 a class-specific comparison. The general contract
 is that this comparison should be reflexive, symmetric, and transitive.
 Also, no object reference other than null is equal to null.

 <p>The default implementation returns <code>true</code> only if <code>this ==
 o</code>. See <a href="../../../../../reference/java/lang/Object.html#writing_equals">Writing a correct
 <code>equals</code> method</a>
 if you intend implementing your own <code>equals</code> method.

 <p>The general contract for the <code>equal