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M:N table does not update

I have m:n relationship between User and Document. I am creating Document object, getting List - setDocumentsForUsers() and then I am persisting that object. Problem is, that document is created in my database, but not M:N relationship. What am I doing wrong? I tried to call flush after persisting, but it did not help at all.
#Entity
public class User {
#Id
#GeneratedValue(strategy = GenerationType.AUTO)
private long id;
#Column(name = "first_name")
private String firstName;
private String surname;
private String email;
private String password;
#ManyToMany
#JoinTable(
name = "users_roles",
joinColumns = #JoinColumn(
name = "user_id", referencedColumnName = "id"),
inverseJoinColumns = #JoinColumn(
name = "role_id", referencedColumnName = "id"))
private List<Role> roles;
#JsonIgnore
#ManyToMany
#JoinTable(
name="users_documents",
joinColumns = #JoinColumn(
name = "user_id", referencedColumnName = "id"),
inverseJoinColumns = #JoinColumn(
name="document_id", referencedColumnName = "id"))
private List<Document> usersDocuments;
#OneToMany(mappedBy="user")
private List<Document> sharedDocuments;
public User() {
}
public User(String firstName, String surname, String email, String password) {
this.firstName = firstName;
this.surname = surname;
this.email = email;
this.password = password;
}
public void setId(long id) {
this.id = id;
}
public long getId() {
return id;
}
public String getEmail() {
return email;
}
public void setEmail(String email){this.email = email;}
public String getPassword() {
return password;
}
public void setPassword(String password) {
this.password = password;
}
public void setRoles(List<Role> roles) {
this.roles = roles;
}
public String getFirstName() {
return firstName;
}
public void setFirstName(String firstName) {
this.firstName = firstName;
}
public String getSurname() {
return surname;
}
public void setSurname(String surname) {
this.surname = surname;
}
public List<Role> getRoles() {
return roles;
}
public List<Document> getUsersDocuments() {
return usersDocuments;
}
public void setUsersDocuments(List<Document> usersDocuments) {
this.usersDocuments = usersDocuments;
}
public List<Document> getSharedDocuments() {
return sharedDocuments;
}
public void setSharedDocuments(List<Document> sharedDocuments) {
this.sharedDocuments = sharedDocuments;
}
#Override
public boolean equals(Object o) {
if (this == o) return true;
if (!(o instanceof User)) return false;
User user = (User) o;
return getId() == user.getId();
}
#Override
public int hashCode() {
return Objects.hash(getId());
}
#Override
public String toString() {
return "User{" +
"firstName='" + firstName + '\'' +
", surname='" + surname + '\'' +
", email='" + email + '\'' +
", roles=" + roles +
'}';
}
}
My Document class:
#Entity
public class Document {
#Id
#GeneratedValue(strategy = GenerationType.AUTO)
private long id;
#Column(unique = true)
private String name;
private String title;
private String description;
#Column(name = "resource_path")
private String resourcePath;
#Column(name = "upload_datetime", columnDefinition = "DATETIME")
#Temporal(TemporalType.TIMESTAMP)
private Date uploadDatetime;
#ManyToMany(mappedBy = "usersDocuments")
private List<User> documentsForUsers;
#ManyToOne
#JoinColumn(name="user_id", nullable=false)
private User user;
public Document() {
}
public Document(String title, String description){
this.title = title;
this.description = description;
}
public long getId() {
return id;
}
public void setId(long id) {
this.id = id;
}
public String getTitle() {
return title;
}
public void setTitle(String title) {
this.title = title;
}
public String getDescription() {
return description;
}
public void setDescription(String description) {
this.description = description;
}
public String getResourcePath() {
return resourcePath;
}
public void setResourcePath(String resourcePath) {
this.resourcePath = resourcePath;
}
#Override
public String toString() {
return "Document{" +
"id=" + id +
", title='" + title + '\'' +
", description='" + description + '\'' +
", resourcePath='" + resourcePath + '\'' +
", uploadDatetime=" + uploadDatetime + '\'' +
". user=" + user;
}
#Override
public boolean equals(Object o) {
if (this == o) return true;
if (!(o instanceof Document)) return false;
Document document = (Document) o;
return getId() == document.getId();
}
#Override
public int hashCode() {
return Objects.hash(getId());
}
public Date getUploadDatetime() {
return uploadDatetime;
}
public void setUploadDatetime(Date uploadDatetime) {
// Date startDate = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss").parse(uploadDatetime.toString());
this.uploadDatetime = uploadDatetime;
}
public User getUser() {
return user;
}
public void setUser(User user) {
this.user = user;
}
public List<User> getDocumentsForUsers() {
return documentsForUsers;
}
public void setDocumentsForUsers(List<User> documentsForUsers) {
this.documentsForUsers = documentsForUsers;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
}
Perform this:
Optional<User> user = userService.getUserByEmail(createdBy);
Document document = new Document(title, desc);
document.setUploadDatetime(new Date());
document.setUser(user.get());
List<User> users = userService.getUsersByRoles(roles);
document.setDocumentsForUsers(users);
saveDocument(document);
#Override
public void saveDocument(Document document) {
entityManager.persist(document);
}

I think you need add the option to your #ManyToMany annotation: CascadeType.PERSIST.
By default, hibernate doesn't persists your relationship objects.
Try to use:
#ManyToMany(cascade = CascadeType.PERSIST)

Your class User is an Owner of relation #ManyToMany on
List<Document> usersDocuments;
as User has #JoinTable. Document class is an Inverse end.
If a Document is persisted then a data will be saved without relations. Because Inverse end cares only about itself but no relations.
By default you can persist a relation only from the owner side.
To be able to persist a relation from the inverse end then in your case as I tested:
In Document add cascade:
#ManyToMany(cascade = CascadeType.PERSIST, mappedBy = "usersDocuments")
private List<User> documentsForUsers;
and add a new code in your setter:
public void setDocumentsForUsers(List<User> documentsForUsers) {
if (documentsForUsers != null){
documentsForUsers.forEach(u -> {
u.getUsersDocuments().add(this); //here you should have not-null list u.getUsersDocuments()
});
}
this.documentsForUsers = documentsForUsers;
}
In User class add cascade:
#ManyToMany(cascade = CascadeType.PERSIST)
and
private List<Document> usersDocuments = new ArrayList<>();

