Lombok Library in Java

When we speak of Java programming language we always have a silent answer to the boilerplate code it has to generate. To be specific consider POJO classes having getters and setters.

Need for Lombok
To rescue us from boilerplate code, Lombok, which is a popular Java library that helps reduce boilerplate code in your Java projects by providing a set of annotations and code generation tools. These annotations allow you to automatically generate common code patterns like getters, setters, constructors, and more, making your code cleaner and more concise.
Lombok works by plugging into the build process and will auto-generate the Java bytecode into your .class files required to implement the desired behavior, based on the annotations specified.

How to use Lombok in Java project:
To use Lombok in your Java project, you need to include the Lombok dependency in your build system (e.g., Maven or Gradle) and configure your IDE (e.g., IntelliJ IDEA or Eclipse) to recognize Lombok annotations.

  <dependency>
   <groupId>org.projectlombok</groupId>
   <artifactId>lombok</artifactId>
   <optional>true</optional>
  </dependency>

Commonly used Lombok annotations:

1. @Getter and @Setter: These annotations generate getter and setter methods for fields in your class, eliminating the need to write them manually.
2. @ToString: Generates a toString() method that includes the values of all fields in your class, simplifying debugging and logging.
3. @EqualsAndHashCode: Generates equals() and hashCode() methods based on the fields in your class, making it easier to compare objects.
4. @NoArgsConstructor, @RequiredArgsConstructor, and @AllArgsConstructor: These annotations generate constructors with no arguments, constructors with required fields, and constructors with all fields, respectively.
5. @Data: Combines @Getter, @Setter, @EqualsAndHashCode, and @ToString into a single annotation for convenience.
6. @Builder: Generates a builder pattern for your class, allowing you to create instances with a fluent and readable API.
7. @Value: Similar to @Data, but generates immutable classes with final fields and no setters.
8. @Slf4j and @LogX (e.g., @Log4j, @Logback): These annotations provide built-in logging capabilities using various logging frameworks like SLF4J, Log4j, or Logback.
9. @Cleanup: Automatically closes resources like streams or JDBC connections when they go out of scope.
10. @SneakyThrows: Allows you to throw checked exceptions without declaring them in your method's signature.
11. @NonNull: Adds null-checks to your methods to prevent NullPointerExceptions.
12. @Value.Immutable: Generates immutable value objects with minimal code.

Example:
A sample outline of a Java POJO class with @Data annotation used.
The source code will not have boilerplate code but the compiled byte code will have.