--- title: "3 Advanced Java Best Practices" source: "https://orlandolorenzodeveloper.medium.com/3-advances-java-best-practices-ac7d02a55432" author: - "[[Lorenzo Orlando | Kreyzon Custom Software]]" published: 2024-10-01 created: 2024-10-29 description: "Hello everyone, today we’re diving deep in some advanced Java best practices. Let’s start right away. Java 8 introduced streams and lambda expressions, which allow for cleaner, functional-style code…" tags: - "clippings" --- [ ![Lorenzo Orlando | Kreyzon Custom Software](https://miro.medium.com/v2/resize:fill:88:88/1*RHRLTs-zRl19nGgDF230og.png) ](https://orlandolorenzodeveloper.medium.com/?source=post_page---byline--ac7d02a55432--------------------------------) ![](https://miro.medium.com/v2/resize:fit:700/1*Ac8yn8qIWLfRfS8JeIY_pw.png) Hello everyone, today we’re diving deep in some advanced Java best practices. Let’s start right away. ## 1\. Use Streams and Lambda Expressions Efficiently **Why?** Java 8 introduced streams and lambda expressions, which allow for cleaner, functional-style code. While they are powerful, improper use can lead to performance overhead and complexity. **Best Practices:** - Avoid creating multiple intermediate Stream operations like `filter()` and `map()` if not necessary, as they can add overhead. - Leverage **parallel streams** for CPU-bound tasks but avoid them for I/O-bound tasks (due to context switching). - Prefer `**forEach()**` for side effects like logging, but use terminal operations like `collect()` for transforming data. **Example** ``` List names = employees.stream() .filter(e -> e.getAge() > 30) .map(Employee::getName) .collect(Collectors.toList()); ``` ## 2\. Minimize Synchronization and Leverage Concurrency Utilities **Why?** Java provides a rich set of concurrency utilities like `ExecutorService`, `ForkJoinPool`, and `CompletableFuture`. Using these properly avoids blocking and bottlenecks in multi-threaded applications. **Best Practices:** - Use `**ConcurrentHashMap**` over synchronized collections for thread-safe operations with better performance. - Utilize **optimistic locking** (e.g., `java.util.concurrent.atomic` package) instead of traditional `synchronized` blocks. - Leverage **non-blocking algorithms** and modern concurrency utilities like `CompletableFuture` for asynchronous processing. **Example** ``` CompletableFuture future = CompletableFuture.runAsync(() -> { processData();}, executorService); ``` ## 3\. Apply Design Patterns and Immutability Smartly **Why?** Design patterns like **Singleton**, **Factory**, and **Builder** ensure better object management, while immutability improves thread-safety and reduces side effects. **Best Practices:** - Ensure **immutability** in frequently used objects to make them thread-safe without requiring synchronization. - Use **Factory Pattern** to encapsulate object creation, making the code more flexible and testable. - Apply the **Builder Pattern** for constructing complex objects, making the code cleaner and avoiding telescoping constructors. **Example** ``` public class User { private final String name; private final int age; private User(Builder builder) { this.name = builder.name; this.age = builder.age; } public static class Builder { private String name; private int age; public Builder withName(String name) { this.name = name; return this; } public Builder withAge(int age) { this.age = age; return this; } public User build() { return new User(this); } }}User user = new User.Builder().withName("John").withAge(25).build(); ```