回答編集履歴
2
追記
test
CHANGED
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@@ -49,3 +49,43 @@
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49
49
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}
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50
50
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51
51
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```
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52
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+
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53
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+
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54
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55
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+
実例
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56
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57
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---
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58
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59
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+
**ダメな例** (2回目以降の呼び出し時にNoSuchElementExceptionを送出する)
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60
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+
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61
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+
```Java
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62
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63
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+
int read() {
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64
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65
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Scanner sc = new Scanner(System.in);
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66
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67
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int ret = sc.nextInt();
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68
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69
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sc.close();
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70
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71
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return ret;
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72
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+
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73
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}
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74
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75
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```
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76
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77
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78
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79
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**良い例**
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80
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+
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81
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```Java
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82
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+
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83
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int read(Scanner sc) {
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84
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85
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int ret = sc.nextInt();
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86
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87
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return ret;
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88
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+
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89
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}
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90
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91
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```
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1
追記
test
CHANGED
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@@ -9,3 +9,43 @@
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9
9
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10
10
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11
11
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その場合、mainメソッド終了前にcloseしてあげて下さい。
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12
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+
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13
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14
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15
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エラー再現
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16
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17
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---
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18
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19
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+
```Java
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20
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+
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21
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+
import java.util.Scanner;
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22
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+
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23
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+
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24
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+
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25
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class Main {
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26
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27
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public static void main(String[] args) {
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28
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29
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Scanner sc;
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30
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+
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31
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32
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33
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sc = new Scanner(System.in);
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34
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35
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System.out.println(sc.next()); // ここではちゃんと読める
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36
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37
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sc.close();
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38
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+
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39
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+
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40
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+
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41
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sc = new Scanner(System.in);
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42
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+
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43
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+
System.out.println(sc.next()); // エラー!!
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44
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+
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45
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sc.close();
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46
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+
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47
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}
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|
48
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+
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49
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+
}
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50
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+
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51
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+
```
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