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12public
13class SafeStack extends SimpleStack {
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23 public
24 SafeStack(int max) {
25 super(max);
26 }
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30 public
31 SafeStack() {
32 super();
33 }
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41 public
42 Object top()
43 {
44 assert preTop() : "Stack underflow";
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46 return
47 super.top();
48 }
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56 public
57 void pop()
58 {
59 assert preTop() : "Stack underflow";
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61 super.pop();
62 }
63
64}
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66
