timerqueue.java

来自「DSr project for the java applications」· Java 代码 · 共 55 行

package dsr;


import java.io.*;
import java.util.*;
import java.net.*;

//this implements the queue of timed events.
public class TimerQueue {
  static Vector timerQueue;      //vector of entries
  //constructor
  TimerQueue() {
    timerQueue = new Vector(3,2);
  }

  //prints out the Timer queue entry
  public static void PrintTimerQueue(){
    Iterator r = timerQueue.iterator();
    System.out.println("************************************************************************");
    System.out.println("The entries in the timer queue are");
    System.out.println("************************************************************************");
    while (r.hasNext()) {
      System.out.println(((TimerQueueEntry)r.next()).toString());
    }
    System.out.println("************************************************************************");
  }

  //insert the timer entry in the queue
  public static void insertInTimerQueue(long t, InetAddress s, InetAddress d, short r, short f) {
    TimerQueueEntry tmp = new TimerQueueEntry(t, s, d, r, f);
    timerQueue.addElement(tmp);
  }

  //checks to see if the RREQ packet is still valid in the timer queue. this is stop duplicate
  //RREQ request flowing in the network. returns true if and only if a new RREQ needs to be generated
  public static boolean checkForThisRREQInTimerQueue(InetAddress src, InetAddress dst, short f) {
    TimerQueueEntry tmp = new TimerQueueEntry();
    Iterator t = timerQueue.iterator();
    long currTime = System.currentTimeMillis();
    while (t.hasNext()) {
      tmp = (TimerQueueEntry)t.next();
      if (tmp.flags == f && tmp.destIP.equals(dst) && tmp.srcIP.equals(src)
          && currTime > tmp.validTime) {
        if (tmp.retries <= 0)
          return true;
        else {
          tmp.retries--;
          return false;
        }
      }
    }
    return false;
  }
}