node.java

一个p2p仿真软件

/**
 * @(#)Node.java	ver 1.2  6/20/2005
 *
 * Modified by Weishuai Yang ([e-mail]). 
 * 
 * this file is based on KOM / LetsQoS Topology Conversion Tools
 */

package gps.network.graph;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.logging.Logger;

import gps.event.SimEvent;
import gps.event.SimEventHandler;
import gps.network.Topology;
import gps.protocol.Agent;

/**
 * Represents a network node. 
 * To get and change the properties of the node call node.getProperties().
 * @author Oliver Heckmann
 */
public class Node implements SimEventHandler {


	/**
	 * singleton reference to topology
	 */
	protected static Topology mTopology=Topology.getInstance();
	/**
	 * singleton reference to debug log
	 */
	protected static Logger mDebugLog = Logger.getLogger("Debug");
	
	/**
	 * provide next available id for automatically indexing
	 */
	public static int mNextAvailableID = 0;
	
	/**
	 * mNodeID decides the position in Node[] list
	 */
	protected int mNodeID = 0;
	
	/**
	 * activate status
	 */
	protected boolean mActivated = true;

	/**
	 * agents attached on this node
	 */
	protected ArrayList mAgentList=new ArrayList(1);

	/**
	 * links connected with this node
	 */
	protected HashMap mLinks=new HashMap(1);


	/**
	 * node properties
	 */
	protected NodeProperties preProperties = new NodeProperties();

	/**
	 * reset values
	 */
	public void reset(){
		mActivated = true;
		mAgentList.clear();
	}

	// *********** Constructors
	/** Creates new Node, standard constructor.	 */
	public Node(){
		this(mNextAvailableID++);
	}
	
	
	/**
	 * initialization with specified node id
	 * 
	 * @param i node id
	 */	
	 
	public Node(int i){
		setID(i);
	}

	/**
	 * set id
	 * @param i new id
	 */
	public void setID(int i){
		mNodeID=i;
		if(i+1>mNextAvailableID)
			mNextAvailableID=i+1;
	}


	/**
	 * gets node id
	 * 
	 * @return node id
	 */
	public int getID(){
		return mNodeID;
	}
	
	/**
	 * gets node id
	 * @return node id
	 */
	public int getKey() {
		return getID();
		//return key;
	}
	/**
	 * set id
	 * @param key new id
	 */
	protected void setKey(int key) {
		setID(key);
		//this.key = key;
	}

	// ************ Properties

	/**
	 * gets node properties
	 * @return node properties
	 */
	public NodeProperties getProperties() {
		return preProperties;
	}

	/**
	 * sets node propertes
	 * @param p node properties
	 */
	public void setProperties(NodeProperties p) {
		this.preProperties = p;
	}

	/**
	 * gets agent list attached on this node
	 */
	public ArrayList getAgentList(){
		return mAgentList;
	}

	/**
	 * add a link between this node and another node
	 * @param n another node
	 * @param l link between two nodes
	 */
	public void hasLinkTo(Node n, Link l){
		mLinks.put(n,l);
	}

	/**
	 * gets link to another node
	 * @param n destination node
	 * @return link
	 */
	public Link getLinkTo(Node n){
		return (Link)mLinks.get(n);
	}
	
	/**
	 * checks activity
	 * 
	 * @return true if activated
	 */
	public boolean isActive(){
		return mActivated;
	}
	
	/**
	 * handles node level event
	 *
	 * @param e is the event to be handled
	 * @return true if already handled
	 * 
	 */
	public boolean handle(SimEvent e){
		if(e.getType()==SimEvent.SIM_NODE_ACTIVE) {
			//make this node active
			mActivated=true;
			return true;
		}
		else if(e.getType()==SimEvent.SIM_NODE_DEACTIVE) {
			//make this node inactive
			mActivated=false;
			return true;
		}
		return false;
	};


	/**
	 * attachs agents on that node
	 *
	 * @param a the agent to be attached
	 * 
	 */
	public void attach(Agent a){
		mAgentList.add(a);
	}
	/**
	 * gets string description
	 *
	 * @return string description
	 *
	 */


	public String toString() {
		String ret = "Node("+mNodeID+")";
		if (getProperties() != null) {
			ret += ": x="
				+ getProperties().getX()
				+ ", y="
				+ getProperties().getY()
				+ ", type="
				+ getProperties().getType();
		}
		return ret;
	}

}