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A subscription provides you with full access to view all Packt and licnesed content online, this includes exclusive access to Early Access titles. Depending on the tier chosen you can also earn credits and discounts to use for owning content

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Projects are rarely cancelled, but sometimes it's unavoidable. If an Early Access course is cancelled or excessively delayed, you can exchange your purchase for another course. For further details, please contact us here.

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Can I download the code files for Early Access titles?

We try to ensure that all books in Early Access have code available to use, download, and fork on GitHub. This helps us be more agile in the development of the book, and helps keep the often changing code base of new versions and new technologies as up to date as possible. Unfortunately, however, there will be rare cases when it is not possible for us to have downloadable code samples available until publication.

When we publish the book, the code files will also be available to download from the Packt website.

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The publication date is as accurate as we can be at any point in the project. Unfortunately, delays can happen. Often those delays are out of our control, such as changes to the technology code base or delays in the tech release. We do our best to give you an accurate estimate of the publication date at any given time, and as more chapters are delivered, the more accurate the delivery date will become.

How will I know when new chapters are ready?

We'll let you know every time there has been an update to a course that you've bought in Early Access. You'll get an email to let you know there has been a new chapter, or a change to a previous chapter. The new chapters are automatically added to your account, so you can also check back there any time you're ready and download or read them online.

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What is Early Access?

Keeping up to date with the latest technology is difficult; new versions, new frameworks, new techniques. This feature gives you a head-start to our content, as it's being created. With Early Access you'll receive each chapter as it's written, and get regular updates throughout the product's development, as well as the final course as soon as it's ready.We created Early Access as a means of giving you the information you need, as soon as it's available. As we go through the process of developing a course, 99% of it can be ready but we can't publish until that last 1% falls in to place. Early Access helps to unlock the potential of our content early, to help you start your learning when you need it most. You not only get access to every chapter as it's delivered, edited, and updated, but you'll also get the finalized, DRM-free product to download in any format you want when it's published. As a member of Packt, you'll also be eligible for our exclusive offers, including a free course every day, and discounts on new and popular titles.

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Sergio Sep 20, 2024

And this book will deliver what it promises, you start with Part 1, giving a great view of what we have inside the Java Virtual Machine (or JVM), giving a lesson on how it works, the class structure, bytecode.Then we will talk about Memory, going through how the Execution Engine works, how the JVM deals with Memory, we will talk about Garbage Collection and which one to use and when, how to deal with Memory Profiling, and here you will have a lesson on how How this whole part works and how you can use it to your advantage, with indications of extra reading that will expand your horizons about dealing with memory and GC in Java.Then you will explore the multiple flavors of JVM that you will find out there, such as GraalVM, Eclipse J9, Azul Zulu, Amazon Corretto, and so on. This topic is important for you to understand the diversity of this ecosystem and how it can help you.And it will end with some advanced topics to talk about Reflection and Annotation and also giving a great look at Frameworks.

Amazon Verified review

Otávio Gonçalves de Santana Sep 13, 2024

An excellent book for those who want to learn more about JVM, where the author covers several topics around Java and the JVM.

Tiny May 09, 2024

Great book with step by step guides to use the JVM We all know how early Java had security flaws and issues. This provides comprehensive details about how to get to the next level, empowering your JVM solutions to deliver custom, secured applications. The real power in Java is in the write once, run anywhere methodology that supports multiple functions while maintaining consistent code base, recommend for anyone running any JVM implementations.

Changsheng Yang May 07, 2024

Feefo Verified review

Alexander Motorin Jun 24, 2024

I'm already annoyed by the overuse of the words "seamless" and "pivotal". Everything is f...ign pivotal and seamless in this book. Generally author's vocabulary seems pretty limited, you'll read certain words over and over again until you can't take it anymore. The book is full of obsolete filler passages that gain you absolutely nothing — you're constantly educated that knowing this and that makes you master in dealing with xy, in some places quite laughable remarks even. There are plenty of them. I made it to page 40 and such unprecedented level of utmost poor, repetitive language feels almost infuriating at this point.

Mastering the Java Virtual Machine: An in-depth guide to JVM internals and performance optimization

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