Finding the Size of Objects in Java
In Java, the question of determining the memory footprint of an object arises frequently when comparing data structures. However, unlike C/C with its sizeOf() method, Java lacks an explicit method for this purpose.
Solution: Utilizing java.lang.instrumentation
The lack of a built-in method in Java necessitates an alternative approach. One suitable solution is to leverage the java.lang.instrumentation package. This package provides a method that delivers an implementation-specific approximation of an object's size, along with any associated overhead.
Code Example:
The following code snippet demonstrates the usage of the java.lang.instrumentation package to retrieve object sizes:
<code class="java">import java.lang.instrument.Instrumentation; public class ObjectSizeFetcher { private static Instrumentation instrumentation; public static void premain(String args, Instrumentation inst) { instrumentation = inst; } public static long getObjectSize(Object o) { return instrumentation.getObjectSize(o); } }</code>
To determine the size of an object, simply use the getObjectSize method:
<code class="java">public class C { private int x; private int y; public static void main(String [] args) { System.out.println(ObjectSizeFetcher.getObjectSize(new C())); } }</code>
The above is the detailed content of How to Determine the Size of Objects in Java?. For more information, please follow other related articles on the PHP Chinese website!

Start Spring using IntelliJIDEAUltimate version...

When using MyBatis-Plus or other ORM frameworks for database operations, it is often necessary to construct query conditions based on the attribute name of the entity class. If you manually every time...

Java...

How does the Redis caching solution realize the requirements of product ranking list? During the development process, we often need to deal with the requirements of rankings, such as displaying a...

Conversion of Java Objects and Arrays: In-depth discussion of the risks and correct methods of cast type conversion Many Java beginners will encounter the conversion of an object into an array...

Solutions to convert names to numbers to implement sorting In many application scenarios, users may need to sort in groups, especially in one...

Detailed explanation of the design of SKU and SPU tables on e-commerce platforms This article will discuss the database design issues of SKU and SPU in e-commerce platforms, especially how to deal with user-defined sales...

How to set the SpringBoot project default run configuration list in Idea using IntelliJ...


Hot AI Tools

Undresser.AI Undress
AI-powered app for creating realistic nude photos

AI Clothes Remover
Online AI tool for removing clothes from photos.

Undress AI Tool
Undress images for free

Clothoff.io
AI clothes remover

Video Face Swap
Swap faces in any video effortlessly with our completely free AI face swap tool!

Hot Article

Hot Tools

MantisBT
Mantis is an easy-to-deploy web-based defect tracking tool designed to aid in product defect tracking. It requires PHP, MySQL and a web server. Check out our demo and hosting services.

Dreamweaver Mac version
Visual web development tools

SublimeText3 Mac version
God-level code editing software (SublimeText3)

PhpStorm Mac version
The latest (2018.2.1) professional PHP integrated development tool

WebStorm Mac version
Useful JavaScript development tools