JHipster Post REST API Displays SQL Error - spring

Question

i am creating a project with using JHipster.
I have 2 entity(Course,Student) and they have many-to many relation.
So there is an another entity called Course_Student and it has 2 column(student_id,course_id).
Students(users) need to register course with clicking Register Course button on their own panel.
So i wrote a query and rest API function.
Here is my Query function:
#Modifying
#Query(value="insert into COURSE_STUDENT (STUDENTS_ID, COURSES_ID) VALUES (:studentId,:courseId)",nativeQuery = true)
#Transactional
void registerCourse(#Param("studentId") Long studentId, #Param("courseId") Long courseId);
And Rest API function:
#PostMapping("/registercourse/{studentId}/{courseId}")
#Timed
public ResponseEntity<Void> registerCourse(#PathVariable Long studentId,#PathVariable Long courseId) {
log.debug("REST request to register {} Course : {} Student : {}", courseId,studentId);
courseRepository.registerCourse(studentId,studentId);
return ResponseEntity.ok().headers(HeaderUtil.createEntityCreationAlert(ENTITY_NAME, courseId.toString())).build();
}
But when i try to run registerCourse API with Using Swagger console displays these errors: (i entered student id:33, course id: 1)
c.m.m.w.rest.errors.ExceptionTranslator : An unexpected error occurred: could not execute statement; SQL [n/a]; constraint ["FK_COURSE_STUDENT_COURSES_ID: PUBLIC.COURSE_STUDENT FOREIGN KEY(COURSES_ID) REFERENCES PUBLIC.COURSE(ID) (33)"; SQL statement:
insert into COURSE_STUDENT (STUDENTS_ID, COURSES_ID) VALUES (?,?) [23506-196]]; nested exception is org.hibernate.exception.ConstraintViolationException: could not execute statement
org.springframework.dao.DataIntegrityViolationException: could not execute statement; SQL [n/a]; constraint ["FK_COURSE_STUDENT_COURSES_ID: PUBLIC.COURSE_STUDENT FOREIGN KEY(COURSES_ID) REFERENCES PUBLIC.COURSE(ID) (33)"; SQL statement:
insert into COURSE_STUDENT (STUDENTS_ID, COURSES_ID) VALUES (?,?) [23506-196]]; nested exception is org.hibernate.exception.ConstraintViolationException: could not execute statement
at org.springframework.orm.jpa.vendor.HibernateJpaDialect.convertHibernateAccessException(HibernateJpaDialect.java:278)
Caused by: org.hibernate.exception.ConstraintViolationException: could not execute statement
at org.hibernate.exception.internal.SQLStateConversionDelegate.convert(SQLStateConversionDelegate.java:112)
... 145 common frames omitted
Caused by: org.h2.jdbc.JdbcSQLException: Referential integrity constraint violation: "FK_COURSE_STUDENT_COURSES_ID: PUBLIC.COURSE_STUDENT FOREIGN KEY(COURSES_ID) REFERENCES PUBLIC.COURSE(ID) (33)"; SQL statement:
insert into COURSE_STUDENT (STUDENTS_ID, COURSES_ID) VALUES (?,?) [23506-196]
at org.h2.message.DbException.getJdbcSQLException(DbException.java:345)
... 163 common frames omitted
2017-09-08 08:58:57.099 WARN 7528 --- [ XNIO-2 task-8] .m.m.a.ExceptionHandlerExceptionResolver : Resolved exception caused by Handler execution: org.springframework.

Answer 1

You are passing the student_id as the course_id, and no course exists with the id of 33. See the 3rd line of your Rest API's registerCourse:
courseRepository.registerCourse(studentId,studentId);
change to:
courseRepository.registerCourse(studentId,courseId);