostConfig removeSslHostConfig(String hostName)
    Removes the SSL host configuration for the given host name, if such a configuration exists.
    Parameters:
      `hostName` - The host name associated with the SSL host configuration to remove
    Returns:
      The SSL host configuration that was removed, if any

  - ### reloadSslHostConfig

    public void reloadSslHostConfig(String hostName)
    Re-read the configuration files for the SSL host and replace the existing SSL configuration with the updated settings. Note this replacement will happen even if the settings remain unchanged.
    Parameters:
      `hostName` - The SSL host for which the configuration should be reloaded. This must match a current SSL host

  - ### reloadSslHostConfigs

    public void reloadSslHostConfigs()
    Re-read the configuration files for all SSL hosts and replace the existing SSL configuration with the updated settings. Note this replacement will happen even if the settings remain unchanged.

  - ### findSslHostConfigs

    public SSLHostConfig[] findSslHostConfigs()
    Find all SSL host configurations.
    Returns:
      An array of all SSL host configurations

  - ### createSSLContext

    protected abstract void createSSLContext(SSLHostConfig sslHostConfig) throws Exception
    Create the SSLContext for the given SSLHostConfig.
    Parameters:
      `sslHostConfig` - The SSLHostConfig for which the SSLContext should be created
    Throws:
      `Exception` - If the SSLContext cannot be created for the given SSLHostConfig

  - ### setDefaultSslHostConfig

    protected abstract void setDefaultSslHostConfig(SSLHostConfig sslHostConfig)

  - ### logCertificate

    protected void logCertificate(SSLHostConfigCertificate certificate)
    Log information about the given certificate.
    Parameters:
      `certificate` - The certificate to log information about

  - ### generateCertificateDebug

    protected String generateCertificateDebug(X509Certificate certificate)
    Generate debug information about a certificate.
    Parameters:
      `certificate` - The certificate to generate debug info for
    Returns:
      A string containing certificate debug information

  - ### destroySsl

    protected void destroySsl() throws Exception
    Destroy the SSL configuration.
    Throws:
      `Exception` - If an error occurs while destroying SSL

  - ### releaseSSLContext

    protected void releaseSSLContext(SSLHostConfig sslHostConfig)
    Release the SSLContext, if any, associated with the SSLHostConfig.
    Parameters:
      `sslHostConfig` - The SSLHostConfig for which the SSLContext should be released

  - ### getSSLHostConfig

    protected SSLHostConfig getSSLHostConfig(String sniHostName)
    Look up the SSLHostConfig for the given host name. Lookup order is:
    1. exact match
    2. wild card match
    3. default SSLHostConfig
    Parameters:
      `sniHostName` - Host name - must be in lower case
    Returns:
      The SSLHostConfig for the given host name.

  - ### checkSni

    public boolean checkSni(String sniHostName, String protocolHostName)
    Check if two host names share the same SSLHostConfig.
    Parameters:
      `sniHostName` - the host name from SNI, null if SNI is not in use
      `protocolHostName` - the host name from the protocol
    Returns:
      true if SNI is not checked, if the SNI host name matches the protocol host name, if both host names use the same SSLHostConfig configuration, if there is no SNI and the protocol host name uses the default SSLHostConfig configuration, and false otherwise

  - ### getUseSendfile

    public boolean getUseSendfile()
    Get the sendfile flag.
    Returns:
      True if sendfile is enabled

  - ### setUseSendfile

    public void setUseSendfile(boolean useSendfile)
    Set the sendfile flag.
    Parameters:
      `useSendfile` - True to enable sendfile

  - ### getExecutorTerminationTimeoutMillis

    public long getExecutorTerminationTimeoutMillis()
    Get the executor termination timeout.
    Returns:
      The executor termination timeout in milliseconds

  - ### setExecutorTerminationTimeoutMillis

    public void setExecutorTerminationTimeoutMillis(long executorTerminationTimeoutMillis)
    Set the executor termination timeout.
    Parameters:
      `executorTerminationTimeoutMillis` - The timeout in milliseconds

  - ### setAcceptorThreadCount

    @Deprecated public void setAcceptorThreadCount(int acceptorThreadCount)
    Deprecated.
    This attribute is hard-coded to `1` and is no longer configurable. This setter will be removed in Tomcat 10.
    Unused.
    Parameters:
      `acceptorThreadCount` - Ignored

