public class SeatDTO implements Serializable {
private Integer carriage;
private Integer seat;
...
CREATE TABLE students (
studentid INT NOT NULL AUTO_INCREMENT
,firstname VARCHAR(20)
,lastname VARCHAR(20)
,grade VARCHAR(10) NOT NULL
,PRIMARY KEY (studentid)
);
@Entity
@Table(name = "students")
public class Student {
private long id;
private String firstName;
private String lastName;
private Grade grade;
private List<Issue> studentIssues;
@Id
@GeneratedValue(strategy = IDENTITY)
@Column(name = "studentid")
public long getId() {
return id;
}
public void setId(long id) {
this.id = id;
}
@Column(name = "firstname")
public String getFirstName() {
return firstName;
}
public void setFirstName(String firstName) {
this.firstName = firstName;
}
@Column(name = "lastname")
public String getLastName() {
return lastName;
}
public void setLastName(String lastName) {
this.lastName = lastName;
}
@ManyToOne(optional=false, cascade = CascadeType.PERSIST)
@JoinColumn (name="grade")
@JsonManagedReference
public Grade getGrade() {
return grade;
}
public void setGrade(Grade grade) {
this.grade = grade;
}
@OneToMany(mappedBy = "student", targetEntity = Issue.class, fetch = FetchType.LAZY)
public List<Issue> getStudentIssues() {
return studentIssues;
}
public void setStudentIssues(List<Issue> studentIssues) {
this.studentIssues = studentIssues;
}
@Override
public String toString() {
return firstName + " " + lastName + " "+ grade.getGrade();
}
}
No row with the given identifier exists
. Что же делать с ней, не подскажите? @Entity
@Table(name = "grades")
public class Grade {
private String grade;
private List<Student> gradeStudents;
@Id
@Column(name = "grade")
public String getGrade() {
return grade;
}
public void setGrade(String grade) {
this.grade = grade;
}
/* @OneToMany(mappedBy = "grade", targetEntity = Student.class, fetch = FetchType.LAZY)
@JsonBackReference
public List<Student> getGradeStudents() {
return gradeStudents;
}
public void setGradeStudents(List<Student> gradeStudents) {
this.gradeStudents = gradeStudents;
}*/
@Override
public String toString() {
return grade;
}
}
INSERT INTO grades (grade) VALUES ('10А');
INSERT INTO grades (grade) VALUES ('10B');
INSERT INTO grades (grade) VALUES ('11C');
INSERT INTO grades (grade) VALUES ('11D');
INSERT INTO students (firstname, lastname, grade)
VALUES ('Maksim', 'Ivanov','10A');
INSERT INTO students (firstname, lastname, grade)
VALUES ('Ivan', 'Maksimov','11B');
Request processing failed; nested exception is javax.persistence.EntityNotFoundException: No row with the given identifier exists: [tk.blindpew123.data.Grade#10A]