LinkedHashSet.remove() not Working?

[Aaron Davies]

I'm having a very weird problem. Under J2SE5.0b2,
LinkedHashSet.remove(Object) doesn't seem to be working right. I have
an object which I know is present in the
set--set.toArray()[0].equals(o) returns true--but set.remove(o)
returns false. If I change the collection to use a List, it all works
fine. This is bizzare. Any ideas?

 

[Andrew Thompson]

Any ideas?

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2) Post to *one* group that is most appropriate,
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[Filip Larsen]

Aaron Davies wrote

I'm having a very weird problem. Under J2SE5.0b2,
LinkedHashSet.remove(Object) doesn't seem to be working right. I have
an object which I know is present in the
set--set.toArray()[0].equals(o) returns true--but set.remove(o)
returns false. If I change the collection to use a List, it all works
fine. This is bizzare. Any ideas?

Perhaps the hashCode method on the object is not implemented to match
the semantics of the equals method?


Regards,

 

[Thomas Weidenfeller]

I'm having a very weird problem. Under J2SE5.0b2,
LinkedHashSet.remove(Object) doesn't seem to be working right. I have
an object which I know is present in the
set--set.toArray()[0].equals(o) returns true--but set.remove(o)
returns false. If I change the collection to use a List, it all works
fine. This is bizzare. Any ideas?

You key is not immutable? Did you change it after you added it to the
hash? Is you hash code of the element changing and doesn't match your
equals() implementation?

/Thomas