定义进程工作对象

class Job {
    String name;
     //到达时间
    int arrivalTime;
    //执行时间
    int executionTime;

    public Job(String name, int arrivalTime, int executionTime) {
        this.name = name;
        this.arrivalTime = arrivalTime;
        this.executionTime = executionTime;
    }
}

测试方法

    public static void fcfs_run() {
        // 创建作业列表
        List<Job> jobs = new ArrayList<>();
        jobs.add(new Job("Job1", 3, 10));
        jobs.add(new Job("Job2", 2, 10));
        jobs.add(new Job("Job3", 1, 10));
        // 按照到达时间进行排序
        jobs.sort(Comparator.comparingInt(j -> j.arrivalTime));
        // 周转时间=完成时间-到达时间;
        int finishTotal = 0;
        int turnaroundTimeTotal = 0;
        for (Job job : jobs) {
            //完成
            finishTotal += job.arrivalTime + job.executionTime;
            // 计算周转时间
            int turnaroundTime = finishTotal - job.arrivalTime;
            // 更新周转时间总和
            turnaroundTimeTotal += turnaroundTime;
            System.out.println("作业 " + job.name + " 周转时间：" + turnaroundTime);
        }
        double averageTurnaroundTime = (double) turnaroundTimeTotal / jobs.size();
        BigDecimal bd = new BigDecimal(averageTurnaroundTime);
//        四舍五入
        BigDecimal roundedNumber = bd.setScale(2, RoundingMode.HALF_UP);
        System.out.println("平均周转时间：" + roundedNumber.doubleValue());
    }

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