Android(java)学習ノート97:Scanner類使用
7268 ワード
1 package cn.itcast_01;
2
3 /*
4 * Scanner: 。
5 *
6 * ：
7 * A:
8 * B:
9 * C:
10 *
11 * System ：
12 * public static final InputStream in; ， 。
13 *
14 * InputStream is = System.in;
15 *
16 * class Demo {
17 * public static final int x = 10;
18 * public static final Student s = new Student();
19 * }
20 * int y = Demo.x;
21 * Student s = Demo.s;
22 *
23 *
24 * ：
25 * Scanner(InputStream source)
26 */
27 import java.util.Scanner;
28
29 public class ScannerDemo {
30 public static void main(String[] args) {
31 //
32 Scanner sc = new Scanner(System.in);
33
34 int x = sc.nextInt();
35
36 System.out.println("x:" + x);
37 }
38 } 1 package cn.itcast_02;
2
3 import java.util.Scanner;
4
5 /*
6 * ：
7 * public boolean hasNextXxx():
8 * public Xxx nextXxx():
9 *
10 * ： int
11 * public boolean hasNextInt()
12 * public int nextInt()
13 *
14 * ：
15 * InputMismatchException：
16 */
17 public class ScannerDemo {
18 public static void main(String[] args) {
19 //
20 Scanner sc = new Scanner(System.in);
21
22 //
23 if (sc.hasNextInt()) {
24 int x = sc.nextInt();
25 System.out.println("x:" + x);
26 } else {
27 System.out.println(" ");
28 }
29 }
30 }