s-day02-Collections里面的sort方法以及Comparable接口

2026-08-02 14:34:10 +08:00
parent 3cb9b35ade
commit fc1ab55c40
2 changed files with 78 additions and 0 deletions
@@ -0,0 +1,39 @@
+package com.inmind.collections04;
+
+import java.util.ArrayList;
+import java.util.Collections;
+
+/*
+static <T extends Comparable<? super T>> void sort(List<T> list) 根据其元素的自然排序，按照升序排列指定的列表。
+ */
+public class Demo14 {
+    public static void main(String[] args) {
+        //整数的自然排序，默认升序
+        ArrayList<Integer> lists = new ArrayList<>();
+        Collections.addAll(lists, 111, 22, 32, 4, 555);
+        System.out.println(lists);
+        //对集合进行排序
+        Collections.sort(lists);
+        System.out.println(lists);
+        System.out.println("-------------------------------------");
+        //字符串的默认排序，按照字典排序，按ASCII码值
+        ArrayList<String> strs = new ArrayList<>();
+        Collections.addAll(strs, "ab", "ba", "aa", "ca", "ac","bb");
+        System.out.println(strs);
+        //对集合进行排序
+        Collections.sort(strs);
+        System.out.println(strs);
+
+        //自定义类的排序(Student)
+        ArrayList<Student> students = new ArrayList<>();
+        students.add(new Student("张三1", 18,88));
+        students.add(new Student("张三2", 18,90));
+        students.add(new Student("张三3", 18,93));
+        students.add(new Student("张三4", 18,39));
+        System.out.println(students);
+        //注意：Collections.sort排序时，传入的集合的内容，必须拥有自然排序功能（实现Comparable）
+        Collections.sort(students);
+        System.out.println(students);
+
+    }
+}