JVM
In depthPlatform
Also known as: Java Virtual Machine
The virtual machine that executes Java bytecode and makes Java platform-independent: "write once, run anywhere".
JVM, explained
Written by EduVerseWhat it is
The JVM (Java Virtual Machine) is the program that actually runs Java code. The compiler turns your source into bytecode, instructions for this virtual machine rather than for a specific processor, and the JVM executes it on whatever operating system it’s installed on. It also cleans up unused memory for you through garbage collection.
Why teams use it
Because each operating system has its own JVM, the same .jar file runs on Windows, macOS and Linux without recompiling. While your program runs, the JVM also compiles frequently used code to native machine code (JIT compilation). And languages like Kotlin and Scala compile to the same bytecode, so they can use the whole Java ecosystem.
An example from work
Your Spring Boot service crashes in production and the log shows java.lang.OutOfMemoryError: Java heap space. That’s the JVM saying it ran out of the memory it was allowed to use. You start by checking the -Xmx setting, which caps the heap size, or by looking for a memory leak.
Our own explanation, not a quote from the book.
In the book
Sentences from The Software Realm, Decoded that mention JVM, exactly as printed.
1 more passages about JVM in the full book
Read every conversation where JVM comes up, with the interactive slides and demos.
Where it fits
Running Java, Kotlin, Scala and Groovy
Coverage in the book
Covered in depth: multiple pages with explanations, examples and simulations.
