質問編集履歴
2
問題集の内容であることを追記
title
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File without changes
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body
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@@ -4,7 +4,7 @@
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4
4
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5
5
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showメソッドの排他制御が原因でデッドロックになっているということまでは分かっているのですが、排他制御についての理解が乏しく、なぜデッドロックになっているのかが分かっておりません。
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6
6
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7
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-
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7
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+
以下問題集の内容抜粋
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8
8
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```Java
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9
9
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public class Test {
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10
10
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1
コードの修正
title
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body
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@@ -6,45 +6,45 @@
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6
6
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7
7
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8
8
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```Java
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9
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-
1 package deadlock;
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10
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-
2
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11
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-
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9
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+
public class Test {
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12
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-
4
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13
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-
5 public static void main(String[] args) {
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14
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-
6 CountThread c1 = new CountThread();
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15
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-
7 CountThread c2 = new CountThread();
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16
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-
8 c1.setCountThread(c2);
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17
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-
9 c2.setCountThread(c1);
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18
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-
10 c1.start();
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19
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-
11 c2.start();
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20
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-
12 }
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21
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-
13 }
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22
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-
14
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23
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-
15 class CountThread extends Thread {
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24
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-
16 CountThread c;
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25
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-
17 int i = 0;
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26
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-
18
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27
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-
19 public void setCountThread(CountThread c) {
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28
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-
20 this.c = c;
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29
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-
21 }
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30
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-
22
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31
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-
23 public synchronized void display(CountThread c) {
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32
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-
24 try {
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33
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-
25 Thread.sleep(10);
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34
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-
26 c.show();
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35
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-
27 } catch (InterruptedException e) {
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36
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-
28
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37
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-
29 }
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38
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-
30 }
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39
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-
31
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40
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-
32 public synchronized void show() {
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41
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-
33 System.out.println(c.getName());
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42
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-
34 }
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43
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-
35
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44
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-
36 public void run() {
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45
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-
37 display(c);
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46
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-
38 }
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47
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-
39
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48
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-
40 }
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49
10
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11
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+
public static void main(String[] args) {
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12
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+
// TODO 自動生成されたメソッド・スタブ
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13
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+
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14
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+
CountThread c1 = new CountThread();
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15
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+
CountThread c2 = new CountThread();
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16
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+
c1.setCountThread(c2);
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17
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+
c2.setCountThread(c1);
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18
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+
c1.start();
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19
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+
c2.start();
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20
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+
}
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21
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+
}
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22
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+
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23
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+
class CountThread extends Thread {
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24
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+
CountThread c;
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25
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+
int i = 0;
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26
|
+
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|
27
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+
public void setCountThread(CountThread c) {
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28
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+
this.c = c;
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29
|
+
}
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30
|
+
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|
31
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+
public synchronized void display(CountThread c) {
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32
|
+
try {
|
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33
|
+
Thread.sleep(10);
|
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34
|
+
c.show();
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35
|
+
} catch (InterruptedException e) {
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36
|
+
|
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37
|
+
}
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38
|
+
}
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39
|
+
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40
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+
public synchronized void show() {
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41
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+
System.out.println(c.getName());
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42
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+
}
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43
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+
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44
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+
public void run() {
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45
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+
display(c);
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46
|
+
}
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|
47
|
+
|
|
48
|
+
}
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|
49
|
+
|
|
50
50
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```
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