trawlernodearpcommands.java

source code for fishnet

import java.net.InetAddress;
import java.util.ArrayList;

/**
 * <pre>   
 * Provides method to create and parse commands sent between the Trawler and the emulated node
 * </pre>   
 */
public class TrawlerNodeARPCommands {

    /**
     * Return a command to add a neighbor.
     * @param fishAddr Fishnet address of neighbor
     * @param ipAddress IP Address of neighbor
     * @param port Port the neighbor is using for communication with peers
     * @return A command to add a neighbor.
     */
    public static String addNeighbor(int fishAddr, InetAddress ipAddress, int port) {
	String cmd = "add " + String.valueOf(fishAddr) + " ";
	cmd += ipAddress.getHostName() + " " + String.valueOf(port);	
	return cmd;     
    }

    /**
     * Return a command to remove a neighbor
     * @param fishAddr Fishnet address of neighbor to remove
     * @return A command to remove a neighbor
     */
    public static String removeNeighbor(int fishAddr) {
	return new String("remove " + String.valueOf(fishAddr));
    }

    /**
     * Return a command to reset a node
     * @return A command to reset a node
     */
    public static String reset() {
	return new String("reset");
    }

    /**
     * Parse an addNeighbor command.
     * @param cmd The command received
     * @param data An ArrayList that will be populated with the data if this is an addNeighbor command. 
     *             data[0] = fishned address and data[1] = EmulatorARPData. 
     * @return True if this was an addNeighbor command
     */
    public static boolean receiveAddNeighbor(String cmd, ArrayList data) {
	String[] args = cmd.split(" ");
	if(args.length != 4 || !args[0].equals("add")) {
	    return false;
	} 
	try {
	    Integer fishAddr = Integer.valueOf(args[1]);
	    InetAddress ipAddress = InetAddress.getByName(args[2]);
	    int port = Integer.parseInt(args[3]);
	    data.add(fishAddr);
	    data.add(new EmulatorARPData(ipAddress, port));
	    return true;
	}catch(Exception e) {
	    // Do nothing. Will return false
	}
	return false;
    }

    /**
     * Parse a removeNeighbor command
     * @param cmd The command received
     * @return The address of the node to remove. -1 if this was not a removeNeighbor command
     */
    public static int receiveRemoveNeighbor(String cmd) {
	String[] args = cmd.split(" ");
	if(args.length != 2 || !args[0].equals("remove")) {
	    return -1;
	}
	try {
	    return Integer.parseInt(args[1]);
	}catch(Exception e) {
	    //Do nothing. Will return -1
	}
	return -1;
    }

    /**
     * Parse a reset command
     * @param cmd The command seen
     * @return True if this was a reset command
     */
    public static boolean receiveReset(String cmd) {
	return cmd.equals("reset");
    }
}