What is the Lombok library and how is it used in Java?

Lombok is a library that automatically generates boilerplate code for Java classes, such as getters, setters, constructors, equals(), hashCode(), and toString() methods. This is achieved through the use of annotations.

Examples of usage:

• @Getter / @Setter: Automatic generation of getters and setters for class fields.
• @NoArgsConstructor, @RequiredArgsConstructor, @AllArgsConstructor: Automatic generation of various types of constructors.
• @ToString: Generation of the toString() method.
• @EqualsAndHashCode: Generation of equals() and hashCode() methods.
• @Data: A shortcut that combines @Getter, @Setter, @ToString, @EqualsAndHashCode, and @RequiredArgsConstructor.
• @Builder: Implementation of the Builder pattern.
• @Value: An immutable version of @Data (fields are final, setters are removed).

Advantages of Lombok:

• Reduces code volume.
• Improves readability.
• Decreases the likelihood of errors when writing boilerplate code manually.

Disadvantages of Lombok:

• Requires IDE configuration for proper annotation support.
• Some dependency on the library, which may complicate migration or future removal.
• Debugging generated code can be less intuitive.

Example code using Lombok:

// import lombok.Data;

// @Data
// public class User {
//     private Long id;
//     private String name;
//     private int age;
// }

Without Lombok, this class would look approximately like this:

// public class User {
//     private Long id;
//     private String name;
//     private int age;

//     public User() {
//     }

//     public User(Long id, String name, int age) {
//         this.id = id;
//         this.name = name;
//         this.age = age;
//     }

//     public Long getId() {
//         return id;
//     }

//     public void setId(Long id) {
//         this.id = id;
//     }

//     public String getName() {
//         return name;
//     }

//     public void setName(String name) {
//         this.name = name;
//     }

//     public int getAge() {
//         return age;
//     }

//     public void setAge(int age) {
//         this.age = age;
//     }

//     @Override
//     public boolean equals(Object o) {
//         if (this == o) return true;
//         if (o == null || getClass() != o.getClass()) return false;
//         User user = (User) o;
//         if (age != user.age) return false;
//         if (!id.equals(user.id)) return false;
//         return name.equals(user.name);
//     }

//     @Override
//     public int hashCode() {
//         int result = id.hashCode();
//         result = 31 * result + name.hashCode();
//         result = 31 * result + age;
//         return result;
//     }

//     @Override
//     public String toString() {
//         return "User{" +
//                 "id=" + id +
//                 ", name='" + name + '\'' +
//                 ", age=" + age +
//                 '}';
//     }
// }