18 lines
567 B
Java
18 lines
567 B
Java
// understandingcollections/Groundhog2.java
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// (c)2016 MindView LLC: see Copyright.txt
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// We make no guarantees that this code is fit for any purpose.
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// Visit http://OnJava8.com for more book information.
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// A class that's used as a key in a HashMap
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// must override hashCode() and equals()
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public class Groundhog2 extends Groundhog {
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public Groundhog2(int n) { super(n); }
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@Override
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public int hashCode() { return number; }
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@Override
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public boolean equals(Object o) {
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return o instanceof Groundhog2 &&
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(number == ((Groundhog2)o).number);
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}
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}
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