Java Hot swap failed and schema change is not implemented

I work on a Java Spring boot app where I get the error of Hot-swap failed and schema change is not implemented and the operation is not supported by the VM. Afterward, the table is truncated and have no data at all.
I have 2 models provided below,
#Entity
public class User {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
private Long id;
#Column(name = "name")
#NotNull
#NotEmpty
private String name;
#Column(name = "countryName")
#NotNull
#NotEmpty
private String countryName;
#Column(name = "currencyName")
#NotNull
#NotEmpty
private String currencyName;
/*
* total steps is for the keepign the history of the user movement
* */
#Column(name = "totalSteps")
#Min(value = 0L, message = "The value must be positive")
private int totalSteps;
/*
* current steps is for providing the user reward. We will need to set
* it to zero after processing the user payment
* */
#Column(name = "currentSteps")
#Min(value = 0L, message = "The value must be positive")
private int currentSteps;
#OneToMany(mappedBy = "user", cascade = CascadeType.ALL, orphanRemoval = true)
private List<RewardList> rewardLists = new ArrayList<>();
public User() {
}
public User(#NotNull #NotEmpty String name, #NotNull #NotEmpty String countryName) {
this.name = name;
this.countryName = countryName;
}
public User(#NotNull #NotEmpty String name, #NotNull #NotEmpty String countryName, #Min(value = 0L, message = "The value must be positive") int totalSteps) {
this.name = name;
this.countryName = countryName;
this.totalSteps = totalSteps;
}
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 String getCountryName() {
return countryName;
}
public String getCurrencyName() {
return currencyName;
}
public void setCurrencyName(String currencyName) {
this.currencyName = currencyName;
}
public void setCountryName(String countryName) {
this.countryName = countryName;
}
public int getTotalSteps() {
return totalSteps;
}
public void setTotalSteps(int totalSteps) {
this.totalSteps = totalSteps;
}
public int getCurrentSteps() {
return currentSteps;
}
public void setCurrentSteps(int currentSteps) {
this.currentSteps = currentSteps;
}
public List<RewardList> getRewardLists() {
return rewardLists;
}
public void setRewardLists(RewardList rl) {
this.rewardLists.add(rl);
}
#Override
public boolean equals(Object o) {
if (this == o) return true;
if (!(o instanceof User)) return false;
User user = (User) o;
return getTotalSteps() == user.getTotalSteps() &&
getCurrentSteps() == user.getCurrentSteps() &&
getId().equals(user.getId()) &&
getName().equals(user.getName()) &&
getCountryName().equals(user.getCountryName()) &&
getRewardLists().equals(user.getRewardLists());
}
#Override
public int hashCode() {
return Objects.hash(getId(), getName(), getCountryName(), getTotalSteps(), getCurrentSteps(), getRewardLists());
}
#Override
public String toString() {
return "User{" +
"id=" + id +
", name='" + name + '\'' +
", countryName='" + countryName + '\'' +
", totalSteps=" + totalSteps +
", currentSteps=" + currentSteps +
'}';
}
}
#Entity
public class RewardList {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
private Long id;
#Column(name = "reward")
#Min(value = 0L, message = "The value must be positive")
private double reward;
#ManyToOne(fetch = FetchType.LAZY)
#JoinColumn(name = "user_id", nullable = false)
private User user;
public RewardList() {
}
public RewardList(User user) {
this.user = user;
}
public RewardList(#Min(value = 0L, message = "The value must be positive") double reward) {
this.reward = reward;
}
public Long getId() {
return id;
}
public void setId(Long id) {
this.id = id;
}
public double getReward() {
return reward;
}
public void setReward(double reward) {
this.reward = reward;
}
public User getUser() {
return user;
}
public void setUser(User user) {
this.user = user;
}
#Override
public boolean equals(Object o) {
if (this == o) return true;
if (!(o instanceof RewardList)) return false;
RewardList list = (RewardList) o;
return Double.compare(list.getReward(), getReward()) == 0 &&
getId().equals(list.getId()) &&
getUser().equals(list.getUser());
}
#Override
public int hashCode() {
return Objects.hash(getId(), getReward(), getUser());
}
#Override
public String toString() {
return "RewardList{" +
"id=" + id +
", reward=" + reward +
", user=" + user +
'}';
}
}
The end-point where I have this issue provided below,
// $ curl -X PUT http://localhost:8080/api/v1/users/calculateReward?userId=1 | jq
#PutMapping("/calculateReward")
public ResponseEntity<Object> calculateReward(#RequestParam("userId") Long userId) {
Optional<User> optional = userService.findById(userId);
if (!optional.isPresent()) {
return ResponseEntity.status(HttpStatus.NO_CONTENT).build();
}
User user = optional.get();
double reward = user.getCurrentSteps() * Parameters.REWARD_PER_STEPS_EUR;
RewardList list = new RewardList();
list.setUser(user);
list.setReward(reward);
rewardListService.save(list);
user.setCurrentSteps(0);
user.setRewardLists(list);
userService.save(user);
JSONObject json = new JSONObject();
double convertionRateToEuro = currencyMap.get(user.getCurrencyName());
double rewardConverted = reward * convertionRateToEuro;
json.put("name", user.getName());
json.put("currency", user.getCurrencyName());
json.put("reward", rewardConverted);
return ResponseEntity.status(HttpStatus.CREATED).body(json);
}
Does anyone know what is going on and can provide a solution?
Thank you.

I find the reason and below I provide a solution. We will need to save the models based on the hierarchy. HotSwap doesn't support adding methods or hierarchy changes as indicated by the error messages. It's the limitation of Java HotSwap, not IntelliJ IDEA. The proper way of code sequence will be,
User user = optional.get();
RewardList list = new RewardList();
list.setUser(user);
list.setReward(reward);
user.setCurrentSteps(0);
user.setRewardLists(list);
// first save the User
userService.save(user);
// Then, save the RewardList as it has one to many relations
rewardListService.save(list);

