Package org.apache.commons.net.telnet

Class TelnetOptionHandler

java.lang.Object
org.apache.commons.net.telnet.TelnetOptionHandler
Direct Known Subclasses:
EchoOptionHandler, SimpleOptionHandler, SuppressGAOptionHandler, TerminalTypeOptionHandler, WindowSizeOptionHandler
public abstract class TelnetOptionHandler extends Object
The TelnetOptionHandler class is the base class to be used for implementing handlers for telnet options.

TelnetOptionHandler implements basic option handling functionality and defines abstract methods that must be implemented to define subnegotiation behavior.

  • Field Summary

    Fields
    Modifier and Type
    Field
    Description
    private boolean
    acceptLocal
    true if the option should be accepted on the local side
    private boolean
    acceptRemote
    true if the option should be accepted on the remote side
    private boolean
    doFlag
    true if the option is active on the local side
    private boolean
    initialLocal
    true if the option should be activated on the local side
    private boolean
    initialRemote
    true if the option should be activated on the remote side
    private int
    optionCode
    Option code
    private boolean
    willFlag
    true if the option is active on the remote side

  • Constructor Summary

    Constructors
    Constructor
    Description
    TelnetOptionHandler(int optcode, boolean initlocal, boolean initremote, boolean acceptlocal, boolean acceptremote)
    Constructor for the TelnetOptionHandler.

  • Method Summary

    Modifier and Type
    Method
    Description
    int[]
    answerSubnegotiation(int[] suboptionData, int suboptionLength)
    Method called upon reception of a subnegotiation for this option coming from the other end.
    boolean
    getAcceptLocal()
    Gets a boolean indicating whether to accept a DO request coming from the other end.
    boolean
    getAcceptRemote()
    Gets a boolean indicating whether to accept a WILL request coming from the other end.
    (package private) boolean
    getDo()
    Gets a boolean indicating whether a DO request sent to the other side has been acknowledged.
    boolean
    getInitLocal()
    Gets a boolean indicating whether to send a WILL request to the other end upon connection.
    boolean
    getInitRemote()
    Gets a boolean indicating whether to send a DO request to the other end upon connection.
    int
    getOptionCode()
    Gets the option code for this option.
    (package private) boolean
    getWill()
    Gets a boolean indicating whether a WILL request sent to the other side has been acknowledged.
    void
    setAcceptLocal(boolean accept)
    Sets behavior of the option for DO requests coming from the other end.
    void
    setAcceptRemote(boolean accept)
    Sets behavior of the option for WILL requests coming from the other end.
    (package private) void
    setDo(boolean state)
    Sets this option whether a DO request sent to the other side has been acknowledged (invoked by TelnetClient).
    void
    setInitLocal(boolean init)
    Sets this option whether to send a WILL request upon connection.
    void
    setInitRemote(boolean init)
    Sets this option whether to send a DO request upon connection.
    (package private) void
    setWill(boolean state)
    Sets this option whether a WILL request sent to the other side has been acknowledged (invoked by TelnetClient).
    int[]
    startSubnegotiationLocal()
    This method is invoked whenever this option is acknowledged active on the local end (TelnetClient sent a WILL, remote side sent a DO).
    int[]
    startSubnegotiationRemote()
    This method is invoked whenever this option is acknowledged active on the remote end (TelnetClient sent a DO, remote side sent a WILL).

    Methods inherited from class java.lang.Object

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

  • Field Details

    • optionCode

      private int optionCode
      Option code

    • initialLocal

      private boolean initialLocal
      true if the option should be activated on the local side

    • initialRemote

      private boolean initialRemote
      true if the option should be activated on the remote side

    • acceptLocal

      private boolean acceptLocal
      true if the option should be accepted on the local side

    • acceptRemote

      private boolean acceptRemote
      true if the option should be accepted on the remote side

    • doFlag

      private boolean doFlag
      true if the option is active on the local side

    • willFlag

      private boolean willFlag
      true if the option is active on the remote side

  • Constructor Details

    • TelnetOptionHandler

      public TelnetOptionHandler(int optcode, boolean initlocal, boolean initremote, boolean acceptlocal, boolean acceptremote)
      Constructor for the TelnetOptionHandler. Allows defining desired initial setting for local/remote activation of this option and behavior in case a local/remote activation request for this option is received.
      Parameters:
      optcode - - Option code.
      initlocal - - if set to true, a WILL is sent upon connection.
      initremote - - if set to true, a DO is sent upon connection.
      acceptlocal - - if set to true, any DO request is accepted.
      acceptremote - - if set to true, any WILL request is accepted.

