In order to implement Comparable in a class, what method(s) must be defined in that class?
a) equalsb) compares
c) both lessThan and greaterThan
d) compareTo
e) both compares and equals
Answer: d.
Explanation: The Comparable class requires the definition of a compareTo method that will compare two objects and determine if one is equal to the other, or if one is less than or greater than the other and respond with a negative int, 0 or a positive int. Since compareTo responds with 0 if the two objects are equal, there is no need to also define an equals method.
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