OneToMany relationship error: Field 'XX' doesn't have a default value

I'm trying to create One-To-Many relationship between two objects but I got this error. I don't know how to mapping property ID from object MyUserAccount to object Book. ID is a String data received from Google (I'm doing Social Login in my project).
Error
PreparedStatementCallback; SQL [INSERT INTO Books(TENSACH, TACGIA, NHANXET, TINHTRANG, THELOAI, IMAGE, IMAGE_NAME) VALUES ( ?, ?, ?, ?, ?, ?, ?)]; Field 'ID' doesn't have a default value; nested exception is java.sql.SQLException: Field 'ID' doesn't have a default value
BookDao (How I save object Book into database)
public void save(Book book) {
// TODO Auto-generated method stub
KeyHolder keyHolder = new GeneratedKeyHolder();
String sql = "INSERT INTO Books(TENSACH, TACGIA, NHANXET, TINHTRANG, THELOAI, IMAGE, IMAGE_NAME) "
+ "VALUES ( :tensach, :tacgia, :nhanxet, :tinhtrang, :theloai, :image, :image_name)";
namedParameterJdbcTemplate.update(sql, getSqlParameterByModel(book), keyHolder);
book.setBook_ID(keyHolder.getKey().intValue());
}
private SqlParameterSource getSqlParameterByModel(Book book) {
MapSqlParameterSource paramSource = new MapSqlParameterSource();
paramSource.addValue("book_id", book.getBook_ID());
paramSource.addValue("tensach", book.getTensach());
paramSource.addValue("tacgia", book.getTacgia());
paramSource.addValue("nhanxet", book.getNhanxet());
paramSource.addValue("tinhtrang", book.getTinhtrang());
paramSource.addValue("image", book.getImage());
paramSource.addValue("image_name", book.getImage_name());
paramSource.addValue("theloai", book.getTheloai());
return paramSource;
}
Model Book
public class Book implements Serializable {
private static final long serialVersionUID = 1L;
private Integer book_ID;
private String tensach;
private String tacgia;
private String nhanxet;
private String tinhtrang;
private String theloai;
private byte[] image;
private String image_name;
private String data;
private MyUserAccount myUserAccount;
public Book() {
}
#ManyToOne(fetch = FetchType.LAZY)
#JoinColumn(name = "ID", nullable = false)
public MyUserAccount getMyUserAccount() {
return this.myUserAccount;
}
public void setMyUserAccount(MyUserAccount myUserAccount) {
this.myUserAccount = myUserAccount;
}
#Id
#GeneratedValue(strategy = IDENTITY)
#Column(name = "book_id", unique = true, nullable = false)
public Integer getBook_ID() {
return book_ID;
}
#Column(name = "image_name")
public String getImage_name() {
return image_name;
}
#Column(name = "tensach", length = 50, nullable = true)
public String getTensach() {
return tensach;
}
#Lob
#Type(type = "org.hibernate.type.BinaryType")
#Column(name = "image", columnDefinition = "LONGBLOB", nullable = true)
public byte[] getImage() {
return image;
}
#Column(name = "tacgia", length = 50, nullable = true)
public String getTacgia() {
return tacgia;
}
#Column(name = "nhanxet", length = 100, nullable = true)
public String getNhanxet() {
return nhanxet;
}
#Column(name = "tinhtrang", length = 50, nullable = true)
public String getTinhtrang() {
return tinhtrang;
}
#Column(name = "theloai", length = 50, nullable = true)
public String getTheloai() {
return theloai;
}
#Column(name = "data", length = 16777215)
public String getData() {
return data;
}
public void setBook_ID(Integer book_ID) {
this.book_ID = book_ID;
}
public void setImage_name(String image_name) {
this.image_name = image_name;
}
public void setImage(byte[] image) {
this.image = image;
}
public void setTensach(String tensach) {
this.tensach = tensach;
}
public void setTacgia(String tacgia) {
this.tacgia = tacgia;
}
public void setNhanxet(String nhanxet) {
this.nhanxet = nhanxet;
}
public void setTinhtrang(String tinhtrang) {
this.tinhtrang = tinhtrang;
}
public void setTheloai(String theloai) {
this.theloai = theloai;
}
public void setData(String data) {
this.data = data;
}
#Override
public String toString() {
return "Book [book_ID=" + book_ID + ", tensach=" + tensach + ", tacgia=" + tacgia + ", nhanxet=" + nhanxet
+ ", tinhtrang=" + tinhtrang + ", theloai=" + theloai + ", image=" + Arrays.toString(image) + "]";
}
}
Model MyUserAccount.
public class MyUserAccount implements Serializable {
private static final long serialVersionUID = 1L;
public static final String ROLE_USER = "ROLE_USER";
private String id;
private String email;
private String userName;
private String firstName;
private String lastName;
private String password;
private String role;
private String enabled;
private List<Book> book = new ArrayList<Book>(0);
public MyUserAccount() {
}
#OneToMany(fetch = FetchType.LAZY, mappedBy = "myUserAccount")
public List<Book> getBook() {
return book;
}
public void setBook(List<Book> book) {
this.book = book;
}
public MyUserAccount(String id, String email, String userName, String firstName, //
String lastName, String password, String role, String enabled) {
this.id = id;
this.email = email;
this.userName = userName;
this.firstName = firstName;
this.lastName = lastName;
this.password = password;
this.role = role;
this.enabled = enabled;
}
#Id
#Column(name = "ID", unique = true, nullable = false)
public String getId() {
return id;
}
public void setId(String id) {
this.id = id;
}
#Column(name = "EMAIL", unique = true, nullable = false)
public String getEmail() {
return email;
}
public void setEmail(String email) {
this.email = email;
}
#Column(name = "USER_NAME", unique = true, nullable = false)
public String getUserName() {
return userName;
}
public void setUserName(String userName) {
this.userName = userName;
}
#Column(name = "FIRST_NAME", nullable = false)
public String getFirstName() {
return firstName;
}
public void setFirstName(String firstName) {
this.firstName = firstName;
}
#Column(name = "LAST_NAME", nullable = false)
public String getLastName() {
return lastName;
}
public void setLastName(String lastName) {
this.lastName = lastName;
}
#Column(name = "PASSWORD", nullable = false)
public String getPassword() {
return password;
}
public void setPassword(String password) {
this.password = password;
}
#Column(name = "ROLE", nullable = false)
public String getRole() {
return role;
}
public void setRole(String role) {
this.role = role;
}
#Column(name = "ENABLED", columnDefinition = "VARCHAR(1) default 'Y'", nullable = false)
public String getEnabled() {
return enabled;
}
public void setEnabled(String enabled) {
this.enabled = enabled;
}
}
Controller
#RequestMapping(value = "/motsach/add/", method = RequestMethod.POST)
public String saveBook(#ModelAttribute("bookForm") #Validated Book book, BindingResult result, Model model,
#RequestParam CommonsMultipartFile[] image, String userName, final RedirectAttributes redirectAttributes)
throws IOException, UnsupportedEncodingException {
MyUserAccount myUserAccount = myUserAccountDAO.findByUserName(userName);
System.out.println(userName + "sssssssssssss");
book.setMyUserAccount(myUserAccount);
redirectAttributes.addFlashAttribute("css", "success");
if (book.getBook_ID() == null) {
System.out.println(book.getBook_ID());
redirectAttributes.addFlashAttribute("msg", "book added successfully!");
} else {
redirectAttributes.addFlashAttribute("msg", "book updated successfully!");
}
for (CommonsMultipartFile aFile : image) {
System.out.println("Saving file: " + aFile.getOriginalFilename());
book.setImage_name(aFile.getOriginalFilename());
book.setImage(aFile.getBytes());
System.out.println("Damn that Shit!");
}
bookService.saveOrUpdate(book);
// POST/REDIRECT/GET
return "redirect:/motsach/" + book.getBook_ID();
}

