diff --git a/javaSE-day07/src/com/inmind/lambda01/Demo02.java b/javaSE-day07/src/com/inmind/lambda01/Demo02.java new file mode 100644 index 0000000..eeba643 --- /dev/null +++ b/javaSE-day07/src/com/inmind/lambda01/Demo02.java @@ -0,0 +1,34 @@ +package com.inmind.lambda01; + +import java.util.ArrayList; +import java.util.Collections; +import java.util.Comparator; + +/* +学习的内容:使用Lambda表达式简化有参数有返回值的方法(比较器) + +使用比较器,对学生对象按成绩降序排序 + */ +public class Demo02 { + public static void main(String[] args) { + ArrayList students = new ArrayList<>(); + students.add(new Student("张三1", 95)); + students.add(new Student("张三2", 90)); + students.add(new Student("张三3", 98)); + + /*Collections.sort(students, new Comparator() { + *//* + 我-它:升序 + 它-我:降序 + *//* + @Override + public int compare(Student o1, Student o2) { + return o2.score - o1.score; + } + });*/ + + Collections.sort(students,(Student o1, Student o2)->{ return o2.score - o1.score;}); + + System.out.println(students); + } +} diff --git a/javaSE-day07/src/com/inmind/lambda01/Student.java b/javaSE-day07/src/com/inmind/lambda01/Student.java new file mode 100644 index 0000000..bad1524 --- /dev/null +++ b/javaSE-day07/src/com/inmind/lambda01/Student.java @@ -0,0 +1,19 @@ +package com.inmind.lambda01; + +public class Student { + String name; + int score; + + public Student(String name, int score) { + this.name = name; + this.score = score; + } + + @Override + public String toString() { + return "Student{" + + "name='" + name + '\'' + + ", score=" + score + + '}'; + } +}