用java编写一个优先级调度算法PSA

好的，我可以为您解答这个问题。

首先，您需要了解什么是优先级调度算法PSA。PSA是Priority Scheduling Algorithm的缩写，即优先级调度算法。在这种算法中，每个进程都有一个优先级值，系统按照进程优先级的高低来选择下一个要执行的进程。若两个进程有相同的优先级，那么先到达的进程先执行。

接下来，我将为您提供一个用Java编写的PSA算法示例：

import java.util.*;

public class PrioritySchedulingAlgorithm {
    static Scanner sc = new Scanner(System.in);
    static int n, total_time, time_quantum;
    static int[] burst_time, arrival_time, priority, remaining_time;
    static float avg_waiting_time, avg_turnaround_time;

    public static void main(String[] args) {
        System.out.print("Enter the number of processes: ");
        n = sc.nextInt();

        burst_time = new int[n];
        arrival_time = new int[n];
        priority = new int[n];
        remaining_time = new int[n];

        for (int i = 0; i < n; i++) {
            System.out.println("Process " + (i + 1) + ":");
            System.out.print("Arrival Time: ");
            arrival_time[i] = sc.nextInt();
            System.out.print("Burst Time: ");
            burst_time[i] = sc.nextInt();
            System.out.print("Priority: ");
            priority[i] = sc.nextInt();
            remaining_time[i] = burst_time[i];
            total_time += burst_time[i];
        }

        System.out.print("Enter the time quantum: ");
        time_quantum = sc.nextInt();

        // Sort the processes by arrival time
        for (int i = 0; i < n - 1; i++) {
            for (int j = i + 1; j < n; j++) {
                if (arrival_time[i] > arrival_time[j]) {
                    int temp = arrival_time[i];
                    arrival_time[i] = arrival_time[j];
                    arrival_time[j] = temp;

                    temp = burst_time[i];
                    burst_time[i] = burst_time[j];
                    burst_time[j] = temp;

                    temp = priority[i];
                    priority[i] = priority[j];
                    priority[j] = temp;

                    temp = remaining_time[i];
                    remaining_time[i] = remaining_time[j];
                    remaining_time[j] = temp;
                }
            }
        }

        int current_time = 0;
        int[] waiting_time = new int[n];
        int[] turnaround_time = new int[n];
        boolean[] is_completed = new boolean[n];

        while (current_time < total_time) {
            int highest_priority_index = -1;
            int highest_priority = Integer.MAX_VALUE;

            for (int i = 0; i < n; i++) {
                if (arrival_time[i] <= current_time && !is_completed[i] && priority[i] < highest_priority) {
                    highest_priority = priority[i];
                    highest_priority_index = i;
                }
            }

            if (highest_priority_index == -1) {
                current_time++;
                continue;
            }

            if (remaining_time[highest_priority_index] <= time_quantum) {
                current_time += remaining_time[highest_priority_index];
                turnaround_time[highest_priority_index] = current_time - arrival_time[highest_priority_index];
                waiting_time[highest_priority_index] = turnaround_time[highest_priority_index] - burst_time[highest_priority_index];
                remaining_time[highest_priority_index] = 0;
                is_completed[highest_priority_index] = true;
            } else {
                current_time += time_quantum;
                remaining_time[highest_priority_index] -= time_quantum;
            }
        }

        for (int i = 0; i < n; i++) {
            avg_waiting_time += waiting_time[i];
            avg_turnaround_time += turnaround_time[i];
        }

        avg_waiting_time /= n;
        avg_turnaround_time /= n;

        System.out.println("\nAvg Waiting Time: " + avg_waiting_time);
        System.out.println("Avg Turnaround Time: " + avg_turnaround_time);
    }
}

希望这个示例能对您有所帮助！