What happens if we override equals?

Only Override HashCode, Use the default Equals: Only the references to the same object will return true . In other words, those objects you expected to be equal will not be equal by calling the equals method. Only Override Equals, Use the default HashCode: There might be duplicates in the HashMap or HashSet.

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Which is faster equal or contains?

contains() is faster performance-wise than comparing the whole string with string. equals() or string == “blah blah”. I don’t know the inner workings of any of these methods, but logically, it seems like contains() should be faster because it can stop traversing the string after it finds the match.

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