Class COMPRESS


  • public class COMPRESS
    extends Protocol
    Compresses the payload of a message. Goal is to reduce the number of messages sent across the wire. Should ideally be layered somewhere above a fragmentation protocol (e.g. FRAG).
    Version:
    $Id: COMPRESS.java,v 1.19.4.1 2008/11/28 06:08:35 belaban Exp $
    Author:
    Bela Ban
    • Constructor Detail

      • COMPRESS

        public COMPRESS()
    • Method Detail

      • getName

        public java.lang.String getName()
        Specified by:
        getName in class Protocol
      • init

        public void init()
                  throws java.lang.Exception
        Description copied from class: Protocol
        Called after instance has been created (null constructor) and before protocol is started. Properties are already set. Other protocols are not yet connected and events cannot yet be sent.
        Overrides:
        init in class Protocol
        Throws:
        java.lang.Exception - Thrown if protocol cannot be initialized successfully. This will cause the ProtocolStack to fail, so the channel constructor will throw an exception
      • destroy

        public void destroy()
        Description copied from class: Protocol
        This method is called on a Channel.close(). Does some cleanup; after the call the VM will terminate
        Overrides:
        destroy in class Protocol
      • setProperties

        public boolean setProperties​(java.util.Properties props)
        Description copied from class: Protocol
        Configures the protocol initially. A configuration string consists of name=value items, separated by a ';' (semicolon), e.g.:
         "loopback=false;unicast_inport=4444"
         
        Overrides:
        setProperties in class Protocol
      • down

        public java.lang.Object down​(Event evt)
        We compress the payload if it is larger than min_size. In this case we add a header containing the original size before compression. Otherwise we add no header.
        Note that we compress either the entire buffer (if offset/length are not used), or a subset (if offset/length are used)
        Overrides:
        down in class Protocol
        Parameters:
        evt -
      • up

        public java.lang.Object up​(Event evt)
        If there is no header, we pass the message up. Otherwise we uncompress the payload to its original size.
        Overrides:
        up in class Protocol
        Parameters:
        evt -