Java Is Fast. Your Code Might Not Be
4 hours ago
- #Java
- #Performance
- #Optimization
- Java performance optimization can significantly improve application speed and efficiency.
- String concatenation in loops leads to O(n²) performance due to immutability; use StringBuilder instead.
- Accidental O(n²) complexity occurs with streams inside loops; optimize by reducing redundant operations.
- String.format() is slow in hot paths; prefer StringBuilder or direct concatenation.
- Autoboxing in hot paths creates unnecessary objects; use primitive types where possible.
- Exceptions for control flow are expensive; pre-validate inputs to avoid throwing exceptions.
- Too-broad synchronization can bottleneck performance; use ConcurrentHashMap or LongAdder for better concurrency.
- Recreating reusable objects like ObjectMapper is inefficient; use static instances instead.
- Virtual thread pinning in JDK 21-23 can stall performance; use ReentrantLock instead of synchronized blocks.
- Performance improvements compound across a fleet of servers, leading to significant cost savings.