How to sort a list using comparator in Descending order (based on salary which is a long value)

Question

How to sort a list using comparator in Descending order (based on salary which is a long value)

---

class Empl{

    private String name;
    private long salary;

    public Empl(String n, long s){
        this.name = n;
        this.salary = s;
    }

    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
    public long getSalary() {
        return salary;
    }
    public void setSalary(long salary) {
        this.salary = salary;
    }

}

Answer 1

If you are using Java 8 you can use Stream#sorted with Comparator#comparingLong like this :

list = list.stream()
        .sorted(Comparator.comparingLong(Empl::getSalary).reversed())
        .collect(toList());

Note the .reversed() when you use it the list is sorted descendant, else if you don't use it, it is sorted ascendant.

Answer 2

Try this:

Descending

Collections.sort(modelList, new Comparator<Empl>() {
        @Override
        public int compare(Empl o1, Empl o2) {
            return o2.getSalary().compareTo(o1.getSalary());
        }
});

Ascending

Collections.sort(modelList, new Comparator<Empl>() {
            @Override
            public int compare(Empl o1, Empl o2) {
                return o1.getSalary().compareTo(o2.getSalary());
            }
});

Answer 3

Use this way

Collections.sort(employeeList, new Comparator<VariationsItem>() {
    @Override
    public int compare(Empl lhs, Empl rhs) {
        return ((Long) rhs.getSalary()).compareTo((Long) lhs.getSalary());
    }
});

Answer 4

如果您使用的是Java-8，则可以直接在列表上调用默认的sort方法，以提供必要的比较器。

list.sort(Comparator.comparingLong(Empl::getSalary).reversed());