Using logged in userid(foreign_key) for fillling out form in oneToMany mapping - spring

Question

I am working on spring-mvc application which uses Spring Security to login and hibernate as the ORM tool. So, my project only has 2 tables, Table Person has OneToMany mapping with Table Notes. So, once the user is logged into the system, he/she should be able to add notes, but while adding I would like to also save the Person's id, which is why I have used to OneToMany mapping. But I don't know how to get user's id and put it in the form. Below is my code.
The error is
org.postgresql.util.PSQLException: ERROR: null value in column "personid" violates not-null constraint
Which is understandable, thats why I want to know how I can retreive the personid.
Person model :
#Entity
#Table(name="person")
public class Person implements UserDetails{
private static final GrantedAuthority USER_AUTH = new SimpleGrantedAuthority("ROLE_USER");
#Id
#Column(name="personid")
#GeneratedValue(strategy = GenerationType.SEQUENCE,generator = "person_seq_gen")
#SequenceGenerator(name = "person_seq_gen",sequenceName = "person_seq")
private int id;
#OneToMany(mappedBy = "person1")
private Set<Notes> notes1;
}
Note model :
#Entity
#Table(name="note")
public class Notes {
#Id
#Column(name="noteid")
#GeneratedValue(strategy = GenerationType.SEQUENCE,generator = "note_gen")
#SequenceGenerator(name = "note_gen",sequenceName = "note_seq")
private int noteId;
#ManyToOne
#JoinColumn(name = "personid")
private Person person1;
}
SQL :
CREATE TABLE public.person (
personid INTEGER NOT NULL,
firstname VARCHAR,
username VARCHAR,
password VARCHAR,
CONSTRAINT id PRIMARY KEY (personid)
);
CREATE TABLE public.note (
noteid INTEGER NOT NULL,
sectionid INTEGER,
canvasid INTEGER,
text VARCHAR,
notecolor VARCHAR,
noteheadline VARCHAR,
personid INTEGER NOT NULL,
CONSTRAINT noteid PRIMARY KEY (noteid)
);
ALTER TABLE public.note ADD CONSTRAINT user_note_fk
FOREIGN KEY (personid)
REFERENCES public.person (personid)
ON DELETE NO ACTION
ON UPDATE NO ACTION
NOT DEFERRABLE;
Person controller :
#Controller
public class PersonController {
private PersonService personService;
#Autowired(required=true)
#Qualifier(value="personService")
public void setPersonService(PersonService ps){
this.personService = ps;
}
#RequestMapping(value = "/", method = RequestMethod.GET)
public String listPersons(Model model) {
model.addAttribute("person", new Person());
model.addAttribute("listPersons", this.personService.listPersons());
return "person";
}
//For add and update person both
#RequestMapping(value= "/person/add", method = RequestMethod.POST)
public String addPerson(#ModelAttribute("person") Person p){
//new person, add it
this.personService.addPerson(p);
return "redirect:/";
}
NoteController :
#Controller
public class NoteController {
private NotesService notesService;
#Autowired(required=true)
#Qualifier(value="notesService")
public void setNotesService(NotesService notesService){this.notesService=notesService;}
#RequestMapping(value = "/notes", method = RequestMethod.GET)
public String listNotes(Model model) {
model.addAttribute("notes", new Notes());
model.addAttribute("listnotes", this.notesService.listNotes());
return "notes";
}
#RequestMapping(value= "/note/add", method = RequestMethod.GET)
public String addNote(#ModelAttribute("notes") Notes p){
this.notesService.addNote(p);
return "redirect:/";
}
}
Note.jsp (here is where I add notes.)
<c:url var="addAction" value="/note/add" ></c:url>
<form:form action="${addAction}" commandName="notes">
<table>
<c:if test="${!empty notes.note}">
<tr>
<td>
<form:label path="noteid">
<spring:message text="noteid"/>
</form:label>
</td>
<td>
<form:input path="noteid" readonly="true" size="8" disabled="true" />
<form:hidden path="noteid" />
</td>
</tr>
</c:if>
<tr>
<td>
<form:label path="note">
<spring:message text="note"/>
</form:label>
</td>
<td>
<form:input path="note" />
</td>
</tr>
<tr>
<td>
<form:label path="notetag">
<spring:message text="notetag"/>
</form:label>
</td>
<td>
<form:input path="notetag" />
</td>
</tr>
<tr>
<td>
<form:label path="notecolor">
<spring:message text="notecolor"/>
</form:label>
</td>
<td>
<form:input path="notecolor" />
</td>
</tr>
<tr>
<td>
<form:label path="canvasid">
<spring:message text="canvasid"/>
</form:label>
</td>
<td>
<form:input path="canvasid" />
</td>
</tr>
<tr>
<td>
<form:label path="sectionid">
<spring:message text="sectionid"/>
</form:label>
</td>
<td>
<form:input path="sectionid" />
</td>
</tr>
<tr>
<td colspan="2">
<c:if test="${!empty notes.note}">
<input type="submit"
value="<spring:message text="Edit note"/>" />
</c:if>
<c:if test="${empty notes.note}">
<input type="submit"
value="<spring:message text="Add note"/>" />
</c:if>
</td>
</tr>
</table>
</form:form>

Answer 1

Not sure if I understood you correctly but when there is a logged in user (Principal) in a thread then you can just use SecurityContextHolder.getContext().getAuthentication().getPrincipal() to get the Principal or just inject it using #AuthenticationPrincipal or just make sure your Person implements Principal interface and inject it directly (I assume a Person is a User and a User is a Principal) to get the person.id.
In /note/add try like this:
public String addNote(#ModelAttribute("notes") Notes p, #AuthenticationPrincipal Person person)) {
p.setPerson1(person);
this.notesService.addNote(p);
return "redirect:/";
}
If you want to avoid setting it manually consider usage of AuditorAware and Auditable like here:
http://www.springbyexample.org/examples/spring-data-jpa-auditing-code-example.html