  • Method Details

    • answerSubnegotiation

      public int[] answerSubnegotiation(int[] suboptionData, int suboptionLength)
      Method called upon reception of a subnegotiation for this option coming from the other end.

      This implementation returns null, and must be overridden by the actual TelnetOptionHandler to specify which response must be sent for the subnegotiation request.

      Parameters:
      suboptionData - - the sequence received, without IAC SB & IAC SE
      suboptionLength - - the length of data in suboption_data
      Returns:
      response to be sent to the subnegotiation sequence. TelnetClient will add IAC SB & IAC SE. null means no response

    • getAcceptLocal

      public boolean getAcceptLocal()
      Gets a boolean indicating whether to accept a DO request coming from the other end.
      Returns:
      true if a DO request shall be accepted.

    • getAcceptRemote

      public boolean getAcceptRemote()
      Gets a boolean indicating whether to accept a WILL request coming from the other end.
      Returns:
      true if a WILL request shall be accepted.

    • getDo

      boolean getDo()
      Gets a boolean indicating whether a DO request sent to the other side has been acknowledged.
      Returns:
      true if a DO sent to the other side has been acknowledged.

    • getInitLocal

      public boolean getInitLocal()
      Gets a boolean indicating whether to send a WILL request to the other end upon connection.
      Returns:
      true if a WILL request shall be sent upon connection.

    • getInitRemote

      public boolean getInitRemote()
      Gets a boolean indicating whether to send a DO request to the other end upon connection.
      Returns:
      true if a DO request shall be sent upon connection.

    • getOptionCode

      public int getOptionCode()
      Gets the option code for this option.
      Returns:
      Option code.

    • getWill

      boolean getWill()
      Gets a boolean indicating whether a WILL request sent to the other side has been acknowledged.
      Returns:
      true if a WILL sent to the other side has been acknowledged.

    • setAcceptLocal

      public void setAcceptLocal(boolean accept)
      Sets behavior of the option for DO requests coming from the other end.
      Parameters:
      accept - - if true, subsequent DO requests will be accepted.

    • setAcceptRemote

      public void setAcceptRemote(boolean accept)
      Sets behavior of the option for WILL requests coming from the other end.
      Parameters:
      accept - - if true, subsequent WILL requests will be accepted.

    • setDo

      void setDo(boolean state)
      Sets this option whether a DO request sent to the other side has been acknowledged (invoked by TelnetClient).
      Parameters:
      state - - if true, a DO request has been acknowledged.

    • setInitLocal

      public void setInitLocal(boolean init)
      Sets this option whether to send a WILL request upon connection.
      Parameters:
      init - - if true, a WILL request will be sent upon subsequent connections.

    • setInitRemote

      public void setInitRemote(boolean init)
      Sets this option whether to send a DO request upon connection.
      Parameters:
      init - - if true, a DO request will be sent upon subsequent connections.

    • setWill

      void setWill(boolean state)
      Sets this option whether a WILL request sent to the other side has been acknowledged (invoked by TelnetClient).
      Parameters:
      state - - if true, a WILL request has been acknowledged.

    • startSubnegotiationLocal

      public int[] startSubnegotiationLocal()
      This method is invoked whenever this option is acknowledged active on the local end (TelnetClient sent a WILL, remote side sent a DO). The method is used to specify a subnegotiation sequence that will be sent by TelnetClient when the option is activated.

      This implementation returns null, and must be overriden by the actual TelnetOptionHandler to specify which response must be sent for the subnegotiation request.

      Returns:
      subnegotiation sequence to be sent by TelnetClient. TelnetClient will add IAC SB & IAC SE. null means no subnegotiation.

    • startSubnegotiationRemote

      public int[] startSubnegotiationRemote()
      This method is invoked whenever this option is acknowledged active on the remote end (TelnetClient sent a DO, remote side sent a WILL). The method is used to specify a subnegotiation sequence that will be sent by TelnetClient when the option is activated.

      This implementation returns null, and must be overridden by the actual TelnetOptionHandler to specify which response must be sent for the subnegotiation request.

      Returns:
      subnegotiation sequence to be sent by TelnetClient. TelnetClient will add IAC SB & IAC SE. null means no subnegotiation.