Record Class KeepAliveMessage

java.lang.Object
java.lang.Record
pt.unl.fct.di.novasys.babel2.channels.messages.KeepAliveMessage
All Implemented Interfaces:
BabelMessage
public record KeepAliveMessage() extends Record implements BabelMessage
Singleton message sent periodically over QUIC connections to prevent the underlying QUIC session from timing out due to inactivity.

The QUICHandshakeHandler installs a Netty IdleStateHandler on each QUIC channel after a successful handshake. When 20 seconds of write-idle time pass without any application message, it calls QUICBabelChannel.keepAlivePing(BabelNode) which sends this message. The receiving side discards it silently via QUICKeepAliveHandler.

The message is assigned the reserved ID -1 and carries no payload. Use the shared INSTANCE constant rather than constructing new instances.

  • Field Summary

    Fields
    Modifier and Type
    Field
    Description
    static final KeepAliveMessage
    INSTANCE
    Shared singleton instance; always use this instead of creating new objects.
    static final int
    KEEP_ALIVE_SIGNAL
    Magic signal value used to identify this message type on the wire.

  • Constructor Summary

    Constructors
    Constructor
    Description
    KeepAliveMessage()
    Creates an instance of a KeepAliveMessage record class.

  • Method Summary

    Modifier and Type
    Method
    Description
    final boolean
    equals(Object o)
    Indicates whether some other object is "equal to" this one.
    final int
    hashCode()
    Returns a hash code value for this object.
    final String
    toString()
    Returns a string representation of this record class.

    Methods inherited from class Object

    clone, finalize, getClass, notify, notifyAll, wait, wait, wait

  • Field Details

    • INSTANCE

      public static final KeepAliveMessage INSTANCE
      Shared singleton instance; always use this instead of creating new objects.

    • KEEP_ALIVE_SIGNAL

      public static final int KEEP_ALIVE_SIGNAL
      Magic signal value used to identify this message type on the wire. Equals the Unicode code point for U+1F44C (OK hand sign).
      See Also:

  • Constructor Details

    • KeepAliveMessage

      public KeepAliveMessage()
      Creates an instance of a KeepAliveMessage record class.

  • Method Details

    • toString

      public final String toString()
      Returns a string representation of this record class. The representation contains the name of the class, followed by the name and value of each of the record components.
      Specified by:
      toString in class Record
      Returns:
      a string representation of this object

    • hashCode

      public final int hashCode()
      Returns a hash code value for this object. The value is derived from the hash code of each of the record components.
      Specified by:
      hashCode in class Record
      Returns:
      a hash code value for this object

    • equals

      public final boolean equals(Object o)
      Indicates whether some other object is "equal to" this one. The objects are equal if the other object is of the same class and if all the record components are equal.
      Specified by:
      equals in class Record
      Parameters:
      o - the object with which to compare
      Returns:
      true if this object is the same as the o argument; false otherwise.