比较具有多个涉及布尔值的属性的列表 [英] compare list with multiple attributes involving a boolean

问题描述

我有一些类实现比较器接口，以通过添加患者对象对ArrayList进行排序，我想按多个属性对列表进行排序，而仅对Enums进行排序没有问题，但是我想通过对a进行排序来覆盖此排序布尔值.我知道我不能使用compareTo方法，因为它不是Wrapper类，但是我找不到通过boolean对列表进行排序的合适方法.

I have some classes that implement the comparator interface to sort an ArrayList by adding patient objects, I want to sort the list by multiple attributes and have no problem sorting with just Enums, however I want to override this sort by sorting with a boolean. I know I cannot use the compareTo method as it is not a Wrapper class but I am not able to find a suitable way to sort the list via boolean.

任何帮助将不胜感激.

    public Patient(int nhsNumber, String name, Status triage, boolean previouslyInQueue, boolean waitingTime){
    this.nhsNumber = nhsNumber;
    this.name = name;
    this.triage = triage;
    this.previouslyInQueue = previouslyInQueue;
    this.waitingTime = waitingTime;

}

这是我的比较器类

public class PatientInQueueComparator implements Comparator<Patient> {

@Override
public int compare(Patient p1, Patient p2) {

    if(p1.isPreviouslyInQueue() && !p2.isPreviouslyInQueue()){
        return 1;
        }else if(p1.isPreviouslyInQueue() && p2.isPreviouslyInQueue()){
        return -1;
        }
        return 0;
}

我的主要方法

List<Patient> queue = new ArrayList<Patient>();

queue.add(new Patient(1, "Bob", Status.URGENT, true, false)); //1st
queue.add(new Patient(2, "John", Status.EMERGENCY, false, false)); //5th
queue.add(new Patient(3, "Mary", Status.NON_URGENT, false, false)); //6th
queue.add(new Patient(4, "Luke", Status.SEMI_URGENT, false, true)); //4th
queue.add(new Patient(5, "Harry", Status.NON_URGENT, true, false)); //2nd
queue.add(new Patient(6, "Mark", Status.URGENT, false, true)); //3rd


System.out.println("*** Before sorting:");

for (Patient p1 : queue) {
    System.out.println(p1);
}

Collections.sort(queue, new PatientComparator( 
        new PatientInQueueComparator(),
        new PatientTriageComparator())
);

System.out.println("\n\n*** After sorting:");

for (Patient p1 : queue) {
    System.out.println(p1);
}

患者比较器

    private List<Comparator<Patient>> listComparators;

 @SafeVarargs
    public PatientComparator(Comparator<Patient>... comparators) {
        this.listComparators = Arrays.asList(comparators);
    }

@Override
public int compare(Patient p1, Patient p2) {
    for (Comparator<Patient> comparator : listComparators) {
        int result = comparator.compare(p1, p2);
        if (result != 0) {
            return result;
        }
    }
    return 0;
}

推荐答案

如果希望true的值大于false，则必须更正 您的compare()方法:

If you want true values to be greater than false, you must correct your compare() method:

@Override
public int compare(Patient p1, Patient p2) {

    if (p1.isPreviouslyInQueue() && !p2.isPreviouslyInQueue()) 
        return -1;
    if (!p1.isPreviouslyInQueue() && p2.isPreviouslyInQueue()) 
        return 1;
    return 0;
}

注意第二个if.另一个实现可能是:

notice to second if. another implementation may be :

@Override
public int compare(Patient p1, Patient p2) {
    return ((Boolean)p2.isPreviouslyInQueue()).compareTo(p1.isPreviouslyInQueue());
}

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