  - ### getAcceptorThreadCount

    @Deprecated public int getAcceptorThreadCount()
    Deprecated.
    This attribute is hard-coded to `1` and is no longer configurable. This getter will be removed in Tomcat 10.
    Unused.
    Returns:
      Always returns `1`

  - ### setAcceptorThreadPriority

    public void setAcceptorThreadPriority(int acceptorThreadPriority)
    Set the acceptor thread priority.
    Parameters:
      `acceptorThreadPriority` - The thread priority

  - ### getAcceptorThreadPriority

    public int getAcceptorThreadPriority()
    Get the acceptor thread priority.
    Returns:
      The acceptor thread priority

  - ### setMaxConnections

    public void setMaxConnections(int maxCon)
    Set the maximum number of connections.
    Parameters:
      `maxCon` - The maximum number of connections (-1 for unlimited)

  - ### getMaxConnections

    public int getMaxConnections()
    Get the maximum number of connections.
    Returns:
      The maximum number of connections

  - ### getConnectionCount

    public long getConnectionCount()
    Return the current count of connections handled by this endpoint, if the connections are counted (which happens when the maximum count of connections is limited), or `-1` if they are not. This property is added here so that this value can be inspected through JMX. It is visible on "ThreadPool" MBean.

    The count is incremented by the Acceptor before it tries to accept a new connection. Until the limit is reached and thus the count cannot be incremented, this value is more by 1 (the count of acceptors) than the actual count of connections that are being served.

    Returns:
      The count

  - ### setExecutor

    public void setExecutor(Executor executor)
    Set the external executor.
    Parameters:
      `executor` - The external executor (null to use internal executor)

  - ### getExecutor

    public Executor getExecutor()
    Get the external executor.
    Returns:
      The external executor, or null if none is configured

  - ### setUseVirtualThreads

    public void setUseVirtualThreads(boolean useVirtualThreads)
    Set whether virtual threads should be used.
    Parameters:
      `useVirtualThreads` - True to use virtual threads

  - ### getUseVirtualThreads

    public boolean getUseVirtualThreads()
    Get whether virtual threads are enabled.
    Returns:
      True if virtual threads are enabled

  - ### setUtilityExecutor

    public void setUtilityExecutor(ScheduledExecutorService utilityExecutor)
    Set the utility executor.
    Parameters:
      `utilityExecutor` - The utility executor

  - ### getUtilityExecutor

    public ScheduledExecutorService getUtilityExecutor()
    Get the utility executor.
    Returns:
      The utility executor

  - ### getPort

    public int getPort()
    Get the server socket port.
    Returns:
      The server socket port

  - ### setPort

    public void setPort(int port)
    Set the server socket port.
    Parameters:
      `port` - The server socket port

  - ### getPortOffset

    public int getPortOffset()
    Get the port offset.
    Returns:
      The port offset

  - ### setPortOffset

    public void setPortOffset(int portOffset)
    Set the port offset.
    Parameters:
      `portOffset` - The port offset (must be >= 0)

  - ### getPortWithOffset

    public int getPortWithOffset()
    Get the port with offset applied.
    Returns:
      The port with offset, or the port if port <= 0

  - ### getLocalPort

    public final int getLocalPort()
    Get the local port the server socket is bound to.
    Returns:
      The local port or -1 if not bound

  - ### getAddress

    public InetAddress getAddress()
    Get the bind address.
    Returns:
      The bind address

  - ### setAddress

    public void setAddress(InetAddress address)
    Set the bind address.
    Parameters:
      `address` - The bind address

  - ### getLocalAddress

    protected abstract InetSocketAddress getLocalAddress() throws IOException
    Obtain the network address the server socket is bound to. This primarily exists to enable the correct address to be used when unlocking the server socket since it removes the guess-work involved if no address is specifically set.
    Returns:
      The network address that the server socket is listening on or null if the server socket is not currently bound.
    Throws:
      `IOException` - If there is a problem determining the currently bound socket

  - ### setAcceptCount

    public void setAcceptCount(int acceptCount)
    Set the accept count.
    Parameters:
      `acceptCount` - The accept count (must be > 0)

  - ### getAcceptCount

    public int getAcceptCount()
    Get the accept count.
    Returns:
      The accept count

  - ### getBindOnInit

    public boolean getBindOnInit()
    Get the bind on init flag.
    Returns:
      True if the endpoint binds on init, false if it binds on start

  - ### setBindOnInit

    public void setBindOnInit(boolean b)
    Set the bind on init flag.
    Parameters:
      `b` - True to bind on init, false to bind on start

