java数组

 1 package com.array.jun;
 2 
 3 import java.util.Arrays;
 4 import java.util.Scanner;
 5 
 6 public class ArrayTest {
 7 
 8     public static int[] arrayname0;            //定义数组
 9     public static int[] arrayname1 = {0,0,0,0,0};
10     public static int[] arrayname2 = new int[]{1,2,3,4,5,6};    //静态数组初始化
11     public static int[] arrayname3 = new int[10];                //动态数组初始化
12     
13     public static void arrayTest1(){
14         for (int i : arrayname1) {
15             System.out.print(arrayname1[i] + " ");    //foreach遍历第一个静态初始化数组没问题，第二种会抛出数组越界异常
16         }
17         System.out.println();
18         for (int i = 0; i < arrayname2.length; i++) {
19             System.out.print(arrayname2[i] + " ");    //for遍历都没问题
20         }
21         System.out.println("\n" + arrayname2[1]);
22     }
23     
24     public static void arrayTest2() {        //测试数组静态工具类方法
25         System.out.println(Arrays.binarySearch(arrayname2, 3));
26         System.out.println(Arrays.binarySearch(arrayname2, 2, 4, 3));    //按值索引    binarySearch(a, fromIndex, toIndex, key)
27         int[] array_b = Arrays.copyOf(arrayname2, 4);
28 //        int[] array_b = Arrays.copyOfRange(arrayname2, 2, 5);            //数组元素复制
29         System.out.println(Arrays.toString(array_b));                    //tostring
30         System.out.println(Arrays.equals(array_b, arrayname1));         //equals比较相等
31         Arrays.fill(arrayname3, 4);                                        //填充
32         System.out.println(Arrays.toString(arrayname3));
33         Arrays.sort(arrayname2);                                        //排序
34     }
35     
36     public static void test(){                        //测试方法，方便回调
37         Scanner scan = new Scanner(System.in);
38         switch (scan.nextInt()) {
39         case 0:
40             arrayTest1();
41             break;
42         case 1:
43             arrayTest2();
44             break;
45         default:
46             {
47                 System.out.println("请重新输入！");
48                 test();
49             }
50             break;
51         }
52     }
53     
54     public static void main(String[] args) {
55         // TODO Auto-generated method stub
56         test();
57     }
58 
59 }

案例：

 1 package com.array.jun;
 2 
 3 import java.util.Scanner;
 4 /**
 5  * 
 6  * @author pengjun
 7  * @version 1.0
 8  * 完成一个数字金额转换成人民币读法的工具！
 9  */
10 public class SwitchTools {
11 
12     private static String[] hanzi = {"零","壹","贰","叁","肆","伍","陆","柒","捌","玖"};
13     private static String[] unit = {"十","佰","千","万"};
14     
15     /**
16      * @param num 需要被分解的浮点数
17      * @param zheng 整数部分
18      * @param xiao 小数部分
19      * @return 返回一个含整数和小数字符串数组
20      */
21     public static String[] getNum(double num){
22         long zheng = (long)num;
23         long xiao = (long)Math.round((num - zheng) * 100);
24         return new String[]{zheng + "",String.valueOf(xiao)};
25     }
26     
27     /**
28      * @param stringNum 被分解的字符串数组
29      * @param numLen0 整数长度
30      * @param numLen1 小数长度
31      * @return result 拼接字符串
32      */
33     public static String readNum(String[] stringNum){
34         String result = "";
35         int numLen0 = stringNum[0].length();
36         for (int i = 0; i < numLen0; i++) {
37             int num0 = stringNum[0].charAt(i) - 48;
38             if (i != numLen0 - 1 && num0 != 0) {
39                 result += hanzi[num0] + unit[numLen0 - i - 2];
40             } else {
41                 result +=hanzi[num0];
42             }
43         }
44         
45         result += "点";
46         int numLen1 = stringNum[1].length();
47         for (int j = 0; j < numLen1; j++) {
48             int num1 = stringNum[1].charAt(j) - 48;
49             result +=hanzi[num1];
50         }
51         
52         return result;
53     }
54     
55     public static void test(){
56         Scanner scan = new Scanner(System.in);
57         double num = scan.nextDouble();
58         System.out.println(readNum(getNum(num)));
59     }
60     
61     public static void main(String[] args) {
62         // TODO Auto-generated method stub
63         test();
64     }
65 
66 }