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Hopefully by this point,

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it's starting to click that
everything in Java is an object.

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But what sort of functionality
do we get from the object class?

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Up in the main method,
let's clear out what we've got and

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start fresh with a new dog variable.

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Dog, name it dog = new Dog.

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Then let's add a line and
type dog., to look at our options.

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Here, everything except for
the sound field, and

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the makeSound method comes
from the object class.

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Now, most of these you don't
need to worry about, but

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there's a few you really should know like
equals, hashCode, toString, and getClass.

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Let's start with the getClass method.

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When you call the getClass
method on an object,

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it returns a class object that contains
information about the class itself.

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Like the class name and
what package it's in.

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Moving to the toString method,
when you call toString on an object,

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it returns a string with
information about the object.

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So if we wanted to print
out what was in an object,

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we would use the toString method.

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Hashcode is a little different.

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When you call the hashcode
method on an object,

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you get back an integer
representing that object.

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However, the important thing is
that the hashcode method will

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return a different integer for
every object.

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So one way to check if an object is
equal to another would be to check

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their hashcodes.

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If they've got the same hash code,
they're the same object.

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The other way to check if two objects are
equal would be to use the equals method.

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Which returns a boolean indicating
if the two objects are equal.

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Awesome!

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Back in the code,
lets get some practice with these methods.

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First let's print out the result of
calling toString on our Dog object.

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Let's delete this dog.,
and then type sout,

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and print out dog.toString.

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And then, let's run the app,
and there we go.

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We've got some information
about our object.

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Looks like we've got the class
name followed by an at, and

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then some letters and numbers.

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Let's take a deeper look at the toString
method to figure out what's going on here.

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In IntelliJ, whenever you want to
take a deeper look at something,

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you just put your cursor on it and use
Cmd or Ctrl+B to jump to its declaration.

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Let's click on toString and then hit Cmd
or Ctrl+V, and I'll hide the run pane.

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Here we have the toString
method from the Object class.

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And if we look inside,
we can see that it's returning get class

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dot get name to get the class name,
followed by an at sign.

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And then it looks like that last bit
was just the hash code represented as

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a hex string.

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Also, sometimes when you use Cmd or
Ctrl+B,

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if you're lucky, you'll get some
documentation like we did here.

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We already know most of this
just from reading the code.

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But let's take a look at this bit.

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It is recommended that all
subclasses override this method.

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Override?

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What does that mean?

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We'll find out in the next video.