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A class can override methods that it inherits.

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You saw that the object class is the common ancestor of every class.

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So every class inherits methods from the object class.

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Now, a class can customize, it can override methods that it inherits.

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So in this lesson, you're going to learn to override the equals method.

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When the double equal operator is used for objects, it compares the references, it returns true if

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the references are equal.

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So inside main job, a person to equal to person.

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And then check if person to double eagles person.

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Run the debugger.

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Person to any person share the same reference, so the double equals sign returns true.

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Now what if I said person two equal to a copy of person?

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We run the debugger.

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Person to store is a reference that points to a new object, and because they don't share the same reference,

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then the operator is going to determine that they're not equal.

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That being said, never used a double equals sign to compare objects.

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Remember, that object is the ancestor of every class.

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So by default, our person class is going to inherit this equals method.

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Let's use it and see what happens.

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We'll check if person two equals person one.

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Run the debugger.

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They don't share the same references, they do share the same fields.

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But it returns false.

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If you have another look at the equals method that we're inheriting, it returns true only if the references

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are equal.

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So hear us saying this is no different than saying this person two equals person one.

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You can even confirm this, relaunch the debugger.

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And it steps into the equals method inside the object class.

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And you can see that a default equals method that we're inheriting compares the references of two objects.

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That's why we need to override the equals method.

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Override means to change the logic of an inherited method, you're going to customize, you're going

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to override the equals method for the person class.

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You already know how to override an equals method.

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You've done it a million times before.

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All we have to do is replicate the signature of the equals method we're inheriting.

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And here we can write to whatever we want, we could print high and return false.

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But the point is, we overrode the equals method and JAV is now going to use this one instead, try

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it out, run the debugger and it calls the equals method we overrode.

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Now, there's a much easier way to override equals, just the right equals, and let Intellisense autocomplete

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the method for you and beautiful.

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Don't worry about what super is for now remove it.

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And now we can customize the equals method, just like we always do, if the object being passed in

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is No.

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Return false.

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If it's not an instance of the person class return false.

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If it is typecast, the object to person.

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And then compare the fields of the current object that's calling this method to the one that's being

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passed in return, the Stone Age equals person H.

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We're going to have to add some Gedda's first, let's do just that.

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And good.

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Now, the override annotation means we're overriding a method that we inherited.

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You don't have to include it.

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Remember, in the past, we never did, but you should leave it.

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Because if you misspell the method, it's going to throw an error and say there's no method equal to

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override, so that's good to have.

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Now, if you rerun the code, the person object calls the overwritten equals method.

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Let's recap, you overrode the equals method.

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Override it means changing the logic of an inherited method when you override a method, Jarvis starts

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using that one instead.