You have a #manyToOne (with ID as name ) relation that can't be null. So in order to add a book you have to set MyUserAccount to a book before saving or you can turn into :
#ManyToOne(fetch = FetchType.LAZY)
#JoinColumn(name = "ID", nullable = true)
public MyUserAccount getMyUserAccount() {
return this.myUserAccount;
}
and modify your column in your database to set the possibility of null value.

Hibernate mappedBy and ManyToMany

I'm starting from scratch a new project and i got this problem which i cannot solve. I have three entities, and they all have a manytomany relationship with each other. There is the Cluster:
#Entity
#Component
#Table(name = "clusterEntity")
public class Cluster {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
#Column(name = "id", nullable = false, updatable = false)
private Long id;
#Column(name = "name")
private String name;
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;
}
#ManyToMany
#JoinTable(name="cluster_user",
joinColumns=#JoinColumn(name="cluster_id", referencedColumnName="id"),
inverseJoinColumns=#JoinColumn(name="user_id", referencedColumnName="id"))
private List<User> users_cluster;
#ManyToMany
#JoinTable(name="cluster_sito",
joinColumns=#JoinColumn(name="cluster_id", referencedColumnName="id"),
inverseJoinColumns=#JoinColumn(name="sito_id", referencedColumnName="id"))
private List<Sito> sitos;
#Override
public String toString() {
return "Cluster{" +
"id=" + id +
", name='" + name +
", users='" + users_cluster.toString() +
'}';
}
}
This is the User:
#Entity
#Component
#Table(name = "userEntity")
public class User {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
#Column(name = "id", nullable = false, updatable = false)
private Long id;
#Column(name = "email", nullable = false, unique = true)
private String email;
#Column(name = "password_hash", nullable = false)
private String passwordHash;
#Column(name = "role", nullable = false)
#Enumerated(EnumType.STRING)
private Role role;
#Column(name = "G1", nullable = true)
private String G1;
#Column(name = "G2", nullable = true)
private String G2;
#Column(name = "G3", nullable = true)
private String G3;
#Column(name = "G4", nullable = true)
private String G4;
#Column(name = "G5", nullable = true)
private String G5;
#Column(name = "G6", nullable = true)
private String G6;
#Column (name = "access_token", nullable = true)
private String access_token;
#Column (name = "refresh_token", nullable = true)
private String refresh_token;
public Long getId() {
return id;
}
public String getEmail() {
return email;
}
public void setEmail(String email) {
this.email = email;
}
public String getPasswordHash() {
return passwordHash;
}
public void setPasswordHash(String passwordHash) {
this.passwordHash = passwordHash;
}
public Role getRole() {
return role;
}
public void setRole(Role role) {
this.role = role;
}
public String getG1() {
return G1;
}
public void setG1(String g1) {
G1 = g1;
}
public String getG2() {
return G2;
}
public void setG2(String g2) {
G2 = g2;
}
public String getG3() {
return G3;
}
public void setG3(String g3) {
G3 = g3;
}
public String getG4() {
return G4;
}
public void setG4(String g4) {
G4 = g4;
}
public String getG5() {
return G5;
}
public void setG5(String g5) {
G5 = g5;
}
public String getG6() {
return G6;
}
public void setG6(String g6) {
G6 = g6;
}
public String getAccess_token() {
return access_token;
}
public void setAccess_token(String access_token) {
this.access_token = access_token;
}
public String getRefresh_token() {
return refresh_token;
}
public void setRefresh_token(String refresh_token) {
this.refresh_token = refresh_token;
}
#ManyToMany(mappedBy="users_cluster")
private List<User> users_cluster;
#ManyToMany(mappedBy="users_sito")
private List<User> users_sito;
public User(){}
#Override
public String toString() {
return "User{" +
"id=" + id +
", email='" + email.replaceFirst("#.*", "#***") +
", passwordHash='" + passwordHash.substring(0, 10) +
", role=" + role +
'}';
}
}
This is the Sito:
#Entity
#Component
#Table(name = "sitoEntity")
public class Sito {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
#Column(name = "id", nullable = false, updatable = false)
private Long id;
#Column(name = "name")
private String name;
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;
}
#ManyToMany
#JoinTable(name="sito_user",
joinColumns=#JoinColumn(name="sito_id", referencedColumnName="id"),
inverseJoinColumns=#JoinColumn(name="user_id", referencedColumnName="id"))
private List<User> users_sito;
#Override
public String toString() {
return "Sito{" +
"id=" + id +
", name='" + name+
", users='" + users_sito.toString()+
'}';
}
}
When i try compiling with maven i get the following error about mappedBY, as if it was written on both side of the relation, but in fact it is written only on one side:
Caused by: org.hibernate.AnnotationException: Illegal use of mappedBy on both sides of the relationship: User.users_cluster
Anyone has any ideaof what am i doing wrong?

