s-day07-使用Lambda表达式简化有参数有返回值的方法(比较器)

2026-08-08 10:18:00 +08:00
parent 6b76e9333a
commit 7db048bd7d
2 changed files with 53 additions and 0 deletions
@@ -0,0 +1,31 @@
+package com.inmind.lambda01;
+
+import java.util.ArrayList;
+import java.util.Collections;
+
+/*
+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<Student> students = new ArrayList<>();
+        students.add(new Student("小王1", 23, 100));
+        students.add(new Student("小王2", 25, 80));
+        students.add(new Student("小王3", 24, 90));
+        //使用比较器对学生集合排序
+        /*Collections.sort(students, new Comparator<Student>() {
+            @Override
+            public int compare(Student o1, Student o2) {
+                return o2.score-o1.score;
+            }
+        });*/
+        //使用lambda表达式简化以上代码
+        Collections.sort(students,(Student o1, Student o2)->{
+            return o1.score-o2.score;
+        });
+
+        System.out.println(students);
+
+    }
+}
@@ -0,0 +1,22 @@
+package com.inmind.lambda01;
+
+public class Student {
+    String name;
+    int age;
+    int score;
+
+    public Student(String name, int age, int score) {
+        this.name = name;
+        this.age = age;
+        this.score = score;
+    }
+
+    @Override
+    public String toString() {
+        return "Student{" +
+                "name='" + name + '\'' +
+                ", age=" + age +
+                ", score=" + score +
+                '}';
+    }
+}