Do I need a equals and Hashcode method if my class implements comparable in Java?

Do I need a equals and Hashcode method if my class implements comparable
in Java?

pI found this comment on a
href=http://stackoverflow.com/questions/18389298/can-stringbuffer-objects-be-keys-in-treeset-in-javacan
StringBuffer objects be keys in TreeSet in Java?/a/p pThere are 2
identifying strategies used with Maps in Java (more-or-less)./p pHashing:
An input Foo is converted into a best-as-possible attempt to generate a
number that uniquely accesses an index into an array. (Purists, please
don't abuse me, I am intentionally simplifying). This index is where your
value is stored. There is the likely possibility that Foo and Bar actually
generate the same index value meaning they would both be mapped to the
same array position. Obviously this can't work and so that's where the
equals() method comes in; it is used to disambiguate/p pComparison: By
using a comparative method you don't need this extra disambiguation step
because comparison NEVER produces this collision in the first place. The
only key that Foo is equal to is Foo. A really good idea though is if you
can is to define equals() as compareTo() == 0; for consistency sake. Not a
requirement./p pmy question is as follows: if my class implements
comparable, then does it mean I dont have to override equals and hashcode
method for using my objects as keys in Hash collections. eg/p precodeclass
Person implements Comparablelt;Persongt; { int id; String name; public
Person(int id, String name) { this.id=id; this.name=name; } public int
compareTo(Person other) { return this.id-other.id; } } /code/pre pNow, can
I use my Person objects in Hashable collections?/p