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A question about equals() method

avseq anthoy
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Joined: Apr 27, 2004
Posts: 104
Hi!everyone.
I see Sun Certified Programmer for Java 2 Study Guide and it says that if you want objects of your class to be used as keys for a hashtable then you must override equals().But why I can put a class defined by myself into HashTable?

why the following sample has overridden equals() and hashcode() but printed "test null" rather than "test test"?



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Dan Chisholm
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Joined: Jul 02, 2002
Posts: 1865
The C in hashCode should be upper case. You have used lower case characters, so you really did not override the hashCode method.


Dan Chisholm<br />SCJP 1.4<br /> <br /><a href="http://www.danchisholm.net/" target="_blank" rel="nofollow">Try my mock exam.</a>
 
It is sorta covered in the JavaRanch Style Guide.
 
subject: A question about equals() method
 
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