Save an entity and all its related entities in a single save in spring boot

Question

I'm using Spring Boot,REST and JPA to build my application. In app, there are 2 entities with one to many relationship.

Entity 1 :

@Entity
@Table( name = "report")
@JsonIgnoreProperties(ignoreUnknown = true)
public class CustomReport {

@Id
@GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "REPORT_SEQ")
@SequenceGenerator(sequenceName = "REPORT_SEQ", allocationSize = 1, name = "REPORT_SEQ")
private Long id;

private String name;
private Long createdBy;
private Timestamp lastModifiedTimestamp;


@OneToMany(mappedBy = "customReport", cascade = CascadeType.ALL)
private Set<CustomReportActivity> customReportActivitySet;



public Set<CustomReportActivity> getCustomReportActivitySet() {
    return customReportActivitySet;
}

public void setCustomReportActivitySet(Set<CustomReportActivity> customReportActivitySet) {
    this.customReportActivitySet = customReportActivitySet;
}



public Long getId() {
    return id;
}

public void setId(Long id) {
    this.id = id;
}

public String getName() {
    return name;
}

public void setName(String name) {
    this.name = name;
}

public Long getCreatedBy() {
    return createdBy;
}

public void setCreatedBy(Long createdBy) {
    this.createdBy = createdBy;
}

public Timestamp getLastModifiedTimestamp() {
    return lastModifiedTimestamp;
}

public void setLastModifiedTimestamp(Timestamp lastModifiedTimestamp) {
    this.lastModifiedTimestamp = lastModifiedTimestamp;
}

}

Entity 2:

@Entity
@Table( name = "report_activity")
public class CustomReportActivity {

@Id
@GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "REPORT_ACTIVITY_SEQ")
@SequenceGenerator(sequenceName = "REPORT_ACTIVITY_SEQ", allocationSize = 1, name = "REPORT_ACTIVITY_SEQ")
private Long id;

String activityName;

@ManyToOne
@JoinColumn( name="report_id" )
@JsonBackReference
private CustomReport customReport;

public Long getId() {
    return id;
}

public void setId(Long id) {
    this.id = id;
}

public String getActivityName() {
    return activityName;
}

public void setActivityName(String activityName) {
    this.activityName = activityName;
}

public CustomReport getCustomReport() {
    return customReport;
}

public void setCustomReport(CustomReport customReport) {
    this.customReport = customReport;
}

}

And my request JSON is as follows :

{
   "name": "test report",
   "createdBy" : 129,
   "customReportActivitySet": [
        {"activityName":"a"},
        {"activityName":"b"},
        {"activityName":"c"},
        {"activityName":"d"},
        {"activityName":"e"}
    ]  
}

I want to save both entities in one shot. I've implemented the save functionality in following way:

@RequestMapping(value="/save", method = RequestMethod.POST)
public ResponseEntity<?> addReport(@RequestBody CustomReport customReport) {
    return new ResponseEntity<>(customReportService.createCustomReport(customReport), HttpStatus.CREATED);

}

CustomReportService method:

 public CustomReport createCustomReport(CustomReport customReport) {
    return customReportRepository.save(customReport);
}

CustomRepository:

public interface CustomReportRepository extends CrudRepository<CustomReport, Long> {

}

But I'm getting the constraint violation exception with this:

java.sql.SQLIntegrityConstraintViolationException: ORA-01400: cannot insert NULL into ("REPORT_ACTIVITY"."REPORT_ID")

Is it possible to save both entities in one save operation?

Please help!

Answer 1

You would have to add a small piece of code which would populate each CustomReportActivity within the CustomReport instance. Only then the persistence provide can successfully perform the cascade save operation:

public CustomReport createCustomReport(CustomReport customReport) {
   customReport.getCustomReportActivitySet.forEach((activity) -> {
      activity.setCustomReport(customReport);
   });

   return customReportRepository.save(customReport);
}

The bottom line is that the dependencies have to be set on both sides of the relationship.