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Sanity4J was created to simplify running multiple static code analysis tools on the Java projects. It provides a single entry point to run all the selected tools and produce a consolidated report, which presents all findings in an easily accessible manner.

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HE_EQUALS_USE_HASHCODE

HE: Class defines equals() and uses Object.hashCode() (HE_EQUALS_USE_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
  }