Design Patterns and Best Practices in Java

Examples

The code mentioned in the previous example contains duplicated code (code smell). We'll apply the execute around pattern to simplify the code and make it easier to read. A possible refactoring can make use of lambda, as we can see:

publicstaticvoid measurePerformance(Runnable runnable) {  long start = System.currentTimeMillis();  runnable.run();  System.out.println("It took " + (System.currentTimeMillis() -   start) + " ms");}publicstaticvoid main(String[] args) {  Main main = new Main();  List<Integer> array = Arrays.asList(500_000, 499_999);  measurePerformance(() -> array.stream().map(BigInteger::valueOf)  .forEach(x -> main.fib(x)));  measurePerformance(() -> main.memoization(array));}