CPU进程调度简单模拟(Round Robin)--Java

这是我的作业，要求的输出结果是：各进程的等待时间、周转时间及平均等待、周转时间
个人觉得比较复杂的地方是要考虑进程完成运行时的不同情况：用了多少次时间片、完成运行时时间片有无剩余等，这些都对计算有影响。我用的是分情况考虑来计算的方法，虽然最终能得出结果，但感觉有点繁琐。希望各位大神如果有更简洁的方法，可以指导一下~~~

Work Class：

/* * Student name: Xin * Program name: Work * Program purpose: Test the scheduling algorithm simulation (Round Robin) */import java.util.*;public class Work {// 变量private int arrivalTime;private int burstTime;private String name;// 平均等待、周转时间private int turnAroundTime;private int waitingTime;// 进程还需要时间（运行时间-已使用时间）private int restRequireTime;// 进程已使用时间private int usedTime;// 获取变量值public int getArrivalTime() {return arrivalTime;}public int getBurstTime() {return burstTime;}public String getName() {return name;}public int getWaitingTime() {return waitingTime;}public int getTurnAroundTime() {return turnAroundTime;}public int getRestRequireTime() {return restRequireTime;}public int getUsedTime() {return usedTime;}// 设置变量值public void setArrivalTime(int arrivalTime) {this.arrivalTime = arrivalTime;}public void setBurstTime(int burstTime) {this.burstTime = burstTime;}public void setName(String name) {this.name = name;}public void setWaitingTime(int waitingTime) {this.waitingTime = waitingTime;}public void setTurnAroundTime(int turnAroundTime) {this.turnAroundTime = turnAroundTime;}public void setRestRequireTime(int restRequireTime) {this.restRequireTime = restRequireTime;}public void setUsedTime(int usedTime) {this.usedTime = usedTime;}// 第一组数据（进程同时到达）public static Queue<Work> generateProcess1(){String[] name1 = {"A","B","C","D","E"};int[] at1 = {0,0,0,0,0};int[] bt1 = {7,3,9,5,1};Queue<Work> runQueue1= new LinkedList<>();for(int i = 0; i<5;i++){    Work process = new Work();    process.setName(name1[i]);    process.setArrivalTime(at1[i]);    process.setBurstTime(bt1[i]);    runQueue1.add(process);}return runQueue1;}// 第二组数据（到达时间不同）public static Queue<Work> generateProcess2(){String[] name2 = {"A","B","C","D","E"};int[] at2 = {0,2,4,6,8};int[] bt2 = {7,3,9,5,1};Queue<Work> runQueue2= new LinkedList<>();for(int i = 0; i<5;i++){    Work process = new Work();    process.setName(name2[i]);    process.setArrivalTime(at2[i]);    process.setBurstTime(bt2[i]);    runQueue2.add(process);}return runQueue2;}}

Test Class:

/* * Student name: Xin * Program name: Test * Program purpose: Test the scheduling algorithm sumulation (Round Robin) */import java.util.*;/* * 思路：因为每个进程轮流运行，所以不需事先对进程进行排序（不像SJF和PriorityFirst）。因为有不同的队列，当要选择下一个运行的程序，需要考虑一下情况：（1）准备队列为空；（2）等待队列为空，但原始队列不为空（即有程序很晚才到，别的程序都运行完了它才到达）；（3）等待队列不为空*/public class Test  {public static int numberOfProcess;public static int timeQuantum;// Main methodpublic static void main(String[] args) {    // 创建Queue    Queue<Work> q1 = new LinkedList<>();    Queue<Work> q2 = new LinkedList<>();    // Call the generateProcess method     q1 = Work.generateProcess1();    q2 = Work.generateProcess2();System.out.println("--------------------------------------------------");    System.out.println("The running order and details of data set 1: "); System.out.println("--------------------------------------------------");    roundRobin(q1);System.out.println("--------------------------------------------------");    System.out.println("The running order and details of data set 2: ");System.out.println("--------------------------------------------------");    roundRobin(q2);}public static Queue<Work> roundRobin(Queue<Work> queue) {    // 设置变量    double averageWaitTime = 0.00;    double averageTurnAroundTime = 0.00;    int startTime = 0;    int finishTime = 0;    int queueSize = queue.size();    Work process;    // 用户输入时间片大小    Scanner userInputTime = new Scanner(System.in);    System.out.println("Enter the time Quantum");    timeQuantum = userInputTime.nextInt();    // 创建准备队列，等待队列    Queue<Work> waitQueue = new LinkedList<>();         Queue<Work> readyQueue = new LinkedList<>();    // 当所有队列都不为空    while(!queue.isEmpty() || !readyQueue.isEmpty() || !waitQueue.isEmpty()){    // 如果原始队列不为空，且第一个进程的到达时间小于准备队列里的进程的结束时间（即意味着当准备队列里的进程完成运行，下一个进程已经到达），则可以将队列里的进程加入到准备队列里    while(queue.peek()!=null && queue.peek().getArrivalTime()<=finishTime)            readyQueue.add(queue.poll());    // 如果准备队列不为空，则运行准备队列里的进程    if (!readyQueue.isEmpty())    process = readyQueue.poll();    // 如果等待队列为空，而原始队列不为空，则运行原始队列中的进程    else if( !queue.isEmpty() && waitQueue.isEmpty())      process = queue.poll();     else     // If the waitQueue is not empty, run the process in waitQueue    process = waitQueue.poll();    // 计算开始时间和结束时间    startTime = Math.max(process.getArrivalTime(),finishTime);    finishTime = startTime + timeQuantum;     // 计算进程已使用时间和剩余需要时间    process.setUsedTime(process.getUsedTime()+timeQuantum);    process.setRestRequireTime(process.getBurstTime()-process.getUsedTime());    // 如果进程用完时间片仍未完成运行，则返回等待队列    if(process.getRestRequireTime()>0)    {    waitQueue.add(process);}    // If the process finished processing    else    {    // 计算等待时间和总等待时间    // Consider two situations: (1)the process has remain time when it finished; (2)No remain time    if(process.getRestRequireTime()>0)    {        process.setTurnAroundTime(finishTime-process.getArrivalTime());}    else     {    // 如果进程没有用完时间片，则重新计算结束时间    process.setTurnAroundTime(finishTime-process.getArrivalTime()+process.getRestRequireTime());    finishTime = finishTime+process.getRestRequireTime();}    averageTurnAroundTime += process.getTurnAroundTime();    // 计算等待时间，周转时间    // 有两种情况：    // (1)进程只用了一时间片    // (2)进程用了不止一个时间片    if(process.getUsedTime()>timeQuantum)    {    process.setWaitingTime(startTime-process.getUsedTime()+timeQuantum - process.getArrivalTime());}    else     {    process.setWaitingTime(startTime-process.getArrivalTime());}    averageWaitTime += process.getWaitingTime();    // 输出计算结果    System.out.println("\n"+process.getName()+" process finishes processing now. Details are shown: ");    System.out.println("Total waiting time: "+ process.getWaitingTime());    System.out.println("Total turn around time: "+process.getTurnAroundTime());}}// 计算平均值averageTurnAroundTime /= queueSize;averageWaitTime /= queueSize;// Print out the avgsSystem.out.println("\nAverage Wait time: "+ averageWaitTime);System.out.println("Average Turn Around time: "+ averageTurnAroundTime);return readyQueue;  }}

运行结果：