Don't use instanceOf to check equality#2
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November 22, 2012 11:56
By equals contract the equals method must be symmetric. This means that a.equals(b) must be true if and only if b.equals(a) is true. Using instanceOf doesn't grant this.
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By equals contract the equals method must be symmetric, a.equals(b) must be true only if b.equals(a) is true.
If instanceOf operator is used then a superclass can be "equals" to a subclass (superclass.equals(subclass)), but the inverse always return false, because "subclass instanceOf superclass" is always false.
BTW: Great work!