Java如何在值更新时维护数组列表中扫描对象的顺序

Question

我有一个包含患者姓名和紧急级别的类，该类实现了类似的功能:

class Patient implements Comparable<Patient>{
    private String name;
    private int emergencyLvl;

    public Patient(String name, int emergencyLvl)
    {
        this.name = name;
        this.emergencyLvl = emergencyLvl;

    }

    public String getName(){
        return this.name;

    }
    public int getEmergencyLvl(){
        return this.emergencyLvl;

    }
    public  void  setEmergencyLvl(int updateLvl){
        this.emergencyLvl = updateLvl;

    }
    public void setName(String newName){
        this.name = newName;

    }
    public int compareTo(Patient p){

        int compareEmergency = ((Patient) p).getEmergencyLvl();

        return compareEmergency - this.emergencyLvl;

    **//I believe my error comes from here**




        }
}

**可以说这是我的输入文件:

3
0 david 30
0 may 60
1 david 30
2

*3 = 查询数量，0 = 要添加到数组列表中的新患者，1 = 更新紧急级别(示例 30 + 30 = 60)。 2 = 按降序打印紧急级别和名称。**

但是，我的程序设法正确扫描新患者并将其添加到数组列表中，但每当需要更新紧急级别时，顺序都是错误的。

例如，在大卫紧急级别更新之前。顺序是(5月60日，大卫30)但更新大卫紧急级别后，由于大卫先到达，因此正确的顺序应该是(大卫 60，5 月 60)。

不幸的是，我未能正确更新序列。这是我的主程序:

更新紧急级别:

void UpdateEmergencyLvl(String patientName, int incEmergencyLvl) {

        for(Patient p: a1){
            if(p.getName().equals(patientName)){
                int newEmergencyLvl = p.getEmergencyLvl() +
                incEmergencyLvl;
                p.setEmergencyLvl(newEmergencyLvl);

                }

            }

            Collections.sort(a1);

    }

Answer 1

首先，您需要为 Patient 类添加一个新属性，您的新公共(public) Patient 应如下所示:

public Patient(String name, int emergencyLvl, int patIndx)
        {
            this.name = name;
            this.emergencyLvl = emergencyLvl;
            this.patIndx = patIndx;

        }

完成此操作后，为索引创建一个 getter；在您的阅读方法中，您可以只向该索引添加一个 int 。对于比较方法，由于到达索引比共享相同的 EmergencyLvl 更重要，我会这样做:

public int compareTo(Patient p){

        int compareEmergency = ((Patient) p).getEmergencyLvl();

        int aux= compareEmergency - this.emergencyLvl;

        int compareIndex= ((Patient) p).getIndex();
        if(compareIndex>this.patIndx) aux=compareIndex-this.patIndx;
        return aux;    



        }

使用的扫描仪:

 void run() throws Exception {


    BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
    PrintWriter pr = new PrintWriter(new BufferedWriter(new OutputStreamWriter(System.out)));
    int numCMD = Integer.parseInt(br.readLine()); // note that numCMD is >= N
    int index=0;//starting index at 0
    while (numCMD-- > 0) {
      StringTokenizer st = new StringTokenizer(br.readLine());
      index++;
      int command = Integer.parseInt(st.nextToken());
      switch (command) {
        case 0: ArriveAtHospital(st.nextToken(), Integer.parseInt(st.nextToken())); 
               // you will need a index setter for this, assuming this is the moment when you add the patient to the patient list:
               ArriveAtHospìtalOrder(index);//as I cant see how the method ArriveAtHospital works, I showed you a possible method that takes the index.
               break;
        case 1: UpdateEmergencyLvl(st.nextToken(), Integer.parseInt(st.nextToken())); break;

        case 3: pr.println(Query()); break;
      }


    }
    pr.close();

这是一种可能的方法，ArriveAtHospitalIndex 只是为了说明，因为我不知道如何将参数传递给 ArriveAtHospital 方法，这只是为了让您知道何时应该传递索引。您对台词有一点评论。