java.lang.IllegalStateException: Multiple representations of the same entity with @ManyToMany 3 entities

Question

I have 3 entities with ManyToMany relationships:

Role Entity:

@Entity public class Role {     @Id     @GeneratedValue(strategy = GenerationType.IDENTITY)     private Integer roleID;     private String roleName;     private String description;      @ManyToMany(cascade = {CascadeType.MERGE, CascadeType.PERSIST, CascadeType.REFRESH}, fetch = FetchType.EAGER)     @JoinTable(name = "role_permission", joinColumns = {@JoinColumn(name = "role_id")}, inverseJoinColumns = {@JoinColumn(name = "permission_id")})     private Set<Permission> permissions = new LinkedHashSet<Permission>(); } 

Permission Entity:

@Entity public class Permission {     @Id     @GeneratedValue(strategy = GenerationType.IDENTITY)     private int permissionID;     private String permissionName;     private String description;      @ManyToMany(cascade = {CascadeType.MERGE, CascadeType.PERSIST, CascadeType.REFRESH}, fetch = FetchType.EAGER)     @JoinTable(name = "permission_functionality", joinColumns = {@JoinColumn(name = "permission_id")}, inverseJoinColumns = {@JoinColumn(name = "functionality_id")})     private Set<Functionality> functionalities = new LinkedHashSet<>(); } 

Functionality Entity:

@Entity public class Functionality {     @Id     @GeneratedValue(strategy = GenerationType.IDENTITY)     private Integer id;     private String name; } 

I did the following:

1. I have created 3 functionalities:

   Functionality1, Functionality2, Functionality3 

2. Then created 2 permissions:

   Permission1 with Functionality1, Functionality2  Permission2 with Functionality2, Functionality3 

3. Then created a role:

   Role1 with Permission1 and Permission2  

I am getting the following exception:

java.lang.IllegalStateException: Multiple representations of the same entity [com.persistence.entity.admin.Functionality#1] are being merged. Detached: [com.persistence.entity.admin.Functionality@4729256a]; Detached: [com.persistence.entity.admin.Functionality@56ed25db]

Answer 1

Fixed it by removing CascadeType.MERGE on Permission entity