I have two objects, Student and Book. Student has @OneToMany relationship with Book, and Book has only id, name, and publishYear. What i want is to return from Query is this:
select s.name,
b.name,
b.publishYear
from Student s
inner join Book b on s.id = b.studentId
How to return s.name, b.name and b.publishYear with map, so i don't want to return a List but a map. How to do that?
I am assuming you have a method findAll() which returns a list of with StudentBook objects that have properties student name, book name and book publish year.
Now to convert this method to return a map that has as key the book name and as values are book name and book published year to follow the code below:
Map<String, Book> map = studentBookList.stream()
.collect(Collectors.toMap(
StudentBook::getSname(),
new Book(StudentBook::getBname(),
StudentBook::getPublishYear()
)
)
);