  - ### getBindState

    protected AbstractEndpoint.BindState getBindState()
    Get the current bind state.
    Returns:
      The current bind state

  - ### getKeepAliveTimeout

    public int getKeepAliveTimeout()
    Get the keepalive timeout.
    Returns:
      The keepalive timeout in milliseconds

  - ### setKeepAliveTimeout

    public void setKeepAliveTimeout(int keepAliveTimeout)
    Set the keepalive timeout.
    Parameters:
      `keepAliveTimeout` - The keepalive timeout in milliseconds

  - ### getTcpNoDelay

    public boolean getTcpNoDelay()
    Socket TCP no delay.
    Returns:
      The current TCP no delay setting for sockets created by this endpoint

  - ### setTcpNoDelay

    public void setTcpNoDelay(boolean tcpNoDelay)
    Set the TCP no delay flag.
    Parameters:
      `tcpNoDelay` - True to enable TCP no delay

  - ### getConnectionLinger

    public int getConnectionLinger()
    Socket linger.
    Returns:
      The current socket linger time for sockets created by this endpoint

  - ### setConnectionLinger

    public void setConnectionLinger(int connectionLinger)
    Set the connection linger time.
    Parameters:
      `connectionLinger` - The socket linger time in seconds

  - ### getConnectionTimeout

    public int getConnectionTimeout()
    Socket timeout.
    Returns:
      The current socket timeout for sockets created by this endpoint

  - ### setConnectionTimeout

    public void setConnectionTimeout(int soTimeout)
    Set the connection timeout.
    Parameters:
      `soTimeout` - The socket timeout in milliseconds

  - ### isSSLEnabled

    public boolean isSSLEnabled()
    Check if SSL is enabled.
    Returns:
      True if SSL is enabled

  - ### setSSLEnabled

    public void setSSLEnabled(boolean SSLEnabled)
    Set the SSL enabled flag.
    Parameters:
      `SSLEnabled` - True to enable SSL

  - ### isAlpnSupported

    public abstract boolean isAlpnSupported()
    Identifies if the endpoint supports ALPN. Note that a return value of `true` implies that `isSSLEnabled()` will also return `true`.
    Returns:
      `true` if the endpoint supports ALPN in its current configuration, otherwise `false`.

  - ### setMinSpareThreads

    public void setMinSpareThreads(int minSpareThreads)
    Set the minimum number of spare threads.
    Parameters:
      `minSpareThreads` - The minimum number of spare threads

  - ### getMinSpareThreads

    public int getMinSpareThreads()
    Get the minimum number of spare threads.
    Returns:
      The minimum number of spare threads

  - ### setMaxThreads

    public void setMaxThreads(int maxThreads)
    Set the maximum number of worker threads.
    Parameters:
      `maxThreads` - The maximum number of worker threads

  - ### getMaxThreads

    public int getMaxThreads()
    Get the maximum number of worker threads.
    Returns:
      The maximum number of worker threads, or -1 if no internal executor is used

  - ### setMaxQueueSize

    public void setMaxQueueSize(int maxQueueSize)
    Set the maximum task queue size.
    Parameters:
      `maxQueueSize` - The maximum queue size

  - ### getMaxQueueSize

    public int getMaxQueueSize()
    Get the maximum queue size.
    Returns:
      The maximum queue size

  - ### setThreadsMaxIdleTime

    public void setThreadsMaxIdleTime(int threadsMaxIdleTime)
    Set the maximum idle time for threads in the internal thread pool.
    Parameters:
      `threadsMaxIdleTime` - The maximum idle time in milliseconds

  - ### getThreadsMaxIdleTime

    public int getThreadsMaxIdleTime()
    Get the maximum idle time for threads in the internal thread pool.
    Returns:
      The maximum idle time in milliseconds, or -1 if no internal executor is used

  - ### setThreadPriority

    public void setThreadPriority(int threadPriority)
    Set the priority of the worker threads.
    Parameters:
      `threadPriority` - The thread priority

  - ### getThreadPriority

    public int getThreadPriority()
    Get the priority of the worker threads.
    Returns:
      The thread priority, or -1 if no internal executor is used

  - ### getMaxKeepAliveRequests

    public int getMaxKeepAliveRequests()
    Get the maximum number of keep alive requests.
    Returns:
      The maximum number of keep alive requests

  - ### setMaxKeepAliveRequests

    public void setMaxKeepAliveRequests(int maxKeepAliveRequests)
    Set the maximum number of keep alive requests.
    Parameters:
      `maxKeepAliveRequests` - The maximum number of keep alive requests

