Package eu.ill.webx

Class WebXTunnel

java.lang.Object
eu.ill.webx.WebXTunnel
public class WebXTunnel extends Object
The WebXTunnel provides the main entry point to connecting to a WebX Host. Session creation and client connection is handled through the connect method. Each client connected to the relay has an individual tunnel through which instructions can be passed to the WebX Engine and messages can be read from the engine.

  • Constructor Details

    • WebXTunnel

      public WebXTunnel()
      Default constructor of a tunnel

  • Method Details

    • Connect

      public static WebXTunnel Connect(WebXHostConfiguration hostConfiguration, WebXClientConfiguration clientConfiguration) throws WebXConnectionException
      Static method to create a WebXTunnel, connect to the host and create a client.
      Parameters:
      hostConfiguration - Configuration for the WebX Host (eg hostname and port)
      clientConfiguration - Configuration for the client (login parameters or session Id)
      Returns:
      a connected WebXTunnel
      Throws:
      WebXConnectionException - thrown if the connection fails

    • connect

      public void connect(WebXHostConfiguration hostConfiguration, WebXClientConfiguration clientConfiguration) throws WebXConnectionException
      Connects to a WebX Engine on a specific host/port and connects the client to a WebX Session. The connection parameters determine whether a new session is created or connection is required to a session that is already running.
      Parameters:
      hostConfiguration - Configuration for the WebX Host (eg hostname and port)
      clientConfiguration - Configuration for the client (login parameters or session Id)
      Throws:
      WebXConnectionException - thrown if the connection fails

    • getConnectionId

      public String getConnectionId() throws WebXClientException
      Returns the connection Id of the client: corresponds to the session Id of the WebX Engine
      Returns:
      The connection Id of the client: corresponds to the session Id of the WebX Engine
      Throws:
      WebXClientException - thrown if the tunnel is not connected

    • disconnect

      public void disconnect()
      Disconnects the client from the WebX Session: message sent to the WebX Engine do disconnect the client. Client removed from the session. Session closed if no more connected clients (session pinging will be halted accordingly) Host disconnected if no sessions are running on the specific host.

    • isConnected

      public boolean isConnected()
      Returns true if the client is connected
      Returns:
      True if the client is connected.

    • read

      public byte[] read() throws WebXClientException, WebXConnectionInterruptException, WebXDisconnectedException
      Blocking call to get next message from the Client. The client stores all messages in a queue liberating the ZMQ thread as quickly as possible. Client applications must read the messages from the queue and send them to the client. The read method is blocking and returns only when a message is available.
      Returns:
      The byte array data for the next message
      Throws:
      WebXClientException - thrown when an error occurs with the client or if an error is detected in the message data
      WebXConnectionInterruptException - thrown when the read is interrupted for example the session doesn't respond to a ping
      WebXDisconnectedException - thrown when the client is disconnected from the server

    • write

      public void write(byte[] payload) throws WebXClientException
      Writes data to the WebX Engine, sending instructions from the client. The instruction is queued and the client thread is liberated quickly. Instruction headers are automatically modified to include the session Id and the Client Id so that they are correctly routed and controlled in the server.
      Parameters:
      payload - The instruction data to send to the WebX Engine.
      Throws:
      WebXClientException - Thrown if the client is in error