Java: Basic Code Optimisation Techniques

Improving Code Performance in Java

Whether you’re developing for enterprise systems or resource-constrained environments, following best practices can significantly improve execution speed, reduce memory consumption, and enhance overall system performance.

Avoid Creating Unnecessary Objects

Excessive object creation puts pressure on the Garbage Collector (GC) and consumes memory.

Reuse objects when possible, and use object pooling for frequently used resources.

For frequently used immutable objects, use constants or reuse instances.

String commonString = "reuse me";  // Avoid unnecessary object creation

Use StringBuilder for String Concatenation

String concatenation using + creates multiple String objects, which is inefficient in loops.

Use StringBuilder for mutable strings, especially in loops.

StringBuilder sb = new StringBuilder();
for (int i = 0; i < 1000; i++) {
    sb.append(i);
}

Leverage Primitive Types Whenever Possible