【Java 基础篇】【第二课】基本数组类型

  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 }