Clustor
As far as I can see the Cluster entity is annotated correctly except some kine of naming convention. Instead of
private List<User> users_cluster;
I would recommend using
private List<User> users;
The list contains users so it should be named to reflect that; good naming is the best documentation, (imo).
User
This entity seems to be correctly annotated but the references are wrong as they are self referencing. So the entity should be modified as follows if you want to create a many-to-many relationship between the thre entities:
public class User {
// ...
#ManyToMany(mappedBy="users")
private List<Cluster> clusters;
#ManyToMany(mappedBy="users")
private List<Sito> sitos;
// getters + setters
}
Sito
Here too I made a small modification as follows:
public class Sito {
// ...
#ManyToMany
#JoinTable(name="sito_user",
joinColumns=#JoinColumn(name="sito_id", referencedColumnName="id"),
inverseJoinColumns=#JoinColumn(name="user_id", referencedColumnName="id"))
private List<User> users;
#ManyToMany(mappedBy = "sitos")
private List<Cluster> clusters;
// getters + setters
}
Now your three entities should be related to each other as you desired.

Persisting OneToMany relationship only persists first object in set?

Been messing around with Hibernate and PostgreSQL trying to get it to work as expected.
But for some reason when I try to persist an object with a #OneToMany relationship with more than one item in the set all but the first item seem to be ignored. I've tried this via local and remote interfaces but get the same results each time. No exceptions are thrown, it looks like hibernate just stops persisting after the first unit has been persisted.
Any help much appreciated this one has been eluding me for days now.
I'm using Hibernate 3.5 and PostgreSQL 8.4.4 with Glassfish v3. All the annotations in the source are from the package javax.persistence - had to remove imports because of the character limit.
The FacadeManager is simply a utility to take the hassle out of jndi lookups, it simplifies accessing remote facades.
Here is the test method
#Test
public void testOneToManyCascade() throws Exception {
/*
* Set up entities requred to perform the test
*/
UnitFacadeRemote unitfr = FacadeManager
.getFacade(UnitFacadeRemote.class);
UserFacadeRemote userfr = FacadeManager
.getFacade(UserFacadeRemote.class);
User user = new User("P", "P", "000000", true, new Date(), "ypy#ypy",
"wordof mout", "slacker", "password");
Address address = new Address("yo", "go", "YOKO", "4123");
address.setCountry(FacadeManager.getFacade(CountryFacadeRemote.class)
.find(2));
user.setAddress(address);
Unit unit1 = new Unit(1, "Test Unit1", new Date(), "DisService",
"MyNation");
Unit unit2 = new Unit(2, "Test Unit2", new Date(), "DisService",
"TheirNation");
Unit unit3 = new Unit(3, "Test Unit3", new Date(), "DisService",
"TheirNation");
// Check no game exists
assertThat(FacadeManager.getFacade(GameFacadeRemote.class).findAll()
.size(), is(0));
Game game = new Game("blabla", 3333, "A game!", true);
// Create game and return reference to persisted game instance
game = FacadeManager.getFacade(GameFacadeRemote.class).registerGame(
game);
unit1.setGame(game);
unit2.setGame(game);
unit3.setGame(game);
// Find a virtue
Virtue v = FacadeManager.getFacade(VirtueFacadeRemote.class).find(1);
unit1.setVirtue(v);
unit2.setVirtue(v);
unit3.setVirtue(v);
// check that none of the above exist already
assertThat(userfr.findAll().size(), is(0));
assertThat(unitfr.findAll().size(), is(0));
/*
* Try persisting the by cascading from the user
*/
Set<Unit> unitSet = new HashSet<Unit>();
unitSet.add(unit2);
unitSet.add(unit1);
unitSet.add(unit3);
user.setUnitSet(unitSet);
unit1.setUser(user);
unit2.setUser(user);
unit3.setUser(user);
// Persist
userfr.create(user);
/*
* The result of the preceding persist is that the game, user, address
* and one unit are persisted, in this case unit2 but it seems whichever
* unit is first added to unitSet is the one that is persisted.
*/
}
Here follow the various entity classes
package com.game.database.entity;
#Entity
#Table(name = "address")
#NamedQueries({
#NamedQuery(name = "Address.findAll", query = "SELECT a FROM Address a"),
#NamedQuery(name = "Address.findById", query = "SELECT a FROM Address a WHERE a.id = :id"),
#NamedQuery(name = "Address.findByLine1", query = "SELECT a FROM Address a WHERE a.line1 = :line1"),
#NamedQuery(name = "Address.findByLine2", query = "SELECT a FROM Address a WHERE a.line2 = :line2"),
#NamedQuery(name = "Address.findByCity", query = "SELECT a FROM Address a WHERE a.city = :city"),
#NamedQuery(name = "Address.findByAreaCode", query = "SELECT a FROM Address a WHERE a.areaCode = :areaCode") })
public class Address implements Serializable {
private static final long serialVersionUID = 1L;
#SequenceGenerator(name = "address_id_seq", sequenceName = "address_id_seq", allocationSize = 1)
#Id
#GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "address_id_seq")
#Basic(optional = false)
#Column(name = "id")
private Integer id;
#Basic(optional = false)
#Column(name = "line1")
private String line1;
#Basic(optional = false)
#Column(name = "line2")
private String line2;
#Basic(optional = false)
#Column(name = "city")
private String city;
#Basic(optional = false)
#Column(name = "areaCode")
private String areaCode;
#JoinColumn(name = "country", referencedColumnName = "id")
#ManyToOne(optional = false)
private Country country;
#OneToMany(cascade = CascadeType.ALL, mappedBy = "address")
private Set<User> userSet;
#OneToMany(cascade = CascadeType.ALL, mappedBy = "address")
private Set<CardDetails> cardDetailsSet;
public Address() {
}
public Address(Integer id) {
this.id = id;
}
public Address(String line1, String line2, String city, String areaCode) {
this.line1 = line1;
this.line2 = line2;
this.city = city;
this.areaCode = areaCode;
}
public Integer getId() {
return id;
}
public void setId(Integer id) {
this.id = id;
}
public String getLine1() {
return line1;
}
public void setLine1(String line1) {
this.line1 = line1;
}
public String getLine2() {
return line2;
}
public void setLine2(String line2) {
this.line2 = line2;
}
public String getCity() {
return city;
}
public void setCity(String city) {
this.city = city;
}
public String getAreaCode() {
return areaCode;
}
public void setAreaCode(String areaCode) {
this.areaCode = areaCode;
}
public Country getCountry() {
return country;
}
public void setCountry(Country country) {
this.country = country;
}
public Set<User> getUserSet() {
return userSet;
}
public void setUserSet(Set<User> userSet) {
this.userSet = userSet;
}
public Set<CardDetails> getCardDetailsSet() {
return cardDetailsSet;
}
public void setCardDetailsSet(Set<CardDetails> cardDetailsSet) {
this.cardDetailsSet = cardDetailsSet;
}
#Override
public int hashCode() {
int hash = 0;
hash += (id != null ? id.hashCode() : 0);
return hash;
}
#Override
public boolean equals(Object object) {
// TODO: Warning - this method won't work in the case the id fields are
// not set
if (!(object instanceof Address)) {
return false;
}
Address other = (Address) object;
if ((this.id == null && other.id != null)
|| (this.id != null && !this.id.equals(other.id))) {
return false;
}
return true;
}
#Override
public String toString() {
return "com.game.database.entity.Address[id=" + id + "]";
}
}
--
package com.game.database.entity;
#Entity
#Table(name = "game")
#NamedQueries({
#NamedQuery(name = "Game.findAll", query = "SELECT g FROM Game g"),
