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对ArrayList集合中的元素进行排序

article 2025/8/27 9:36:52

如果要对ArrayList集合中的元素进行排序，需要用到java工具包中的Collections类的sort方法。

具体用法可以查看jdk帮助文档。

在这里先创建一个Person类，包含姓名，性别，年龄，身份证号，出生日期。如以下代码：

public class Person {private String name;private String birthday;private String idCard;private char sex;private int age;//getters和setterspublic String getName() {return name;}public void setName(String name) {this.name = name;}public String getBirthday() {return birthday;}public void setBirthday(String birthday) {this.birthday = birthday;}public String getIdCard() {return idCard;}public void setIdCard(String idCard) {this.idCard = idCard;}public char getSex() {return sex;}public void setSex(char sex) {this.sex = sex;}public int getAge() {return age;}public void setAge(int age) {this.age = age;}//构造函数public Person(){}public Person(String name,String birthday,String idCard,char sex,int age){this.name = name;this.birthday = birthday;this.idCard = idCard;this.sex = sex;this.age = age;}//输出信息public String toString(){return name+","+sex+","+age+","+birthday+","+idCard;}
}

然后创建排序的类（其中包括按照姓名排序，按照年龄排序，按照出生日期排序），如以下代码所示：

import java.util.Comparator;
public class CompareName implements Comparator<Person>{//按照姓名进行排序@Overridepublic int compare(Person p1, Person p2) {// TODO Auto-generated method stubreturn p1.getName().compareTo(p2.getName());}
}

class CompareBirthday implements Comparator<Person>{//按照出生日期进行排序@Overridepublic int compare(Person p1, Person p2) {// TODO Auto-generated method stubreturn p1.getBirthday().compareTo(p2.getBirthday());}
}

class CompareAge implements Comparator<Person>{//按照年龄进行排序@Overridepublic int compare(Person p1, Person p2) {// TODO Auto-generated method stubif(p1.getAge()>p2.getAge())return 1;else return -1;}
}

最后创建一个主类（在这里我明明为First），用来调用以上所写的类并使程序可以执行。

import java.util.ArrayList;
import java.util.Collections;
public class First {public static void main(String[] args){ArrayList<Person> value = new ArrayList<Person>();Person p1 = new Person("张三","1994-3-3","45612346548",'男',26);Person p2 = new Person("赵四","2000-5-24","16546165746",'男',20);Person p3 = new Person("刘武","1997-2-3","156461656487",'男',23);Person p4 = new Person("丁晓晓","1996-6-13","36548588788",'女',24);//将创建的各元素添加到ArrayList集合中value.add(p1);value.add(p2);value.add(p3);value.add(p4);CompareName cn = new CompareName();CompareBirthday cb = new CompareBirthday();CompareAge ca = new CompareAge();System.out.println("\n按姓名排序：");//其中\n表示换行Collections.sort(value,cn);for(int i = 0; i < value.size(); i++)System.out.println(value.get(i).toString());System.out.println("\n按年龄排序：");Collections.sort(value,ca);for(int i = 0; i < value.size(); i++)System.out.println(value.get(i).toString());System.out.println("\n按生日排序：");Collections.sort(value,cb);for(int i = 0; i < value.size(); i++)System.out.println(value.get(i).toString());}
}