1、案例：
Person对象（名字，id,年龄）
要求按照，年龄从小到大排序，年龄相等，按照名字的字典顺序de倒序排序
2、案例设计：
1）使用ArrayList存储Person对象，
2）利用Collections.sort()进行排序
3）输出结果
3、代码分享：
package CollectionDemo;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import java.util.Comparator;
class Person{
private int id;
private int age;
private String name;
public Person(int id, int age,String name){
this.id=id;
this.age=age;
this.name=name;
}
public void setId(int id) {
this.id = id;
}
public void setAge(int age) {
this.age = age;
}
public void setName(String name){
this.name=name;
}
public int getId() {
return id;
}
public int getAge() {
return age;
}
public String getName() {
return name;
}
@Override
public String toString() {
return "Person{" +
"id=" + id +
", age=" + age +
", name='" + name + '\'' +
'}';
}
}
public class CollectionDemo2 {
public static void main(String[] args){
List<Person> arrayList =new ArrayList<>();
arrayList.add(new Person(001,20,"yang"));
arrayList.add(new Person(002,20,"zhang"));
arrayList.add(new Person(003,30,"li"));
arrayList.add(new Person(004,40,"Coco"));
arrayList.add(new Person(005,40,"Marry"));
Collections.sort(arrayList,new Comparator<Person>(){
public int compare(Person o1,Person o2){
if(o1.getAge()!=o2.getAge()){
return o1.getAge()-o2.getAge();//按照年龄升序排序
}else{
return o2.getName().compareToIgnoreCase(o1.getName());//按照名字的字典顺序倒序排序
}
}
});
//输出
for(Person p:arrayList){
System.out.println(p);
}
}
}
输出：
Person{id=2, age=20, name='zhang'}
Person{id=1, age=20, name='yang'}
Person{id=3, age=30, name='li'}
Person{id=5, age=40, name='Marry'}
Person{id=4, age=40, name='Coco'}
