Package jmri.jmrix

Class NetMessage

  • All Implemented Interfaces:
    Direct Known Subclasses:

    public abstract class NetMessage
    extends java.lang.Object
    Represents a single general command or response.

    Content is represented with ints to avoid the problems with sign-extension that bytes have, and because a Java char is actually a variable number of bytes in Unicode.

    Both a set of indexed contents, an opcode, and a length field are available. Different implementations will map the opcode and length into the contents in different ways. They may not appear at all...

    See Also:
    Serialized Form
    • Constructor Summary

      Constructor Description
      NetMessage​(int len)
      Create a new object, representing a specific-length message.
    • Constructor Detail

      • NetMessage

        public NetMessage​(int len)
        Create a new object, representing a specific-length message.
        len - Total bytes in message, including opcode and error-detection byte.
    • Method Detail

      • setOpCode

        public void setOpCode​(int i)
      • getOpCodeHex

        public java.lang.String getOpCodeHex()
        Get a String representation of the op code in hex.
        string of Opcode, 0x format.
      • getNumDataElements

        public int getNumDataElements()
        Get length, including op code and error-detection byte
        total number of data elements.
      • setElement

        public void setElement​(int n,
                               int v)
      • toString

        public java.lang.String toString()
        Get a String representation of the entire message in hex. This is not intended to be human-readable!
        toString in class java.lang.Object
      • checkParity

        public abstract boolean checkParity()
        check whether the message has a valid parity
        true if parity valid, else false.
      • setParity

        public abstract void setParity()
        Set parity to be correct for this implementation. Note that parity is really a stand-in for whatever error checking, etc needs to be done
      • lowByte

        protected static int lowByte​(int val)
      • highByte

        protected static int highByte​(int val)