Package org.littleshoot.proxy.impl

Class ServerGroup

java.lang.Object
org.littleshoot.proxy.impl.ServerGroup
public class ServerGroup extends Object
Manages thread pools for one or more proxy server instances. When servers are created, they must register with the ServerGroup using registerProxyServer(HttpProxyServer), and when they shut down, must unregister with the ServerGroup using unregisterProxyServer(HttpProxyServer, boolean).

  • Field Details

    • log

      private static final org.slf4j.Logger log

    • DEFAULT_INCOMING_ACCEPTOR_THREADS

      public static final int DEFAULT_INCOMING_ACCEPTOR_THREADS
      The default number of threads to accept incoming requests from clients. (Requests are serviced by worker threads, not acceptor threads.)
      See Also:

    • DEFAULT_INCOMING_WORKER_THREADS

      public static final int DEFAULT_INCOMING_WORKER_THREADS
      The default number of threads to service incoming requests from clients.
      See Also:

    • DEFAULT_OUTGOING_WORKER_THREADS

      public static final int DEFAULT_OUTGOING_WORKER_THREADS
      The default number of threads to service outgoing requests to servers.
      See Also:

    • serverGroupCount

      private static final AtomicInteger serverGroupCount
      Global counter for the serverGroupId.

    • name

      private final String name
      A name for this ServerGroup to use in naming threads.

    • serverGroupId

      private final int serverGroupId
      The ID of this server group. Forms part of the name of each thread created for this server group. Useful for differentiating threads when multiple proxy instances are running.

    • incomingAcceptorThreads

      private final int incomingAcceptorThreads

    • incomingWorkerThreads

      private final int incomingWorkerThreads

    • outgoingWorkerThreads

      private final int outgoingWorkerThreads

    • registeredServers

      public final List<HttpProxyServer> registeredServers
      List of all servers registered to use this ServerGroup. Any access to this list should be synchronized using the SERVER_REGISTRATION_LOCK.

    • protocolThreadPools

      private final EnumMap<TransportProtocol,ProxyThreadPools> protocolThreadPools
      A mapping of TransportProtocols to their initialized ProxyThreadPools. Each transport uses a different thread pool, since the initialization parameters are different.

    • TRANSPORT_PROTOCOL_SELECTOR_PROVIDERS

      private static final EnumMap<TransportProtocol,SelectorProvider> TRANSPORT_PROTOCOL_SELECTOR_PROVIDERS
      A mapping of selector providers to transport protocols. Avoids special-casing each transport protocol during transport protocol initialization.

    • stopped

      private final AtomicBoolean stopped
      True when this ServerGroup is stopped.

    • THREAD_POOL_INIT_LOCK

      private final Object THREAD_POOL_INIT_LOCK
      Lock for initializing any transport protocols.

    • SERVER_REGISTRATION_LOCK

      private final Object SERVER_REGISTRATION_LOCK
      Lock controlling access to the registerProxyServer(HttpProxyServer) and unregisterProxyServer(HttpProxyServer, boolean) methods.

  • Constructor Details

    • ServerGroup

      public ServerGroup(String name, int incomingAcceptorThreads, int incomingWorkerThreads, int outgoingWorkerThreads)
      Creates a new ServerGroup instance for a proxy. Threads created for this ServerGroup will have the specified ServerGroup name in the Thread name. This constructor does not actually initialize any thread pools; instead, thread pools for specific transport protocols are lazily initialized as needed.
      Parameters:
      name - ServerGroup name to include in thread names
      incomingAcceptorThreads - number of acceptor threads per protocol
      incomingWorkerThreads - number of client-to-proxy worker threads per protocol
      outgoingWorkerThreads - number of proxy-to-server worker threads per protocol

  • Method Details

    • getThreadPoolsForProtocol

      private ProxyThreadPools getThreadPoolsForProtocol(TransportProtocol protocol)
      Retrieves the ProxyThreadPools for the specified transport protocol. Lazily initializes the thread pools for the transport protocol if they have not yet been initialized. If the protocol has already been initialized, this method returns immediately, without synchronization. If initialization is necessary, the initialization process creates the acceptor and worker threads necessary to service requests to/from the proxy.

      This method is thread-safe; no external locking is necessary.

      Parameters:
      protocol - transport protocol to retrieve thread pools for
      Returns:
      thread pools for the specified transport protocol

    • registerProxyServer

      public void registerProxyServer(HttpProxyServer proxyServer)
      Registers the specified proxy server as a consumer of this server group. The server group will not be shut down until the proxy unregisters itself.
      Parameters:
      proxyServer - proxy server instance to register

    • unregisterProxyServer

      public void unregisterProxyServer(HttpProxyServer proxyServer, boolean graceful)
      Unregisters the specified proxy server from this server group. If this was the last registered proxy server, the server group will be shut down.
      Parameters:
      proxyServer - proxy server instance to unregister
      graceful - when true, the server group shutdown (if necessary) will be graceful

    • shutdown

      private void shutdown(boolean graceful)
      Shuts down all event loops owned by this server group.
      Parameters:
      graceful - when true, event loops will "gracefully" terminate, waiting for submitted tasks to finish

    • getClientToProxyAcceptorPoolForTransport

      public EventLoopGroup getClientToProxyAcceptorPoolForTransport(TransportProtocol protocol)
      Retrieves the client-to-proxy acceptor thread pool for the specified protocol. Initializes the pool if it has not yet been initialized.

      This method is thread-safe; no external locking is necessary.

      Parameters:
      protocol - transport protocol to retrieve the thread pool for
      Returns:
      the client-to-proxy acceptor thread pool

    • getClientToProxyWorkerPoolForTransport

      public EventLoopGroup getClientToProxyWorkerPoolForTransport(TransportProtocol protocol)
      Retrieves the client-to-proxy acceptor worker pool for the specified protocol. Initializes the pool if it has not yet been initialized.

      This method is thread-safe; no external locking is necessary.

      Parameters:
      protocol - transport protocol to retrieve the thread pool for
      Returns:
      the client-to-proxy worker thread pool

    • getProxyToServerWorkerPoolForTransport

      public EventLoopGroup getProxyToServerWorkerPoolForTransport(TransportProtocol protocol)
      Retrieves the proxy-to-server worker thread pool for the specified protocol. Initializes the pool if it has not yet been initialized.

      This method is thread-safe; no external locking is necessary.

      Parameters:
      protocol - transport protocol to retrieve the thread pool for
      Returns:
      the proxy-to-server worker thread pool

    • isStopped

      public boolean isStopped()
      Returns:
      true if this ServerGroup has already been stopped