Definition of 'equals()' without corresponding definition of 'hashCode()'.
Bad practice - Class defines equals() and uses Object.hashCode()

This class overrides equals(Object), but does not override hashCode(), and inherits the implementation of hashCode() from java.lang.Object (which returns the identity hash code, an arbitrary value assigned to the object by the VM).  Therefore, the class is very likely to violate the invariant that equal objects must have equal hashcodes.
If you don't think instances of this class will ever be inserted into a HashMap/HashTable, the recommended hashCode implementation to use is:

public int hashCode() {
  assert false : "hashCode not designed";
  return 42; // any arbitrary constant will do
}
  Bad practice - Class defines compareTo(...) and uses Object.equals()
Merge pull request #1739 from Danny-Hazelcast/findbugs

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