1 package Scanner;
2
3 import java.util.Scanner;
4
5 public class Demo02 {
6 public static void main(String[] args) {
7 //从键盘接收数据
8 Scanner scanner = new Scanner(System.in);
9 System.out.println("使用nextLine方式接收：");
10
11 //判断是否还有输入
12 if (scanner.hasNextLine()){
13 String str = scanner.nextLine();
14 System.out.println("输出的内容为："+ str );
15 }
16 scanner.close();
17 }
18 }
1 package Scanner;
2
3 import java.util.Scanner;
4
5 public class Demo03 {
6 public static void main(String[] args) {
7 Scanner scanner = new Scanner(System.in);
8 System.out.println("请输入数据：");
9 String str = scanner.nextLine();
10 System.out.println("请输出内容：" + str);
11 scanner.close();
12
13 }
14 }
1 package Scanner;
2
3 import java.util.Scanner;
4
5 public class Demo04 {
6 public static void main(String[] args) {
7 Scanner scanner = new Scanner(System.in);
8 //从键盘接收数据
9 int i = 0;
10 float j = 0.0f;
11 System.out.println("请输入整数：");
12 //如果...那么
13 if (scanner.hasNextInt()){
14 i = scanner.nextInt();
15 System.out.println("整数数据："+ i );
16 }else{
17 System.out.println("输入的不是整数数据！");
18 }
19 System.out.println("请输入小数：");
20 if (scanner.hasNextFloat()){
21 j = scanner.nextFloat();
22 System.out.println("小数数据："+ j );
23 }else {
24 System.out.println("输入的不是小数数据！");
25 }
26 scanner.close();
27 }
28 }
1 package Scanner;
2
3 import java.util.Scanner;
4
5 public class Demo05 {
6 public static void main(String[] args) {
7 //我们可以输入多个数字，并求其总和与平均数
8 //每输入一个数字用回车确认，通过输入非数字来结束输入并输出执行结果；
9 Scanner scanner = new Scanner(System.in);//输入非字符就会结束
10
11 double sum = 0;//和
12 int m = 0;//计算输入了多少个数字
13
14 //通过循环判断是否还有输入，并在里面对每一次进行求和和统计
15 while(scanner.hasNextDouble()){
16 double x = scanner.nextDouble();
17 m = m + 1 ;
18 sum = sum + x ;
19 System.out.println("你输入了第"+m+"个数据，当前结果sum="+sum);
20 }
21 System.out.println(m + "个数的和为："+ sum);
22 System.out.println(m + "个数的平均值为："+ (sum/m));
23
24 scanner.close();
25 }
26 }
