java中根据对象的属性对ArrayList进行排序

Question

我希望按照电子邮件地址的顺序对我的对象进行排序。

这是我尝试过的方法，但它不起作用，但我什至不确定这是做我想做的事情的正确方法吗？

public static ArrayList<Billing> sortedListByEmail(ArrayList<Billing> Billing) {
    ArrayList<Billing> Sort = new ArrayList<Billing>();

    for (int i = 0; i < Sort.size(); i++) {
        Collections.sort(Sort, new Comparator<Billing>() {
            public int compare(Billing o1, Billing o2) {
                return o1.getEmail() > o2.getEmail() ? -1 : o1.getEmail().equals(o2.getEmail() ? 0 : 1);
            }
        });
    }

    return Sort;
}

其余班级：

import java.util.ArrayList;
import java.util.Collections;
import java.lang.Comparable;
import java.util.Comparator;

public class Billing extends User implements Comparable<User> {
    private Address billingAddress;
    private String email;

    public Billing(String id, String firstName, String lastName, String userName, String password, UserType userType, PermissionType permission, Boolean Status, Address billingAddress, String email) {
        super(id, firstName, lastName, userName, password, userType, permission, Status);

        this.billingAddress = billingAddress;
        this.email = email;
    }

    public Billing(String id, String firstName, String lastName, String userName, String password, UserType userType, PermissionType permission, Boolean Status, String email) {
        super(id, firstName, lastName, userName, password, userType, permission, Status);

    }

    public Billing(String id, String firstName, String lastName, String userName, String password, UserType userType, PermissionType permission, Boolean Status) {
        super(id, firstName, lastName, userName, password, userType, permission, Status);
    }

    public Address getBillingAddress() {
        return billingAddress;
    }

    public void setBillingAddress(Address billingAddress) {
        this.billingAddress = billingAddress;
    }

    public String getEmail() {
        return email;
    }

    public void setEmail(String email) {
        this.email = email;
    }
}

我如何完成按电子邮件地址顺序对对象进行排序？谢谢

Answer 1

尝试下面的代码：

billingList.sort(Comparator.comparing(a -> a.getEmail));