#NamedQuery(name = "Game.findById", query = "SELECT g FROM Game g WHERE g.id = :id"),
#NamedQuery(name = "Game.findByHost", query = "SELECT g FROM Game g WHERE g.host = :host"),
#NamedQuery(name = "Game.findByPort", query = "SELECT g FROM Game g WHERE g.port = :port"),
#NamedQuery(name = "Game.findByDescription", query = "SELECT g FROM Game g WHERE g.description = :description"),
#NamedQuery(name = "Game.findByActive", query = "SELECT g FROM Game g WHERE g.active = :active"),
#NamedQuery(name = "Game.findByHostAndPort", query = "SELECT g FROM Game g WHERE g.host = :host AND g.port = :port") })
public class Game implements Serializable {
private static final long serialVersionUID = 1L;
#SequenceGenerator(name = "game_id_seq", sequenceName = "game_id_seq", allocationSize = 1)
#Id
#GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "game_id_seq")
#Basic(optional = false)
#Column(name = "id")
private Integer id;
#Basic(optional = false)
#Column(name = "host")
private String host;
#Basic(optional = false)
#Column(name = "port")
private int port;
#Basic(optional = false)
#Column(name = "description")
private String description;
#Basic(optional = false)
#Column(name = "active")
private Boolean active;
#OneToMany(cascade = CascadeType.ALL, mappedBy = "game")
private Set<Unit> unitSet;
#OneToMany(cascade = CascadeType.ALL, mappedBy = "game")
private Set<Payment> paymentSet;
public Game() {
}
public Game(Integer id) {
this.id = id;
}
public Game(String host, int port, String description, Boolean active) {
this.host = host;
this.port = port;
this.description = description;
this.active = active;
}
public Integer getId() {
return id;
}
public void setId(Integer id) {
this.id = id;
}
public String getHost() {
return host;
}
public void setHost(String host) {
this.host = host;
}
public int getPort() {
return port;
}
public void setPort(int port) {
this.port = port;
}
public String getDescription() {
return description;
}
public void setDescription(String description) {
this.description = description;
}
public Boolean getActive() {
return active;
}
public void setActive(Boolean active) {
this.active = active;
}
public Set<Unit> getUnitSet() {
return unitSet;
}
public void setUnitSet(Set<Unit> unitSet) {
this.unitSet = unitSet;
}
public Set<Payment> getPaymentSet() {
return paymentSet;
}
public void setPaymentSet(Set<Payment> paymentSet) {
this.paymentSet = paymentSet;
}
#Override
public int hashCode() {
int hash = 0;
hash += (id != null ? id.hashCode() : 0);
return hash;
}
#Override
public boolean equals(Object object) {
// TODO: Warning - this method won't work in the case the id fields are
// not set
if (!(object instanceof Game)) {
return false;
}
Game other = (Game) object;
if ((this.id == null && other.id != null)
|| (this.id != null && !this.id.equals(other.id))) {
return false;
}
return true;
}
#Override
public String toString() {
return "com.game.database.entity.Game[id=" + id + "]";
}
}
--
package com.game.database.entity;
#Entity
#Table(name = "unit")
#NamedQueries({
#NamedQuery(name = "Unit.findAll", query = "SELECT u FROM Unit u"),
#NamedQuery(name = "Unit.findById", query = "SELECT u FROM Unit u WHERE u.id = :id"),
#NamedQuery(name = "Unit.findByUnitId", query = "SELECT u FROM Unit u WHERE u.unitId = :unitId"),
#NamedQuery(name = "Unit.findByName", query = "SELECT u FROM Unit u WHERE u.name = :name"),
#NamedQuery(name = "Unit.findByRegistrationDate", query = "SELECT u FROM Unit u WHERE u.registrationDate = :registrationDate"),
#NamedQuery(name = "Unit.findByService", query = "SELECT u FROM Unit u WHERE u.service = :service"),
#NamedQuery(name = "Unit.findByNation", query = "SELECT u FROM Unit u WHERE u.nation = :nation") })
public class Unit implements Serializable {
private static final long serialVersionUID = 1L;
#SequenceGenerator(name = "unit_id_seq", sequenceName = "unit_id_seq", allocationSize = 1)
#Id
#GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "unit_id_seq")
#Basic(optional = false)
#Column(name = "id")
private Integer id;
#Basic(optional = false)
#Column(name = "unitId")
private Integer unitId;
#Basic(optional = false)
#Column(name = "name")
private String name;
#Basic(optional = false)
#Column(name = "registrationDate")
#Temporal(TemporalType.TIMESTAMP)
private Date registrationDate;
#Basic(optional = false)
#Column(name = "service")
private String service;
#Basic(optional = false)
#Column(name = "nation")
private String nation;
#JoinColumn(name = "virtue", referencedColumnName = "id")
#ManyToOne(optional = false)
private Virtue virtue;
#JoinColumn(name = "customer", referencedColumnName = "id")
#ManyToOne(optional = false)
private User customer;
#JoinColumn(name = "game", referencedColumnName = "id")
#ManyToOne(optional = false)
private Game game;
public Unit() {
}
public Unit(Integer id) {
this.id = id;
}
public Unit(Integer unitId, String name, Date registrationDate,
String service, String nation) {
this.unitId = unitId;
this.name = name;
this.registrationDate = registrationDate;
this.service = service;
this.nation = nation;
}
public Integer getId() {
return id;
}
public void setId(Integer id) {
this.id = id;
}
public Integer getUnitId() {
return unitId;
}
public void setUnitId(Integer unitId) {
this.unitId = unitId;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public Date getRegistrationDate() {
return registrationDate;
}
public void setRegistrationDate(Date registrationDate) {
this.registrationDate = registrationDate;
}
public String getService() {
return service;
}
public void setService(String service) {
this.service = service;
}
public String getNation() {
return nation;
}
public void setNation(String nation) {
this.nation = nation;
}
public Virtue getVirtue() {
return virtue;
}
public void setVirtue(Virtue virtue) {
this.virtue = virtue;
}
public User getUser() {
return customer;
}
public void setUser(User user) {
this.customer = user;
}
public Game getGame() {
return game;
}
public void setGame(Game game) {
Logger.getLogger("org.hibernate").setLevel(Level.FINEST);
this.game = game;
}
#Override
public int hashCode() {
int hash = 0;
hash += (id != null ? id.hashCode() : 0);
return hash;
}
#Override
public boolean equals(Object object) {
// TODO: Warning - this method won't work in the case the id fields are
// not set
if (!(object instanceof Unit)) {
return false;
}
Unit other = (Unit) object;
if ((this.id == null && other.id != null)
|| (this.id != null && !this.id.equals(other.id))) {
return false;
}
return true;
}
#Override
public String toString() {
return "com.game.database.entity.Unit[id=" + id + "]";
}
#Transient
private String command;
/**
* Get the value of command
*
* #return the value of command
*/
public String getCommand() {
return command;
}
/**
* Set the value of command
*
* #param command
* new value of command
*/
public void setCommand(String command) {
this.command = command;
}
#Transient
private String rank;
/**
* Get the value of rank
*
* #return the value of rank
*/
public String getRank() {
return rank;
}
/**
* Set the value of rank
*
* #param rank
* new value of rank
*/
public void setRank(String rank) {
this.rank = rank;
}
#Transient
private BigDecimal price;
/**
* Get the value of price
*
* #return the value of price
*/
public BigDecimal getPrice() {
return price;
}
/**
* Set the value of price
*
* #param price
* new value of price
*/
public void setPrice(BigDecimal price) {
this.price = price;
}
}
--
package com.game.database.entity;
#Entity