  - ### setName

    public void setName(String name)
    Set the name of the thread pool.
    Parameters:
      `name` - The name of the thread pool

  - ### getName

    public String getName()
    Get the name of the thread pool.
    Returns:
      The name of the thread pool

  - ### setDomain

    public void setDomain(String domain)
    Set the domain for JMX registration.
    Parameters:
      `domain` - The JMX domain

  - ### getDomain

    public String getDomain()
    Get the JMX domain.
    Returns:
      The JMX domain, or null if not set

  - ### setDaemon

    public void setDaemon(boolean b)
    Set whether the threads should be daemon threads.
    Parameters:
      `b` - True to use daemon threads

  - ### getDaemon

    public boolean getDaemon()
    Check if the threads are daemon threads.
    Returns:
      True if the threads are daemon threads

  - ### setUseAsyncIO

    public void setUseAsyncIO(boolean useAsyncIO)
    Set whether asynchronous IO is enabled.
    Parameters:
      `useAsyncIO` - True to enable asynchronous IO

  - ### getUseAsyncIO

    public boolean getUseAsyncIO()
    Check if asynchronous IO is enabled.
    Returns:
      True if asynchronous IO is enabled

  - ### getDeferAccept

    protected abstract boolean getDeferAccept()

  - ### getId

    public String getId()
    The default behavior is to identify connectors uniquely with address and port. However, certain connectors are not using that and need some other identifier, which then can be used as a replacement.
    Returns:
      the id

  - ### addNegotiatedProtocol

    public void addNegotiatedProtocol(String negotiableProtocol)
    Add a protocol that can be negotiated (e.g. ALPN).
    Parameters:
      `negotiableProtocol` - The protocol to add

  - ### hasNegotiableProtocols

    public boolean hasNegotiableProtocols()
    Check if there are any negotiable protocols configured.
    Returns:
      True if there are negotiable protocols

  - ### setHandler

    public void setHandler(AbstractEndpoint.Handler<S> handler)
    Set the handler for this endpoint.
    Parameters:
      `handler` - The handler to set

  - ### getHandler

    public AbstractEndpoint.Handler<S> getHandler()
    Get the handler.
    Returns:
      The handler

  - ### setAttribute

    public void setAttribute(String name, Object value)
    Generic property setter called when a property for which a specific setter already exists within the `ProtocolHandler` needs to be made available to subcomponents. The specific setter will call this method to populate the attributes.
    Parameters:
      `name` - Name of property to set
      `value` - The value to set the property to

  - ### getAttribute

    public Object getAttribute(String key)
    Used by subcomponents to retrieve configuration information.
    Parameters:
      `key` - The name of the property for which the value should be retrieved
    Returns:
      The value of the specified property

  - ### setProperty

    public boolean setProperty(String name, String value)
    Set the specified property.
    Parameters:
      `name` - The name of the property
      `value` - The value of the property
    Returns:
      True if the property was set successfully

  - ### getProperty

    public String getProperty(String name)
    Get the value of the specified property.
    Parameters:
      `name` - The name of the property
    Returns:
      The value of the property, or null if not found

  - ### getCurrentThreadCount

    public int getCurrentThreadCount()
    Return the amount of threads that are managed by the pool.
    Returns:
      the amount of threads that are managed by the pool

  - ### getCurrentThreadsBusy

    public int getCurrentThreadsBusy()
    Return the amount of threads that are in use
    Returns:
      the amount of threads that are in use

  - ### isRunning

    public boolean isRunning()
    Check if the endpoint is running.
    Returns:
      True if the endpoint is running

  - ### isPaused

    public boolean isPaused()
    Check if the endpoint is paused.
    Returns:
      True if the endpoint is paused

  - ### createExecutor

    public void createExecutor()
    Create the internal executor.

  - ### shutdownExecutor

    public void shutdownExecutor()
    Shutdown the internal executor.

  - ### unlockAccept

    protected void unlockAccept()
    Unlock the server socket acceptor threads using bogus connections.

