I got a very strange problem when I’m trying to compare 2 Long variables, they always show false and I can be sure they have the same number value by debugging in Eclipse: Both of above 2 return values are object-type Long, which confused me. And to verify that I wrote a main method like this: It prints…
Tag: equals
How could a LinkedHashMap fail to find an entry produced by an iterator?
Under what circumstances given a correct implementation of hashCode and equals() can the following code return false? Answer Most likely scenario I can think of would be even though hashCode is “deterministic”, it may be based on mutable fields. If you change the fields used to compute hashCode af…
java.lang.Comparable and equals
If I implement java.lang.Comparable for a class, do I still have to override the equals() method? Or will the Comparable work for equals as well? If the answer is no, then what if some discrepancy arises? Let’s say the way I term two objects as equal within the equals() method is different from the way …
How should equals and hashcode be implemented when using JPA and Hibernate
How should model class’s equals and hashcode be implemented in Hibernate? What are the common pitfalls? Is the default implementation good enough for most cases? Is there any sense to use business keys? It seems to me that it’s pretty hard to get it right to work in every situation, when lazy fetc…
Generated equals in Webservice Stub
All the generated webservice-stubs from our backend have an equals-method similar to this one: Can someone please explain to me the purpoise of __equalsCalc? I just don’t get it. It is not used somewhere else in the class. The way I see it, it is not null exactly during the calculation of the “equ…