From 705df33287b0d117d90f20d17ffc43ae996ef961 Mon Sep 17 00:00:00 2001
From: xuxin <840198532@qq.com>
Date: Tue, 13 Oct 2026 11:44:08 +0800
Subject: [PATCH] =?UTF-8?q?s-day01--=E5=AD=97=E7=AC=A6=E4=B8=B2=E4=B8=8E?=
 =?UTF-8?q?=E5=9F=BA=E6=9C=AC=E7=B1=BB=E5=9E=8B=E7=9A=84=E8=BD=AC=E6=8D=A2?=
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---
 s-day01/src/com/inmind/wrap06/Demo17.java | 56 +++++++++++++++++++++++
 1 file changed, 56 insertions(+)
 create mode 100644 s-day01/src/com/inmind/wrap06/Demo17.java

diff --git a/s-day01/src/com/inmind/wrap06/Demo17.java b/s-day01/src/com/inmind/wrap06/Demo17.java
new file mode 100644
index 0000000..8818ac7
--- /dev/null
+++ b/s-day01/src/com/inmind/wrap06/Demo17.java
@@ -0,0 +1,56 @@
+package com.inmind.wrap06;
+/*
+    在java中定义了8个与基本类型一一对应的包装类
+    byte        Byte
+    short       Short
+    int         Integer
+    long        Long
+    float       Float
+    double      Double
+    char        Character
+    boolean     Boolean
+
+    包装类是一个类,封装了很多的功能,提供更多的功能去操作,基本类型进行计算
+
+    在jdk1.5版本之后,出现自动拆装箱
+    拆箱:包装类--->基本类型
+    装箱:基本类型--->包装类
+
+    -------------------------------------------------------------
+因为在实际开发中,我们接收用户输入的数据,大部分都是String,但是java中想要区分类型所以我们要学习String---基本类型的转换
+    基本类型---->字符串
+        +""即可
+    字符串----->基本类型
+        包装类名.parseXXX(字符串);
+ */
+public class Demo17 {
+    public static void main(String[] args) {
+        //基本类型---->字符串
+        int i = 10;
+        Integer i1 = 20;//自动装箱
+        String str1 = i1.toString();//----方式1
+        System.out.println(str1);
+        String str = "呵呵" + i;//---- 方式2
+        System.out.println(str);
+
+        //字符串----->基本类型   包装类名.parseXXX(字符串);
+        //String ----->int
+        String s1 = "100";
+        Integer i2 = Integer.parseInt(s1);
+        System.out.println(i2);
+        //String ----->double
+        String s2 = "3.14";
+        double d = Double.parseDouble(s2);
+        System.out.println(d);
+
+        //String ----->boolean
+        String s3 = "false";
+        boolean b = Boolean.parseBoolean(s3);
+        System.out.println(b);
+
+        //String ----->char
+        String s4 = "java";
+        char c = s4.charAt(0);
+        System.out.println(c);
+    }
+}