1 package a.b;  2   3 public class test   4 {  5   6     static void BasicVariables()  7     {  8         //一、变量的类型的学习  9         System.out.println("一、变量的类型的学习 "); 10          11         // byte 表数范围：-128~127, 存储大小占1byte   12         byte a;  13         a = 12; 14         System.out.println("byte num Is " + a); 15                  16         // int 占4字节 17         int b; 18         b = 66633; 19         System.out.println("int num Is " + b); 20              21         // short 占2字节 22         short c; 23         c = 1234; 24         System.out.println("short num Is " + c); 25          26         // long 占2字节 27         long d; 28         d = 655366; 29         System.out.println("long num Is " + d); 30          31         float e;  32         e = (float)12.6; 33         System.out.println("fload num Is " + e); 34                  35         // int 占4字节 36         double f; 37         f = 33.4; 38         System.out.println("double num Is " +f); 39              40         // short 占2字节 41         char g; 42         g = ‘a‘; 43         System.out.println("char num Is " + g); 44          45         // long 占2字节 46         boolean h; 47         h = true; 48         System.out.println("boolean num Is " + h); 49     } 50      51     static void AboutArrays() 52     { 53         // 二、 数组的学习 54         System.out.println("二、 数组的学习 "); 55          56          57         // 基本类型数组赋值、输出 58         int []a ; 59         a = new int [5]; 60          61         a[0] = a[1] = a[2] = a[3] = a[4] = 9; 62          63         for (int i = 0; i < 5; i++)  64         { 65             System.out.println(a[i]); 66         } 67          68         // 基本类型数组赋值、输出 69         int []b = new int [5]; 70          71         for (int i = 0; i < 5; i++)  72         { 73             b[i] = a[i] + i +1; 74             System.out.println(b[i]); 75         } 76          77         // 基本类型数组初始化时候赋值 78         int []c = new int [] {3,4,5,6,7}; 79                  80         for (int i = 0; i < 5; i++)  81         { 82             System.out.println(c[i]); 83         } 84          85         // 字符数组 86         String []d = new String [] {"you","are","my","small","apple"}; 87                          88         for (int i = 0; i < 5; i++)  89         { 90             System.out.println(d[i]); 91         } 92     } 93      94     public static void main(String[] args) 95     { 96         //一、基本变量 97         BasicVariables(); 98          99         //二、数组100         AboutArrays();101     }102     103     104     105 }

一、变量的类型的学习 byte num Is 12int num Is 66633short num Is 1234long num Is 655366fload num Is 12.6double num Is 33.4char num Is aboolean num Is true二、 数组的学习 99999101112131434567youaremysmallapple