Hibernate 5.2.7.Final 및 native Hibernate API를 사용 중입니다. 이제Hibernate 재귀 적 매핑 부모/자식 구조 - 데이터를 가져올 때의 StackOverflowError
Employee manager = new Employee("A", "B");
Employee employee1 = new Employee("C", "D");
Employee employee2 = new Employee("E", "E");
employee1.setManager(manager1);
employee2.setManager(manager1);
Set<Employee> employees = new HashSet<>();
employees.add(employee1);
employees.add(employee2);
manager.setSubordinates(employees);
session.save(manager);
: 나는 성공적으로 관리자와 직원을 계속
+------------+--------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+------------+--------------+------+-----+---------+-------+
| employeeId | bigint(20) | NO | PRI | NULL | |
| firstname | varchar(255) | YES | | NULL | |
| lastname | varchar(255) | YES | | NULL | |
| manager_id | bigint(20) | YES | MUL | NULL | |
+------------+--------------+------+-----+---------+-------+
: 다음 표는 Hibernate에 의해 생성
@Entity
public class Employee {
@Id
@GeneratedValue
private Long employeeId;
@Column
private String firstname;
@Column
private String lastname;
@ManyToOne(cascade={ CascadeType.ALL})
@JoinColumn(name="manager_id")
private Employee manager;
@OneToMany(mappedBy="manager", cascade = CascadeType.ALL)
private Set<Employee> subordinates = new HashSet<Employee>();
// setters, getters, constructors
}
: 나는 재귀 관계를 가진 직원 엔티티를 직원을 검색하면 StackOverFlowError가 발생합니다. 스레드에서
이Long id = manager.getEmployeeId();
Query<Employee> query = ss.createQuery("from Employee e where e.employeeId = :employeeId", Employee.class);
query.setParameter("employeeId", id);
Employee retrieved = (Employee) query.uniqueResult();
예외 "주"java.lang.StackOverflowError의
at java.lang.Long.toString(Long.java:396)
at java.lang.Long.toString(Long.java:1032)
at java.lang.String.valueOf(String.java:2994)
at java.lang.StringBuilder.append(StringBuilder.java:131)
at objectModels.Employee.toString(Employee.java:82)
at java.lang.String.valueOf(String.java:2994)
at java.lang.StringBuilder.append(StringBuilder.java:131)
at objectModels.Employee.toString(Employee.java:82)
at java.lang.String.valueOf(String.java:2994)
at java.lang.StringBuilder.append(StringBuilder.java:131)
at objectModels.Employee.toString(Employee.java:82)
at java.lang.String.valueOf(String.java:2994)
at java.lang.StringBuilder.append(StringBuilder.java:131)
at objectModels.Employee.toString(Employee.java:82)
at java.lang.String.valueOf(String.java:2994)
at java.lang.StringBuilder.append(StringBuilder.java:131)
at objectModels.Employee.toString(Employee.java:82)
at java.lang.String.valueOf(String.java:2994)
at java.lang.StringBuilder.append(StringBuilder.java:131)
at objectModels.Employee.toString(Employee.java:82)
at java.lang.String.valueOf(String.java:2994)
at java.lang.StringBuilder.append(StringBuilder.java:131)
at objectModels.Employee.toString(Employee.java:82)
at java.lang.String.valueOf(String.java:2994)
at java.lang.StringBuilder.append(StringBuilder.java:131)
at objectModels.Employee.toString(Employee.java:82)
at java.lang.String.valueOf(String.java:2994)
at java.lang.StringBuilder.append(StringBuilder.java:131)
at objectModels.Employee.toString(Employee.java:82)
at java.lang.String.valueOf(String.java:2994)
at java.lang.StringBuilder.append(StringBuilder.java:131)
at objectModels.Employee.toString(Employee.java:82)
at java.lang.String.valueOf(String.java:2994)
at java.lang.StringBuilder.append(StringBuilder.java:131)
at objectModels.Employee.toString(Employee.java:82)
at java.lang.String.valueOf(String.java:2994)
at java.lang.StringBuilder.append(StringBuilder.java:131)
at objectModels.Employee.toString(Employee.java:82)
at java.lang.String.valueOf(String.java:2994)
at java.lang.StringBuilder.append(StringBuilder.java:131)
at objectModels.Employee.toString(Employee.java:82)
at java.lang.String.valueOf(String.java:2994)
at java.lang.StringBuilder.append(StringBuilder.java:131)
at objectModels.Employee.toString(Employee.java:82)
at java.lang.String.valueOf(String.java:2994)
at java.lang.StringBuilder.append(StringBuilder.java:131)
at objectModels.Employee.toString(Employee.java:82)
at java.lang.String.valueOf(String.java:2994)
at java.lang.StringBuilder.append(StringBuilder.java:131)
at objectModels.Employee.toString(Employee.java:82)
at java.lang.String.valueOf(String.java:2994)
at java.lang.StringBuilder.append(StringBuilder.java:131)
at objectModels.Employee.toString(Employee.java:82)
at java.lang.String.valueOf(String.java:2994)
at java.lang.StringBuilder.append(StringBuilder.java:131)
at objectModels.Employee.toString(Employee.java:82)
at java.lang.String.valueOf(String.java:2994)
at java.lang.StringBuilder.append(StringBuilder.java:131)
at objectModels.Employee.toString(Employee.java:82)
at java.lang.String.valueOf(String.java:2994)
at java.lang.StringBuilder.append(StringBuilder.java:131)
