Saving value in Hibernate to another table than entity table - postgresql

Question

I have two tables bo_operator and hist_bo_operator_password. In bo_operator the id column is foreign key to hist_bo_operator_password and I can have many the same operator_id in hist_bo_operator_password and only one id in bo_operator.
My entity:
#Entity
#Table(name="bo_operator")
public class Operator implements Serializable
and that's how I am getting values from hist_bo_operator_password:
#ElementCollection
#CollectionTable(name="hist_bo_operator_password", joinColumns=#JoinColumn(name="id_operator"))
#Column(name="password")
public List<String> oldPasswords = new ArrayList<String>();
but when I'm trying to get only one value by:
#ElementCollection
#CollectionTable(name="hist_bo_operator_password", joinColumns=#JoinColumn(name="id_operator"))
#Column(name="password")
public String oldPassword;
I'm getting error:
org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'entityManagerFactory' defined in class path resource [org/springframework/boot/autoconfigure/orm/jpa/HibernateJpaAutoConfiguration.class]: Invocation of init method failed; nested exception is org.hibernate.AnnotationException: Illegal attempt to map a non collection as a #OneToMany, #ManyToMany or #CollectionOfElements: local.vlex.operator.model.Operator.oldPassword
and all I want to do is makeing an insert into hist_bo_operator_password by
operator.setOldPassword(oldPassword);. I think the problem is that it doesn't know which password take if there is many values for the same id.
How to achive it?
#Edit
I also tried:
#Table(name="bo_operator")
#SecondaryTable(name = "hist_bo_operator_password",pkJoinColumns=#PrimaryKeyJoinColumn(name="id_operator", referencedColumnName="id"))
I even found ORDER BY so:
#Column(name="password", table="hist_bo_operator_password")
#OrderBy("data_ins")
public String oldPassword;
but seems like there is no #Limit or something like this in JPA and I still have many values to the same id which cause error:
org.hibernate.HibernateException: Duplicate identifier in table for: [local.vlex.operator.model.Operator#1]

Answer 1

As you described at the first sentence you have one-to-many relationship
#ElementCollection
#CollectionTable(name="hist_bo_operator_password", joinColumns=#JoinColumn(name="id_operator"))
#Column(name="password")
#OrderBy("data_ins")
public List<String> oldPasswords = new ArrayList<String>();
Then add necessary getter
Optional<String> getPassword() {
return oldPasswords.size() > 0
? Optional.of(oldPasswords.get(0))
: Optional.empty();
}
And setter
void setPassword(String password) { // or maybe addPassword?
oldPasswords.add(password);
}

Answer 2

Why don't you create entity of hist_bo_operator_password?
Then you could have List of that entities (instead of just String List) and just add another object to List and save entity Operator.