tfprocessschedule.java~45~

进程调度和存储管理模拟

package cn.edu.cauc.crab.ossimulate;

import java.util.*;
import javax.swing.*;

/**
 * <p>Title: OS simulate</p>
 * <p>Description: This is my home work.</p>
 * <p>Copyright: Copyleft (c) 2004</p>
 * <p>Company: CAUC</p>
 * @author Crab
 * @version 0.1
 */

/**
 * To simulate time fragment scheduling.
 *
 * @author Crab
 * @version 0.1
 * @see cn.edu.cauc.crab.ossimulate.ProcessSchdule
 */
public class TFProcessSchedule extends ProcessSchedule {

    JTextArea out;
    private int timeFragment;

    /**
     * extend from ProcessSchdule a List PCBs.
     * @param timeFragment the time fragment to schedule the process.
     */
    public TFProcessSchedule(int timeFragment) {
        super();
        this.timeFragment = timeFragment;
    }

    public TFProcessSchedule(int timeFragment, JTextArea out) {
        super();
        this.timeFragment = timeFragment;
        this.out = out;
    }
    /**
     * extends from ProcessSchedule
     * After addProcess() is calling,
     * use to start scheduling.
     */
    public void start() {
        int time = 0;

        while (!PCBs.isEmpty()) {
            Iterator p = PCBs.iterator();
            while (p.hasNext()) {
                PCB tempPCB = (PCB)p.next();
                if (tempPCB.arriveTime <= time && tempPCB.leftTime != 0) {
                    if (tempPCB.leftTime == tempPCB.serveTime) {
                        tempPCB.beginTime = time;
                    }
                    if (tempPCB.leftTime >= timeFragment) {
                        tempPCB.leftTime -= timeFragment;
                        time += timeFragment;
                        if (tempPCB.leftTime == 0) {
                            tempPCB.finishTime = time;
                        }
                    } else {
                        time += tempPCB.leftTime;
                        tempPCB.finishTime = time;
                        tempPCB.leftTime = 0;
                    }
                    if (tempPCB.leftTime == 0) {
                        tempPCB.rollTime = tempPCB.finishTime - tempPCB.arriveTime;
                            // use tr ts to rise the precesion.
                            float tr = tempPCB.rollTime;
                            float ts = tempPCB.serveTime;
                            tempPCB.nullWorkRate =  tr / ts;

                            if (out == null) {
                                System.out.println("PID: " + tempPCB.pid
                                        +" Arrive: " + tempPCB.arriveTime
                                        + " Serve: " + tempPCB.serveTime
                                        + " Begin: " + tempPCB.beginTime
                                        + " Finish: " + tempPCB.finishTime
                                        + " Roll: " + tempPCB.rollTime
                                        + " nullWorkRate: " + tempPCB.nullWorkRate);
                            } else {
                                out.append("PID: " + tempPCB.pid
                                        +" Arrive: " + tempPCB.arriveTime
                                        + " Serve: " + tempPCB.serveTime
                                        + " Begin: " + tempPCB.beginTime
                                        + " Finish: " + tempPCB.finishTime
                                        + " Roll: " + tempPCB.rollTime
                                        + " nullWorkRate: " + tempPCB.nullWorkRate
                                        + "\n");
                            }
                            p.remove();//remove the finish process.
                    } else {
                        if (out == null) {
                            System.out.println("@PID: " + tempPCB.pid
                                    + " LeftTime: " + tempPCB.leftTime);
                        } else {
                            out.append("@PID: " + tempPCB.pid
                                    + " LeftTime: " + tempPCB.leftTime
                                    + "\n");
                        }
                    }
                } else {
                    time ++;
                }
            }
        }
    }

    public static void main(String[] args) {
        ProcessSchedule pSch = new TFProcessSchedule(3);
        //pSch.addProcess(new Process(10), 0);
        pSch.addProcess(new Process(10), 1);
        pSch.addProcess(new Process(10), 2);
        pSch.addProcess(new Process(10), 3);
        pSch.addProcess(new Process(10), 4);
        pSch.start();
    }
}