  - ### processSocket

    public boolean processSocket(SocketWrapperBase<S> socketWrapper, SocketEvent event, boolean dispatch)
    Process the given SocketWrapper with the given status. Used to trigger processing as if the Poller (for those endpoints that have one) selected the socket.
    Parameters:
      `socketWrapper` - The socket wrapper to process
      `event` - The socket event to be processed
      `dispatch` - Should the processing be performed on a new container thread
    Returns:
      if processing was triggered successfully

  - ### createSocketProcessor

    protected abstract SocketProcessorBase<S> createSocketProcessor(SocketWrapperBase<S> socketWrapper, SocketEvent event)
    Create a socket processor for the given socket wrapper.
    Parameters:
      `socketWrapper` - The socket wrapper to process
      `event` - The socket event
    Returns:
      The socket processor

  - ### bind

    public abstract void bind() throws Exception
    Bind the endpoint to its port and address.
    Throws:
      `Exception` - If an error occurs during binding

  - ### unbind

    public abstract void unbind() throws Exception
    Throws:
      `Exception`

  - ### startInternal

    public abstract void startInternal() throws Exception
    Start the endpoint internal components.
    Throws:
      `Exception` - If an error occurs during startup

  - ### stopInternal

    public abstract void stopInternal() throws Exception
    Stop the endpoint internal components.
    Throws:
      `Exception` - If an error occurs during shutdown

  - ### init

    public final void init() throws Exception
    Initialize the endpoint.
    Throws:
      `Exception` - If an error occurs during initialization

  - ### start

    public final void start() throws Exception
    Start the endpoint.
    Throws:
      `Exception` - If an error occurs during startup

  - ### startAcceptorThread

    protected void startAcceptorThread()
    Start the acceptor thread.

  - ### pause

    public void pause()
    Pause the endpoint, which will stop it accepting new connections and unlock the acceptor.

  - ### resume

    public void resume()
    Resume the endpoint, which will make it start accepting new connections again.

  - ### stop

    public final void stop() throws Exception
    Stop the endpoint.
    Throws:
      `Exception` - If an error occurs during shutdown

  - ### destroy

    public final void destroy() throws Exception
    Destroy the endpoint and release all resources.
    Throws:
      `Exception` - If an error occurs while destroying the endpoint

  - ### getLog

    protected abstract Log getLog()
    Get the logger for this endpoint.
    Returns:
      The logger

  - ### getLogCertificate

    protected Log getLogCertificate()
    Get the logger for certificate-related messages.
    Returns:
      The logger (defaults to `getLog()`)

  - ### initializeConnectionLatch

    protected LimitLatch initializeConnectionLatch()
    Initialize the connection latch if it has not already been created.
    Returns:
      The connection latch, or null if connection counting is disabled

  - ### countUpOrAwaitConnection

    protected void countUpOrAwaitConnection() throws InterruptedException
    Count up or await a connection slot.
    Throws:
      `InterruptedException` - If thrown during thread interruption

  - ### countDownConnection

    protected long countDownConnection()
    Count down a connection.
    Returns:
      The number of connections remaining, or -1 if connection counting is disabled

  - ### closeServerSocketGraceful

    public final void closeServerSocketGraceful()
    Close the server socket (to prevent further connections) if the server socket was originally bound on `start()` (rather than on `init()`).
    See Also:
      - `getBindOnInit()`

  - ### awaitConnectionsClose

    public final long awaitConnectionsClose(long waitMillis)
    Wait for the client connections to the server to close gracefully. The method will return when all of the client connections have closed or the method has been waiting for `waitTimeMillis`.
    Parameters:
      `waitMillis` - The maximum time to wait in milliseconds for the client connections to close.
    Returns:
      The wait time, if any remaining when the method returned

  - ### doCloseServerSocket

    protected abstract void doCloseServerSocket() throws IOException
    Actually close the server socket but don't perform any other clean-up.
    Throws:
      `IOException` - If an error occurs closing the socket

  - ### serverSocketAccept

    protected abstract U serverSocketAccept() throws Exception
    Accept a connection from the server socket.
    Returns:
      The accepted socket
    Throws:
      `Exception` - If an error occurs during accept

  - ### setSocketOptions

    protected abstract boolean setSocketOptions(U socket)
    Set the socket options for the given accepted socket.
    Parameters:
      `socket` - The accepted socket
    Returns:
      True if the socket options were set successfully

  - ### closeSocket

    protected void closeSocket(U socket)
    Close the socket when the connection has to be immediately closed when an error occurs while configuring the accepted socket or trying to dispatch it for processing. The wrapper associated with the socket will be used for the close.
    Parameters:
      `socket` - The newly accepted socket

  - ### destroySocket

    protected abstract void destroySocket(U socket)
    Close the socket. This is used when the connector is not in a state which allows processing the socket, or if there was an error which prevented the allocation of the socket wrapper.
    Parameters:
      `socket` - The newly accepted socket