nodehandleimpl.java

p2p仿真器。开发者可以工作在覆盖层中进行创造和测试逻辑算法或者创建和测试新的服务。PlanetSim还可以将仿真代码平稳转换为在Internet上的实验代码

package planet.generic.commonapi;

import planet.commonapi.NodeHandle;
import planet.commonapi.Id;

/**
 * NodeHandle for node. Being so simple his API, surely will be 
 * able to be reused for different nodes. It only mantain the Node Id
 * and a flag that informs if the related Node is alive.
 * 
 * @author <a href="mailto: [e-mail]">Jordi Pujol</a>
 * Date: 13/05/2004
 */
public class NodeHandleImpl extends NodeHandle implements Comparable {
	/**
	 * Node Id.
	 */
	private Id nodeId;
	/**
	 * true if related Node is alive.
	 */
	private boolean alive;
	
    public NodeHandleImpl()
    {
        nodeId = null;
        alive = false;
    }
    
	/**
	 * Gets the Id of the related node
	 * @see planet.commonapi.NodeHandle#getId()
	 * @return Id of the node
	 */
	public Id getId() {
		return nodeId;
	}

	/**
	 * Inform if the related node is alive.
	 * @see planet.commonapi.NodeHandle#isAlive()
	 * @return true if the related node is alive. false
	 * in other case.
	 */
	public boolean isAlive() {
		return alive;
	}
	
	/**
	 * Updates the alive flag.
	 * @see planet.commonapi.NodeHandle#setAlive(boolean)
	 * @param alive New value for the alive flag.
	 */
	public void setAlive(boolean alive) {
		this.alive = alive;
	}
	
	/**
	 * Returns the String representation of this NodeHandle
	 * @see java.lang.Object#toString()
	 * @return String representation with the nodeId and alive flag.
	 */
	public String toString() {
		//return "{NodeHandleImpl, nodeId=["+nodeId+"], alive=["+alive+"]}";
		return ""+nodeId;
	}
	
	/**
	 * Always returns one as proximity between any two nodes.
	 * @see planet.commonapi.NodeHandle#getProximity()
	 * @return Always one
	 */
	public int getProximity() {
		return 1;
	}
	
	/**
	 * Overwrites this method to reflect the comparison between
	 * the related Id's. That is:
	 * <br>
	 * <center><b>return getId().equals(((NodeHandle)obj).getId());</b></center>
	 * @see java.lang.Object#equals(java.lang.Object)
	 * @param obj NodeHandle to be compared.
	 * @return true if and only if the related Id's are equals. false in
	 * other case.
	 */
	public boolean equals(Object obj) {
		return getId().equals(((NodeHandle)obj).getId());
	}
	
    /**
     * Returns less than, equals than or greater than zero if this Id
     * is less than, equals than or greater than <b>obj</b> Id.
     * @param obj Another NodeHandle
     * @return Less than, equals than or greater than zero.
     * @see java.lang.Comparable#compareTo(java.lang.Object)
     */
    public int compareTo(Object obj) {
        return getId().compareTo(((NodeHandle)obj).getId());
    }
    
	/**
	 * Overwrites this method to reflect the hash code of the related Id.
	 * That is:
	 * <br>
	 * <center><b>return getId().hashCode();</b></center>
	 * @see java.lang.Object#hashCode()
	 * @return The hash code of the related Id.
	 */
	public int hashCode() {
		return getId().hashCode();
	}
    
    
    /**
     * Sets the 'newValue' Id and the flag alive to true.
     * @param newValue New Id.
     * @see planet.commonapi.NodeHandle#setValues(planet.commonapi.Id)
     */
    public NodeHandle setValues(Id newValue) {
        nodeId = newValue;
        alive = true;
        return this;
    }
    
    
    /**
     * Sets the values for this NodeHandle.
     * @param newValue The new Id
     * @param alive If the NodeHandle is alive
     * @see planet.commonapi.NodeHandle#setValues(planet.commonapi.Id, boolean)
     */
    public NodeHandle setValues(Id newValue, boolean alive) {
        nodeId = newValue;
        this.alive = alive;
        return this;
    }
}