Engineers:

1. Follow the Java Naming Conventions

Use meaningful and descriptive names for classes, methods, and variables, following the standard Java naming conventions. This improves code readability and maintainability.

2. Keep Methods Short and Cohesive

Aim for smaller methods that perform a single task. This improves code readability, testability, and makes it easier to understand and modify the code.

3. Write Readable and Self-Documenting Code

Use meaningful variable and method names, write clear comments, and avoid unnecessary or complex code constructs. This helps other developers understand your code easily.

4. Avoid Magic Numbers and Strings

Avoid using hard-coded numbers or strings in your code. Instead, use constants or configuration files to define such values, improving code maintainability and reducing potential bugs.

5. Use Appropriate Exception Handling

Handle exceptions gracefully by catching specific exceptions rather than using generic catch blocks. Provide meaningful error messages and handle exceptions at the appropriate level of abstraction.

6. Use Interfaces and Polymorphism

Utilize interfaces to define contracts and separate implementation details. Favor composition over inheritance and leverage polymorphism to write flexible and maintainable code.

7. Optimize Loops and Collections

Use enhanced for loops (for-each loop) whenever possible to iterate over collections. Prefer the appropriate collection type based on the requirements to optimize performance and memory usage.

8. Utilize Generics

Make use of generics to write type-safe and reusable code. This allows you to provide compile-time safety and avoid unnecessary casting.

9. Minimize Mutable State

Reduce mutable state as much as possible. Immutable objects are easier to reason about and less prone to bugs. Use the final keyword for variables, methods, and classes when appropriate.

10. Use StringBuilder for String Manipulation

When building or manipulating strings, use StringBuilder or StringBuffer instead of concatenating strings with the “+” operator. This improves performance by avoiding unnecessary string object creation.

Instead of string concatenation, consider String.formatted(...) which makes it easier to read the string.

String message = "Successfully processed %d records in %d seconds".formatted(1_100, 10);

11. Avoid Unnecessary Object Instantiation

Be mindful of creating unnecessary objects in your code. Reuse objects or use object pooling techniques when possible, as object creation can be expensive.

12. Implement Proper equals and hashCode

Override the equals() and hashCode() methods appropriately when implementing custom classes. This ensures correct behavior when using collections such as HashMap or HashSet.

Consider using Lombok in your Java POJOs which will add the necessary equals(..) and hashCode() methods.

@Data
public class Person {
    private String firstName;
    private String lastName;
    private int age;
}

See @Data example.

Alternatively, consider using Java 9+ record feature. The above POJO can be rendered as:

public record Person(String firstName, String lastName, int age) {}

13. Properly Manage Resources

When dealing with I/O operations or resources like files, database connections, or network sockets, make sure to properly close or release them using try-with-resources or try-finally blocks.

14. Write Unit Tests

Emphasize the importance of writing unit tests for your code. Use frameworks like JUnit to automate testing and ensure the correctness of your code. Aim for high code coverage to catch potential issues early.

15. Follow SOLID Principles

Encourage adherence to SOLID principles, which include:

• Single Responsibility
• Open/Closed
• Liskov Substitution
• Interface Segregation
• Dependency Inversion

These principles promote modular and maintainable code.

Final Note:

Remember, these best practices are not exhaustive, and there may be additional practices specific to your project or organization. It’s crucial to continuously learn, adapt, and improve coding practices based on evolving industry standards and feedback from peers.