From 0646d11dd0f77c82da35472b1a84b1c6d9e3895a Mon Sep 17 00:00:00 2001
From: xuxin <840198532@qq.com>
Date: Thu, 30 Jul 2026 15:44:45 +0800
Subject: [PATCH] =?UTF-8?q?s-day02-=E9=9B=86=E5=90=88=E7=9A=84=E7=BB=A7?=
 =?UTF-8?q?=E6=89=BF=E4=BD=93=E7=B3=BB=E7=AE=80=E8=BF=B0?=
MIME-Version: 1.0
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---
 .../src/com/inmind/collection01/Demo01.java   | 19 +++++++++++++++++++
 .../src/com/inmind/collection01/Demo02.java   | 17 +++++++++++++++++
 2 files changed, 36 insertions(+)
 create mode 100644 s-day02/src/com/inmind/collection01/Demo01.java
 create mode 100644 s-day02/src/com/inmind/collection01/Demo02.java

diff --git a/s-day02/src/com/inmind/collection01/Demo01.java b/s-day02/src/com/inmind/collection01/Demo01.java
new file mode 100644
index 0000000..d362bda
--- /dev/null
+++ b/s-day02/src/com/inmind/collection01/Demo01.java
@@ -0,0 +1,19 @@
+package com.inmind.collection01;
+
+import java.util.ArrayList;
+
+/*
+1.数组是固定不变的保存任意类型数据
+2.集合是长度可变,但是只能保存引用类型
+3.arraylist底层是Object[];
+ */
+public class Demo01 {
+    public static void main(String[] args) {
+        //创建集合添加内容
+        ArrayList<String> list = new ArrayList<>();
+        list.add("wo");
+        list.add("ai");
+        list.add("java");
+        System.out.println(list);
+    }
+}
diff --git a/s-day02/src/com/inmind/collection01/Demo02.java b/s-day02/src/com/inmind/collection01/Demo02.java
new file mode 100644
index 0000000..245ff40
--- /dev/null
+++ b/s-day02/src/com/inmind/collection01/Demo02.java
@@ -0,0 +1,17 @@
+package com.inmind.collection01;
+/*
+Collection 常用功能
+Collection是所有单列集合的父接口，因此在Collection中定义了单列集合(List和Set)通用的一些方法，这些方法可用于操作所有的单列集合。方法如下：
+
+有2个子接口：List和Set
+
+public boolean add(E e)： 把给定的对象添加到当前集合中 。
+public void clear() :清空集合中所有的元素。
+public boolean remove(E e): 把给定的对象在当前集合中删除。
+public boolean contains(E e): 判断当前集合中是否包含给定的对象。
+public boolean isEmpty(): 判断当前集合是否为空。
+public int size(): 返回集合中元素的个数。
+public Object[] toArray(): 把集合中的元素，存储到数组中。
+ */
+public class Demo02 {
+}