Anti-patterns related to unnecessary object creation that can lead to performance issues.
Excessive Object Creation Overview
Creating objects in programming languages with automatic memory management (like Java, JavaScript, Python, etc.) has a cost that is often overlooked. Each object allocation requires memory, initialization time, and eventually triggers garbage collection when the object is no longer needed.
Excessive object creation can lead to:
This guide covers common anti-patterns related to unnecessary object creation, along with best practices for minimizing object allocation overhead across different programming languages and application types.
Creating Objects in Tight Loops
Creating objects within tight loops, especially in performance-critical code, can lead to significant overhead due to memory allocation, initialization, and increased garbage collection pressure.
To avoid unnecessary object creation in loops:
Inefficient String Manipulation
Inefficient string manipulation, particularly concatenation in loops, leads to excessive object creation due to the immutable nature of strings in most programming languages.
To optimize string manipulation:
Temporary Objects in Stream Processing
Stream and collection processing operations often create unnecessary intermediate objects, especially when using boxed types or when chaining multiple transformations that create temporary objects.
To optimize stream and collection processing:
Unnecessary Defensive Copies
Making defensive copies of collections or objects is a common practice to ensure encapsulation and immutability, but excessive or unnecessary defensive copying can lead to significant object creation overhead.
To optimize defensive copying:
Excessive Use of Autoboxing
Autoboxing (automatic conversion between primitive types and their wrapper classes) can lead to excessive object creation, especially in loops or other performance-critical code paths.
To minimize autoboxing overhead:
Inefficient Date/Time Object Creation
Date and time objects are often expensive to create and parse, especially when done repeatedly in loops or when using older APIs that create multiple intermediate objects.
To optimize date/time handling:
Excessive Use of Regular Expressions
Regular expressions are powerful but can be expensive to compile and execute. Creating new regex pattern objects repeatedly, especially in loops or frequently called methods, leads to unnecessary object creation and performance overhead.
To optimize regular expression usage:
Inefficient Collection Conversions
Converting between different collection types (lists, maps, sets, arrays) often involves creating new collection objects and copying elements, which can be expensive, especially for large collections or when done frequently.
To optimize collection conversions:
Inefficient Object Serialization
Inefficient object serialization, such as serializing objects individually or recreating serialization infrastructure for each operation, can lead to excessive object creation and poor performance.
To optimize serialization:
Object Creation Best Practices Checklist
Minimizing unnecessary object creation is a key aspect of optimizing application performance, especially in garbage-collected languages. By following best practices for object creation and reuse, you can reduce memory pressure, minimize garbage collection pauses, and improve overall application throughput.
Key principles for efficient object creation: