Book Image

Mastering the Java Virtual Machine

By : Otavio Santana
Book Image

Mastering the Java Virtual Machine

By: Otavio Santana

Overview of this book

Mastering the Java Virtual Machine is a comprehensive guide that will take you into the heart of Java programming, guiding you through the intricate workings of the Java Virtual Machine (JVM) and equipping you with essential skills to become a proficient Java developer. You’ll start by understanding the JVM, exploring its architecture and how it executes Java code. Through detailed explanations and real-world examples, you’ll gain a deep understanding of JVM internals, enabling you to write efficient and optimized Java applications. As you progress, you’ll delve into memory management and execution, unraveling the complexities of heap and stack management, garbage collection, and memory profiling. You'll learn how memory is allocated and reclaimed in the JVM, as well as how to optimize memory usage and identify performance bottlenecks in your applications. With this knowledge, you’ll be able to create Java programs that are not only robust but also highly performant. By the end of this book, you’ll have the skills needed to excel in Java programming, writing efficient, maintainable code.
Table of Contents (19 chapters)
Free Chapter
1
Part 1: Understanding the JVM
5
Part 2: Memory Management and Execution
9
Part 3: Alternative JVMs
12
Part 4: Advanced Java Topics

Method area

Within the complex architecture of the JVM, the method area serves as a shared space accessible to all JVM threads, much like the storage for compiled code in traditional languages or the “text” segment in an operating system process. This essential region contains structures unique to each class, including the runtime constant pool, data for fields and methods, and the code for methods and constructors. It also accommodates unique class, interface, and instance initialization methods.

Created at the inception of the virtual machine, the method area, while logically part of the heap, may differ in garbage collection and compaction policies. This specification does not dictate its implementation specifics, such as location and management policies, offering flexibility to JVM implementations. The method area’s size, whether fixed or dynamic, can be controlled by the programmer or user, providing flexibility in tuning the runtime environment. However...