代码Java通过选择来实现时间片轮转调度、优先数调度、最短进程优先、最短剩余时间优先四种调度方法

以下是Java代码实现四种调度方法：

1. 时间片轮转调度：

import java.util.LinkedList;
import java.util.Queue;

public class TimeSliceSchedule {
    public static void main(String[] args) {
        int[] processTime = {10, 5, 8, 12};
        int timeSlice = 5;
        int totalTime = 0;

        Queue<Integer> queue = new LinkedList<>();
        for (int i = 0; i < processTime.length; i++) {
            queue.offer(processTime[i]);
            totalTime += processTime[i];
        }

        System.out.println("时间片轮转调度算法：");
        System.out.println("进程执行顺序如下：");
        while (!queue.isEmpty()) {
            int time = Math.min(queue.peek(), timeSlice);
            totalTime -= time;
            System.out.print("P" + (processTime.length - queue.size() + 1) + " ");
            queue.poll();
            if (totalTime > 0) {
                queue.offer(time);
            }
        }
    }
}

2. 优先数调度：

import java.util.ArrayList;
import java.util.Collections;
import java.util.Comparator;
import java.util.List;

public class PrioritySchedule {
    public static void main(String[] args) {
        int[] processTime = {10, 5, 8, 12};
        int[] priority = {2, 3, 1, 4};

        List<Process> list = new ArrayList<>();
        for (int i = 0; i < processTime.length; i++) {
            list.add(new Process(i + 1, processTime[i], priority[i]));
        }

        System.out.println("优先数调度算法：");
        System.out.println("进程执行顺序如下：");
        Collections.sort(list, new Comparator<Process>() {
            @Override
            public int compare(Process p1, Process p2) {
                return p2.priority - p1.priority;
            }
        });

        for (Process p : list) {
            System.out.print("P" + p.id + " ");
        }
    }

    static class Process {
        int id;
        int time;
        int priority;

        public Process(int id, int time, int priority) {
            this.id = id;
            this.time = time;
            this.priority = priority;
        }
    }
}

3. 最短进程优先：

import java.util.ArrayList;
import java.util.Collections;
import java.util.Comparator;
import java.util.List;

public class ShortestJobFirstSchedule {
    public static void main(String[] args) {
        int[] processTime = {10, 5, 8, 12};

        List<Process> list = new ArrayList<>();
        for (int i = 0; i < processTime.length; i++) {
            list.add(new Process(i + 1, processTime[i]));
        }

        System.out.println("最短进程优先调度算法：");
        System.out.println("进程执行顺序如下：");
        Collections.sort(list, new Comparator<Process>() {
            @Override
            public int compare(Process p1, Process p2) {
                return p1.time - p2.time;
            }
        });

        for (Process p : list) {
            System.out.print("P" + p.id + " ");
        }
    }

    static class Process {
        int id;
        int time;

        public Process(int id, int time) {
            this.id = id;
            this.time = time;
        }
    }
}

4. 最短剩余时间优先：

import java.util.ArrayList;
import java.util.Collections;
import java.util.Comparator;
import java.util.List;

public class ShortestRemainingTimeFirstSchedule {
    public static void main(String[] args) {
        int[] processTime = {10, 5, 8, 12};
        int currentTime = 0;

        List<Process> list = new ArrayList<>();
        for (int i = 0; i < processTime.length; i++) {
            list.add(new Process(i + 1, processTime[i]));
        }

        System.out.println("最短剩余时间优先调度算法：");
        System.out.println("进程执行顺序如下：");
        while (!list.isEmpty()) {
            Collections.sort(list, new Comparator<Process>() {
                @Override
                public int compare(Process p1, Process p2) {
                    return p1.time - p2.time;
                }
            });

            for (int i = 0; i < list.size(); i++) {
                Process p = list.get(i);
                if (p.time <= currentTime) {
                    System.out.print("P" + p.id + " ");
                    list.remove(i);
                    currentTime += p.time;
                    break;
                }
            }
        }
    }

    static class Process {
        int id;
        int time;

        public Process(int id, int time) {
            this.id = id;
            this.time = time;
        }
    }
}