Writing High Performance Java Code

[ghost]

Question:
What coding practices significantly improve Java performance?

[shivrajcodez]

Use primitives > wrappers (avoid boxing)
Avoid unnecessary objects (reduce GC)
Prefer StringBuilder over String concat
Use efficient collections (ArrayList > LinkedList)
Tune GC → G1 Garbage Collector / Z Garbage Collector
Minimize synchronization (use concurrent utils)
Use streams carefully (avoid in hot paths)
Reuse objects / pooling (when needed)
Lazy initialization (load only when required)
Profile first (JMH, VisualVM)