27 - Multithreading/013 Homework Multithreading_en.srt

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Hello.

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And this week, we're going to review tasks for multithreaded topic.

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Now you have enough knowledge to deal with them and even more by this moment, we've learned so many

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things that you can solve the same tasks with multiple ways.

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For example, you can solve synchronization task with synchronized Massud, synchronized Bloks Locks

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or Synchronizer.

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And let's review tasks first.

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And after that I will tell you where you can find solution for these tasks in order.

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You could check a solution later.

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So in this file, you can find all home tasks that I recommend to implement to make sure you have enough

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skills in most certain programming.

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We are going to start from the super simple and gradually come to more complex tasks.

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You can find the reference to this file in attachments to the lesson that's reviewed these tasks together,

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and I will give my comments as we go.

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The first task is simple one.

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And just to practice your skills in creating stress in different ways and being able to interrupt threats,

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it is recommended to create and start a threat in four different ways by implementing runnable interface,

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by extending from STREAT class, bypassing the function to constructor of the class and bypassing the

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master reference during the threat objects instantiation.

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All of these ways were revealed in this course, so don't hesitate to navigate between the lessons to

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find the answer to this question.

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The next task is a little bit more complex than the first one, but still, I'm sure it will be easy

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for you to implement.

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You need to create some type that will spam messages with a specified interval of time.

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And also you need to implement logic of threat interruption after enter key press.

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I can give a hint you're here.

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You can try to implement this logic by creating a separate demon threat that would constantly listen

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for new line character.

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Zitter similar to press and enter during the program execution and once new line character is received,

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we interrupt this bomb threat.

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Besides the knowledge of mooches threat, this task also and needs knowledge of input output streams

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in Java.

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In case you have never worked with AI streams, please watch my Java course, namely section about inputs

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and outputs streams in Java.

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The shared task is already about synchronization similar to the ones that we have reviewed in lessons,

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but again seen task solution in the lesson and trying to implement it by itself.

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It is different things.

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So try to implement this task and understand better how SYNCHRONIZE Block works.

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Task number four is a little bit more complex and sure, you have to find a maximum number in multidimensional

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array.

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It is recommended to create Israelian solution and single resolution in order you could see the benefits

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of concurrent compute.

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And also I recommend to solve this task twice in order to practice different things.

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The first variant will be implementation was callable and future objects and the second variant will

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be implementation.

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With Countdown Lache Object.

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Implementing this task force two different ways will let you understand how these two solutions are

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different.

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And what would you prefer to use in your projects?

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And the last but not the least task.

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Number five, the standard task about writers and readers.

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Few students of mine has been asked to implement task and board readers and writers during the interviews.

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This proves that this kind of tasks are popular.

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During the interviews you have to implement reader and writer type and create objects of these types

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that would work together.

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Writer writes to the buffer readers read from above.

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Everything is simple.

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In the case there is nothing in Buffer.

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Something should be written there in case Buffer is full, massages should be consumed.

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There are some specific conditions that I would like you to implement in your solution.

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For example, limit your demo with three cycles of writing and reading.

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Limit your demo to three readers and one writer.

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Only total duration of the program execution should not be longer than two seconds.

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This check is also important.

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In order you do not build logical thread synchronization, only using stress loops similar to the previous

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task.

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I'd like to ask you to implement this task in two different ways.

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The first option is implementation with dummy object that will be used as monitor to synchronize all

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threads.

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Also, you can practice in using weight, modify and modify all methods and the second option is implementation.

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With the API, it would be just perfect for you to understand how to use logs in places where we use

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synchronize blocks and how flexible they are.

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The reference to the source code of the solution to these tasks.

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You can also find in attachments to the lesson in.

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If you already pulled my cloning project, you can find all solutions and different versions of solutions

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in the multiscreen package in Homburg package, all tasks have no in their name.

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So I'm sure it would be easy for you to navigate between them, but try to solve tasks and buy yourself

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first.

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And after that, look at the solution in case for some reasons it is hard for you to solve some task.

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Try to watch less than about a specific topic one more time.

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If this still doesn't help, try to look at a solution and rewrite it.

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As you understood, the things that I am trying to achieve is that you're trying to understand the solution,

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but not just do it.

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And remember, you are going to make a mistakes and that is fine.

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Not learning from that mistakes.

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It is the biggest mistake.

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These are all tasks.

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You are more than welcome to ask questions.

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And as a beginner, in case of any.

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That's it.

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Thank you for your attention and see you in the next Larsons.