link.java

p2p仿真

/**
 * @(#)Link.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 gps.network.BandwidthManager;


/**
 * Represents a link between to nodes. 
 * Can be directed (= unidirectional) or undirected (bidirectional, standard).
 * The link has some properties that can be read with link.getProperties().
 * @author Oliver Heckmann
 */
public class Link {
    /**
     * source node id
     */
    int fromNode = -1;
    /**
     * destination id
     */
    int toNode = -1;

    /**
     * bandwidth manager for this link
     */
	protected BandwidthManager mBM = null;

	/**
	 * link properties
	 */
    protected LinkProperties preProperties = new LinkProperties();


    
    /** Creates new Link, standard constructor 
     * @param directed directed or undirected 
     * @param fromNode source node
     * @param toNode destination node
     * 
     */
    public Link(boolean directed, int fromNode, int toNode) {
        this.fromNode = fromNode;
        this.toNode = toNode;
        preProperties.unidirectional = directed;
        mBM=new BandwidthManager(this);
    }

    /**
     * reset values
     *
     */
	public void reset(){
		mBM.reset();
	}
    
	/**
	 * gets string description
	 * @return string description
	 */
    public String toString() {
        String ret = "link from " + fromNode + " to " + toNode;
        /*
        LinkProperties p = getProperties();
        if (p != null) {
            ret += ": bw=" + p.getBandwidth();
        }
        */
        return ret;
    }
    
    /**
     * gets source node
     * @return source node
     */
    public int fromNode() {
        return fromNode;
    }
    
    /**
     * gets destination node
     * @return destination node
     */
    public int toNode() {
        return toNode;
    }
    
    /**
     * exchange source node and destination node
     *
     */
    public void turnaround() {
        int tmp;
        tmp = toNode; toNode = fromNode; fromNode = tmp;
    }
    
    /**
     * gets link properties
     * @return link properties
     */
    public LinkProperties getProperties() {
        return preProperties;
    }
    
    /**
     * check directed information
     * @return true if directed, otherwise false
     */
    public boolean isDirected() {
        return preProperties.unidirectional;
    }
    
    /**
     * sets bandwidth for this link
     * @param b new bandwidth
     */
    public void setBandwidth(double b){
    	mBM.setBandwidth(b);
    	preProperties.setBandwidth(b);
    }

    /**
     * sets delay for this link
     * @param d new delay
     */
    public void setDelay(double d){
    	preProperties.setDelay(d);
    }
    
    /**
     * set bandwidth manager for this link
     * @param bm new bandwidth manager
     */
	public void setBandwidthManager(BandwidthManager bm){
		mBM=bm;
	}
	
	
	/**
	 * gets BandwidthManager
	 * 
	 * @return bandwidth manager
	 */
	 
	public BandwidthManager getBandwidthManager(){
		return mBM;
	}

    
}