#Table(name = "customer")
#NamedQueries({
#NamedQuery(name = "User.findAll", query = "SELECT u FROM User u"),
#NamedQuery(name = "User.findById", query = "SELECT u FROM User u WHERE u.id = :id"),
#NamedQuery(name = "User.findByGivenName", query = "SELECT u FROM User u WHERE u.givenName = :givenName"),
#NamedQuery(name = "User.findBySurname", query = "SELECT u FROM User u WHERE u.surname = :surname"),
#NamedQuery(name = "User.findByPhoneNumber", query = "SELECT u FROM User u WHERE u.phoneNumber = :phoneNumber"),
#NamedQuery(name = "User.findBySex", query = "SELECT u FROM User u WHERE u.sex = :sex"),
#NamedQuery(name = "User.findByBirthYear", query = "SELECT u FROM User u WHERE u.birthYear = :birthYear"),
#NamedQuery(name = "User.findByEmail", query = "SELECT u FROM User u WHERE u.email = :email"),
#NamedQuery(name = "User.findByInfoSource", query = "SELECT u FROM User u WHERE u.infoSource = :infoSource"),
#NamedQuery(name = "User.findByOccupation", query = "SELECT u FROM User u WHERE u.occupation = :occupation"),
#NamedQuery(name = "User.findByPassword", query = "SELECT u FROM User u WHERE u.password = :password"),
#NamedQuery(name = "User.findByEmailAndPassword", query = "SELECT u FROM User u WHERE u.password = :password AND u.email = :email") })
public class User implements Serializable {
private static final long serialVersionUID = 1L;
#SequenceGenerator(name = "user_id_seq", sequenceName = "user_id_seq", allocationSize = 1)
#Id
#GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "user_id_seq")
#Basic(optional = false)
#Column(name = "id")
private Integer id;
#Basic(optional = false)
#Column(name = "givenName")
private String givenName;
#Basic(optional = false)
#Column(name = "surname")
private String surname;
#Basic(optional = false)
#Column(name = "phoneNumber")
private String phoneNumber;
#Basic(optional = false)
#Column(name = "sex")
private boolean sex;
#Basic(optional = false)
#Column(name = "birthYear")
#Temporal(TemporalType.DATE)
private Date birthYear;
#Basic(optional = false)
#Column(name = "email")
private String email;
#Basic(optional = false)
#Column(name = "infoSource")
private String infoSource;
#Basic(optional = false)
#Column(name = "occupation")
private String occupation;
#Basic(optional = false)
#Column(name = "password")
private String password;
/**
* The EAGER fetch type ensures that when we get access a unit remotely it
* has had its unit set initialised and populated
*/
#OneToMany(cascade = CascadeType.ALL, mappedBy = "customer", fetch = FetchType.EAGER)
private Set<Unit> unitSet;
#OneToMany(cascade = CascadeType.ALL, mappedBy = "customer", fetch = FetchType.EAGER)
private Set<Payment> paymentSet;
#JoinColumn(name = "address", referencedColumnName = "id")
#ManyToOne(cascade = CascadeType.ALL, optional = false)
private Address address;
public User() {
}
public User(Integer id) {
this.id = id;
}
public User(String givenName, String surname, String phoneNumber,
boolean sex, Date birthYear, String email, String infoSource,
String occupation, String password) {
this.givenName = givenName;
this.surname = surname;
this.phoneNumber = phoneNumber;
this.sex = sex;
this.birthYear = birthYear;
this.email = email;
this.infoSource = infoSource;
this.occupation = occupation;
this.password = password;
}
public Integer getId() {
return id;
}
public void setId(Integer id) {
this.id = id;
}
public String getGivenName() {
return givenName;
}
public void setGivenName(String givenName) {
this.givenName = givenName;
}
public String getSurname() {
return surname;
}
public void setSurname(String surname) {
this.surname = surname;
}
public String getPhoneNumber() {
return phoneNumber;
}
public void setPhoneNumber(String phoneNumber) {
this.phoneNumber = phoneNumber;
}
public boolean getSex() {
return sex;
}
public void setSex(boolean sex) {
this.sex = sex;
}
public Date getBirthYear() {
return birthYear;
}
public void setBirthYear(Date birthYear) {
this.birthYear = birthYear;
}
public String getEmail() {
return email;
}
public void setEmail(String email) {
this.email = email;
}
public String getInfoSource() {
return infoSource;
}
public void setInfoSource(String infoSource) {
this.infoSource = infoSource;
}
public String getOccupation() {
return occupation;
}
public void setOccupation(String occupation) {
this.occupation = occupation;
}
public String getPassword() {
return password;
}
public void setPassword(String password) {
this.password = password;
}
public Set<Unit> getUnitSet() {
return unitSet;
}
public void setUnitSet(Set<Unit> unitSet) {
this.unitSet = unitSet;
}
public Set<Payment> getPaymentSet() {
return paymentSet;
}
public void setPaymentSet(Set<Payment> paymentSet) {
this.paymentSet = paymentSet;
}
public Address getAddress() {
return address;
}
public void setAddress(Address address) {
this.address = address;
}
#Override
public int hashCode() {
int hash = 0;
hash += (id != null ? id.hashCode() : 0);
return hash;
}
#Override
public boolean equals(Object object) {
// TODO: Warning - this method won't work in the case the id fields are
// not set
if (!(object instanceof User)) {
return false;
}
User other = (User) object;
if ((this.id == null && other.id != null)
|| (this.id != null && !this.id.equals(other.id))) {
return false;
}
return true;
}
#Override
public String toString() {
return "com.game.database.entity.User[id=" + id + "]";
}
}
--
package com.game.database.entity;
#Entity
#Table(name = "virtue")
#NamedQueries({
#NamedQuery(name = "Virtue.findAll", query = "SELECT v FROM Virtue v"),
#NamedQuery(name = "Virtue.findById", query = "SELECT v FROM Virtue v WHERE v.id = :id"),
#NamedQuery(name = "Virtue.findByName", query = "SELECT v FROM Virtue v WHERE v.name = :name"),
#NamedQuery(name = "Virtue.findByDescription", query = "SELECT v FROM Virtue v WHERE v.description = :description") })
public class Virtue implements Serializable {
private static final long serialVersionUID = 1L;
#SequenceGenerator(name = "virtue_id_seq", sequenceName = "virtue_id_seq", allocationSize = 1)
#Id
#GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "virtue_id_seq")
#Basic(optional = false)
#Column(name = "id")
private Integer id;
#Basic(optional = false)
#Column(name = "name")
private String name;
#Basic(optional = false)
#Column(name = "description")
private String description;
#OneToMany(cascade = CascadeType.ALL, mappedBy = "virtue")
private Set<Unit> unitSet;
public Virtue() {
}
public Virtue(Integer id) {
this.id = id;
}
public Virtue(String name, String description) {
this.name = name;
this.description = description;
}
public Integer getId() {
return id;
}
public void setId(Integer id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getDescription() {
return description;
}
public void setDescription(String description) {
this.description = description;
}
public Set<Unit> getUnitSet() {
return unitSet;
}
public void setUnitSet(Set<Unit> unitSet) {
this.unitSet = unitSet;
}
#Override
public int hashCode() {
int hash = 0;
hash += (id != null ? id.hashCode() : 0);
return hash;
}
#Override
public boolean equals(Object object) {
// TODO: Warning - this method won't work in the case the id fields are
// not set
if (!(object instanceof Virtue)) {
return false;
}
Virtue other = (Virtue) object;
if ((this.id == null && other.id != null)
|| (this.id != null && !this.id.equals(other.id))) {
return false;
}
return true;
}
#Override
public String toString() {
return "com.game.database.entity.Virtue[id=" + id + "]";
}
}