at objectModels.Employee.toString(Employee.java:82)
at java.lang.String.valueOf(String.java:2994)
at java.lang.StringBuilder.append(StringBuilder.java:131)
at objectModels.Employee.toString(Employee.java:82)
at java.lang.String.valueOf(String.java:2994)
at java.lang.StringBuilder.append(StringBuilder.java:131)
at objectModels.Employee.toString(Employee.java:82)
at java.lang.String.valueOf(String.java:2994)
at java.lang.StringBuilder.append(StringBuilder.java:131)
at objectModels.Employee.toString(Employee.java:82)
at java.lang.String.valueOf(String.java:2994)
at java.lang.StringBuilder.append(StringBuilder.java:131)
at objectModels.Employee.toString(Employee.java:82)
at java.lang.String.valueOf(String.java:2994)
at java.lang.StringBuilder.append(StringBuilder.java:131)
at objectModels.Employee.toString(Employee.java:82)
at java.lang.String.valueOf(String.java:2994)
at java.lang.StringBuilder.append(StringBuilder.java:131)
at objectModels.Employee.toString(Employee.java:82)
at java.lang.String.valueOf(String.java:2994)
at java.lang.StringBuilder.append(StringBuilder.java:131)
at objectModels.Employee.toString(Employee.java:82)
at java.lang.String.valueOf(String.java:2994)
at java.lang.StringBuilder.append(StringBuilder.java:131)
at objectModels.Employee.toString(Employee.java:82)
at java.lang.String.valueOf(String.java:2994)
at java.lang.StringBuilder.append(StringBuilder.java:131)
at objectModels.Employee.toString(Employee.java:82)
at java.lang.String.valueOf(String.java:2994)
at java.lang.StringBuilder.append(StringBuilder.java:131)
at objectModels.Employee.toString(Employee.java:82)
at java.lang.String.valueOf(String.java:2994)
at java.lang.StringBuilder.append(StringBuilder.java:131)
at objectModels.Employee.toString(Employee.java:82)
at java.lang.String.valueOf(String.java:2994)
at java.lang.StringBuilder.append(StringBuilder.java:131)
at objectModels.Employee.toString(Employee.java:82)
at java.lang.String.valueOf(String.java:2994)
at java.lang.StringBuilder.append(StringBuilder.java:131)
at objectModels.Employee.toString(Employee.java:82)
at java.lang.String.valueOf(String.java:2994)
at java.lang.StringBuilder.append(StringBuilder.java:131)
at objectModels.Employee.toString(Employee.java:82)
at java.lang.String.valueOf(String.java:2994)
at java.lang.StringBuilder.append(StringBuilder.java:131)
at objectModels.Employee.toString(Employee.java:82)
at java.lang.String.valueOf(String.java:2994)
at java.lang.StringBuilder.append(StringBuilder.java:131)
at objectModels.Employee.toString(Employee.java:82)
at java.lang.String.valueOf(String.java:2994)
at java.lang.StringBuilder.append(StringBuilder.java:131)
at objectModels.Employee.toString(Employee.java:82)
at java.lang.String.valueOf(String.java:2994)
at java.lang.StringBuilder.append(StringBuilder.java:131)
at objectModels.Employee.toString(Employee.java:82)
at java.lang.String.valueOf(String.java:2994)
at java.lang.StringBuilder.append(StringBuilder.java:131)
at objectModels.Employee.toString(Employee.java:82)
at java.lang.String.valueOf(String.java:2994)
at java.lang.StringBuilder.append(StringBuilder.java:131)
at objectModels.Employee.toString(Employee.java:82)
at java.lang.String.valueOf(String.java:2994)
at java.lang.StringBuilder.append(StringBuilder.java:131)
at objectModels.Employee.toString(Employee.java:82)
at java.lang.String.valueOf(String.java:2994)
at java.lang.StringBuilder.append(StringBuilder.java:131)
at objectModels.Employee.toString(Employee.java:82)
at java.lang.String.valueOf(String.java:2994)
at java.lang.StringBuilder.append(StringBuilder.java:131)
at objectModels.Employee.toString(Employee.java:82)
at java.lang.String.valueOf(String.java:2994)
at java.lang.StringBuilder.append(StringBuilder.java:131)
at objectModels.Employee.toString(Employee.java:82)
at java.lang.String.valueOf(String.java:2994)
at java.lang.StringBuilder.append(StringBuilder.java:131)
at objectModels.Employee.toString(Employee.java:82)
at java.lang.String.valueOf(String.java:2994)
at java.lang.StringBuilder.append(StringBuilder.java:131)
at objectModels.Employee.toString(Employee.java:82)
at java.lang.String.valueOf(String.java:2994)
나는 같은 Employee 객체 그래프를 지속 할 수있는 방법은 매우 편리하다고 생각합니다. 하지만 테이블에서 그런 그래프를 검색하는 방법을 모르겠다.
질문 : 의미있는 방법으로 원본 테이블에서 직원 정보를 검색 할 수 있습니다. 나는 그 방법이 Employee 테이블을보기 위해 새로운 엔티티를 만드는 것이라고 생각한다.
public class EmployeeView {
private Long employeeId;
private String firstname;
private String manager_name;
private Set<String> subordinate_names;
}
내가 이것을 할 수 있을까? JPA 주석은 어떻게 사용합니까?
StackOverflowError 스택 추적을 포함 할 수 있습니까? 또한 5.2.7에서 재현 할 수 없기 때문에 Hibernate의 어떤 버전을 테스트하고있다. 최종. – Naros
스택 추적을 포함 시켰습니다. 나는 StackOverflowError가 직원 객체가 페치되고, 최대 절전 모드로 관리자를 가져오고, 관리자가 부하 직원 목록에 직원을 가지고있을 때 발생한다고 생각한다. @ManyToOne (fetch = FetchType.LAZY)을 시도했지만 아무 소용이 없습니다. –