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This is a way of how to implement the observable pattern in your code.

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Basically, you need to have either an abstract class or an interface in a defined in your code for

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the object will abstract object here.

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You will need to use Generex because it's better not to have a specific object here.

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You maybe will need to refactor your object to create another type of object.

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So it's better to to define it.

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Using Generex also, you will need to have either a Hashmat or a hash table to story or objects and

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the status for each of them.

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Maybe if you will check out an object, you'll not need the object anymore.

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You'll be needing to to store this object in this hash table or Hashmat and put it a billion value or

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whatever, whatever value you will mark your object with.

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Just you, you know, make it unavailable to make it checked out for for you or for your program not

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to use that specific object.

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Hash table or hash maps are preferred because of their performance of receiving data of retrieving the

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objects.

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So this is the way to go.

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Also, there is the create method here, which needs to be abstract.

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You will need to implement your own method and object to a concrete object, concrete class.

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So this you'll find less articles and explanations on how to get them out.

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And especially if you compare this chapter, which are more popular, if you will just put your object

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in the hash table that we define here with the status of force.

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So this object will be marked as not available for your program.

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And but of course, you you can define your own method to put these objects back into production.

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So that's not a limitation of of this pattern.

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And also for checking in, you will just search for your hash table here in your hash table.

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You will search for an object that has a status positive, that has a status through.

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So this object will be returned, otherwise no will be returned.

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But this is just for simplicity.

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You can have any any anything here, any type of object that you may be returning a basic T object if

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you want to.

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Also, you can see the synchronous keyword has been used for both methods because as I said, this object

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pattern can be can cause some problems in terms of multi threading.

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So if you're using if your program is running in a multi trading environment, if you're performing

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several tasks at once, you may have some problems when checking in and out specific objects.

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This is the robot's pool class that will extend the object pool.

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So I'll be using the robot's class that I define in a previous Loreal.

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And here we have to create.

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As you can see, the great method will assign I will create a new robot, will assign a random ID here,

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will create an empty array list and an empty set of components.

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The array list was for the features of the robot.

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We may not know at the creation time what will what the features for the robot will be.

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So it's better to create some imperialist and empty components, whatever, whatever properties your

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class have, because then at the wrong time you may need to populate those those properties.

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But at the beginning you just created the object and then the program will handle the details for or

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for this particular object.

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I will recap a bit the robot class as well.

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You can see there are only three properties here.

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A constructor try to mimic more complex object by putting a more complex constructor with more than

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two properties and also gethers in setters for each and every one, the colonial.

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However, the implementation of the control interface is not needed anymore.

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So this is the only difference in this code between this tutorial and the previous one.

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And the components class hasn't been changed.

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So basically we have two strings, two properties, name and functionality and get.

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And there's for each of them.

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And as you can see in the app class, we just create a new robot ball and we create our first robot

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by calling the create method from inside the robot pool.

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And the second robot will be created using the same method.

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But however, we do some some tasks here between these lines and we decide that we need to decommission

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our first robot.

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So what we need to do is to check this out, to call the check out method.

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And as a as an argument, we will supply the name of the object that we want to check out.

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This is pretty straightforward and this is also available.

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So we're checking in a new a new robot.

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This will be the checking method will be called and a new robot will be returned as the third robot.

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So this is kind of it.

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It's pretty.

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It's pretty complex.

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This is an overly simplified example.

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But things in real life tend to be very complex and use case for this might be when you will you need

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to maybe to connect to a specific database and you might need an object for that.

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You may need an object for creating a data connection to my school or a school or whatever your database

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provider is.

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And an object can be used for that.

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But as I said in the previous video, it's better to have a single tone object for for the pool.

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And also you may need to apply a design pattern to the create method as well for, you know, just making

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things more intuitive when reading the code.

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So you may apply a factory or a builder pattern for or for a discrete method.

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But as I said, this is a very simplified example here.

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So we won't use we won't make this more complicated than it is.

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That's kind of it.

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So join me in the next tutorial where we are going to discuss about the structural design patterns.

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So see you in the next, Loreal.