JPA won't save an entity correctly unless the references to other entities are set - jpa

Question

If I save this entity using JPA repository with a new defaultAssetId, it will only update the defaultAsssetId to the new value if I set defaultAsset as well. I want to be able to save without setting defaultAsset.
Same problem applies to taskType and assetRole.
package au.com.polonious.conf.entity;
import java.io.Serializable;
import java.util.Date;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.FetchType;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.JoinColumn;
import javax.persistence.ManyToOne;
import org.hibernate.annotations.Fetch;
import org.hibernate.annotations.FetchMode;
import org.hibernate.annotations.GenericGenerator;
import org.hibernate.annotations.Parameter;
#Entity
public class TaskTypeAssetRole implements Serializable {
#GenericGenerator(name="tasktypeassetroleidseq",
strategy = "org.hibernate.id.enhanced.SequenceStyleGenerator",
parameters = {
#Parameter(name = "sequence_name", value = "tasktypeassetroleidseq"),
#Parameter(name = "initial_value", value = "1"),
#Parameter(name = "increment_size", value = "1")
})
#Id
#GeneratedValue(generator = "tasktypeassetroleidseq")
private Long id;
#Column(insertable = false, updatable=false)
private Long taskTypeId;
#Fetch(FetchMode.JOIN)
#ManyToOne(fetch = FetchType.LAZY)
#JoinColumn(name="tasktypeid")
private TaskType taskType;
#Column(insertable = false, updatable=false)
private Long assetRoleId;
#Fetch(FetchMode.JOIN)
#ManyToOne(fetch = FetchType.LAZY)
#JoinColumn(name="assetRoleId")
private Role assetRole;
#Column(insertable = false, updatable=false)
private Long defaultAssetId;
#Fetch(FetchMode.JOIN)
#ManyToOne(fetch = FetchType.LAZY)
#JoinColumn(name="defaultassetid")
private Asset defaultAsset;
private Date startDate;
private Date endDate;
private String notes;
public Long getId() {
return id;
}
public void setId(Long id) {
this.id = id;
}
public Long getTaskTypeId() {
return taskTypeId;
}
public void setTaskTypeId(Long taskTypeId) {
this.taskTypeId = taskTypeId;
}
public TaskType getTaskType() {
return taskType;
}
public void setTaskType(TaskType taskType) {
this.taskType = taskType;
}
public Long getAssetRoleId() {
return assetRoleId;
}
public void setAssetRoleId(Long assetRoleId) {
this.assetRoleId = assetRoleId;
}
public Role getAssetRole() {
return assetRole;
}
public void setAssetRole(Role assetRole) {
this.assetRole = assetRole;
}
public Long getDefaultAssetId() {
return defaultAssetId;
}
public void setDefaultAssetId(Long defaultAssetId) {
this.defaultAssetId = defaultAssetId;
}
public Date getStartDate() {
return startDate;
}
public void setStartDate(Date startDate) {
this.startDate = startDate;
}
public Date getEndDate() {
return endDate;
}
public void setEndDate(Date endDate) {
this.endDate = endDate;
}
public String getNotes() {
return notes;
}
public void setNotes(String notes) {
this.notes = notes;
}
}
I tried saving a taskTypeAssetRole with a new defaultAssedId without setting defaultAsset and I expected the defaultAssedId for that entry in the database to be updated.
What ended up happening was defaultAssetId didn't change although everything else in the entry did update successfully and there were no errors.

Answer 1

Your mapping is inherently broken. The column defaultassetiId is mapped to two different values: the field defaultAssetId and to the id of defaultAsset.
You should remove the defaultAssetId because this construct might break on any update of your JPA provider.
You can use references instead of full entities to set the reference values without loading entities from the database. See https://docs.spring.io/spring-data/jpa/docs/current/api/org/springframework/data/jpa/repository/JpaRepository.html#getReferenceById-ID-
If you don't follow this advice you should remove updatable=false if you want to update a field.