You have a problem with the identity of the Unit objects. You're using in your code a HashSet which relies on equals and hashCode methods which are overridden in your code.
If you run the main method in the code below, you will see that after adding the Unit objects there is only one of them in the set (I reused your original code but I simplified it a bit):
import java.util.Date;
import java.util.HashSet;
import java.util.Set;
public class Unit {
private Integer id;
private Integer unitId;
private String name;
private Date registrationDate;
private String service;
private String nation;
public Unit() {
}
public Unit(Integer id) {
this.id = id;
}
public Unit(Integer unitId, String name, Date registrationDate, String service, String nation) {
this.unitId = unitId;
this.name = name;
this.registrationDate = registrationDate;
this.service = service;
this.nation = nation;
}
public Integer getId() {
return id;
}
public void setId(Integer id) {
this.id = id;
}
public Integer getUnitId() {
return unitId;
}
public void setUnitId(Integer unitId) {
this.unitId = unitId;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public Date getRegistrationDate() {
return registrationDate;
}
public void setRegistrationDate(Date registrationDate) {
this.registrationDate = registrationDate;
}
public String getService() {
return service;
}
public void setService(String service) {
this.service = service;
}
public String getNation() {
return nation;
}
public void setNation(String nation) {
this.nation = nation;
}
#Override
public int hashCode() {
int hash = 0;
hash += (id != null ? id.hashCode() : 0);
return hash;
}
#Override
public boolean equals(Object object) {
// TODO: Warning - this method won't work in the case the id fields are not set
if (!(object instanceof Unit)) {
return false;
}
Unit other = (Unit) object;
if ((this.id == null && other.id != null) || (this.id != null && !this.id.equals(other.id))) {
return false;
}
return true;
}
#Override
public String toString() {
return "com.game.database.entity.Unit[id=" + id + "]";
}
public static void main(String... args) {
Unit unit1 = new Unit(1, "Test Unit1", new Date(), "DisService", "MyNation");
Unit unit2 = new Unit(2, "Test Unit2", new Date(), "DisService", "TheirNation");
Unit unit3 = new Unit(3, "Test Unit3", new Date(), "DisService", "TheirNation");
Set unitSet = new HashSet();
unitSet.add(unit2);
unitSet.add(unit1);
unitSet.add(unit3);
System.out.println(unitSet.size());
}
If you comment out the equals() and hashCode() and run the code again you will see three objects in the set.
Your equals() method is based on the id property which is set by hibernate at time the object is being persisted and not at the time of adding to the set. It means that the Unit has always a null id and hashCode = 0 when added to the set. I recommend reading this article: http://community.jboss.org/wiki/EqualsandHashCode
Hope it helps!