如题,闲话少说直接上代码!
public class Solution0604 {
public static void main(String[] args) {
List<Student> studentList = new LinkedList<>();
Student student1 = new Student();
Student student2 = new Student();
student1.setCode("2021060401");
student1.setName("小明");
student1.setAge(20);
student2.setCode("2021060402");
student2.setName("小红");
student2.setAge(19);
studentList.add(student1);
studentList.add(student2);
System.out.println("原集合");
studentList.forEach(e -> {
System.out.println(e.toString());
});
//对单字段排序,对age排序
List<Student> list = studentList.stream().sorted(Comparator.comparing(Student::getAge)).collect(Collectors.toList());
System.out.println("对单字段排序");
list.forEach(e -> {
System.out.println(e.toString());
});
// 对双字段排序,code和age
Comparator<Student> byCode = Comparator.comparing(Student::getCode);
Comparator<Student> byAge = Comparator.comparing(Student::getAge);
studentList.sort(byAge.thenComparing(byCode));
System.out.println("先按年龄排序后集合");
studentList.forEach(e -> {
System.out.println(e.toString());
});
System.out.println("对上结果先按学号排序后集合");
studentList.sort(byCode.thenComparing(byAge));
studentList.forEach(e -> {
System.out.println(e.toString());
});
}
}
class Student {
private String code;
private String name;
private Integer age;
public String getCode() {
return code;
}
public void setCode(String code) {
this.code = code;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public Integer getAge() {
return age;
}
public void setAge(Integer age) {
this.age = age;
}
@Override
public String toString() {
return "Student{" +
"code='" + code + '\'' +
", name='" + name + '\'' +
", age=" + age +
'}';
}
}
打印结果:
原集合
Student{code='2021060401', name='小明', age=20}
Student{code='2021060402', name='小红', age=19}
对单字段排序
Student{code='2021060402', name='小红', age=19}
Student{code='2021060401', name='小明', age=20}
先按年龄排序后集合
Student{code='2021060402', name='小红', age=19}
Student{code='2021060401', name='小明', age=20}
对上结果先按学号排序后集合
Student{code='2021060401', name='小明', age=20}
Student{code='2021060402', name='小红', age=19}