 from)
where the rating() method comes from:
In the Course entity:
@Column(name = "RATING")
private int rating;
The @Data annotation generates:
- getRating() method - returns the value of the rating field
- setRating(int rating) method - sets the rating field value
So course.getRating() returns the actual rating value (e.g., 5, 4, 3, etc.)
In the CourseNameRating builder:
@Builder
@Data
private static class CourseNameRating {String name;int rating; // ← This field
}
The @Builder annotation generates a builder class with:
- name(String name) method - for setting the name in the builder
- rating(int rating) method - for setting the rating in the builder ← This is where rating() comes from
The flow:
- course.getRating() - gets the rating value from Course entity (e.g., returns 5)
- CourseNameRating.builder().rating(5) - passes that value to the builder's rating() method
- The builder's rating() method sets the rating field in the new CourseNameRating object
So the rating() method exists in the CourseNameRating builder class (generated by @Builder), not in the Course entity. The Course entity has getRating() method (generated by @Data).