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POHibernate @ManyToMany delete relation
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  1. POHibernate @ManyToMany delete relation
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    copied!<p>I have 2 entities: User and UsersList.</p> <pre><code>@Entity @Table(name = "USERS") public class User { @Id @GeneratedValue @Column(name = "ID") private Long id; @ManyToMany(cascade = CascadeType.REMOVE, mappedBy = "users") private List&lt;UsersList&gt; usersLists = new ArrayList&lt;UsersList&gt;(); public List&lt;UsersList&gt; getUsersLists() { return usersLists; } public void setUsersLists(List&lt;UsersList&gt; usersLists) { this.usersLists = usersLists; } } </code></pre> <p>and</p> <pre><code>@Entity @Table(name = "USERS_LIST") public class UsersList { @Id @GeneratedValue @Column(name = "ID") private Long id; @ManyToMany private List&lt;User&gt; users = new ArrayList&lt;User&gt;(); public List&lt;User&gt; getUsers() { return users; } public void setUsers(List&lt;User&gt; users) { this.users = users; } } </code></pre> <p>and code like this one:</p> <pre><code>// 1 List&lt;User&gt; dbUsers; // 3 the user instances are persisted in DB UsersList usersList = new UsersList(); usersList.setUsers(dbUsers); // 2 - now persist the usersList using hibernate... saveWithHibernate(usersList); //3 - delete using a persisted user deleteWithHibernate(dbUsers.get(0).getId()); </code></pre> <p>where </p> <pre><code>deleteWithHibernate(Long id) { User usr = hibernateTemplate.get(User.class, id); hibernateTemplate.delete(usr); } </code></pre> <p>In step 1 I have 3 rows in the USERS (USER_ID) table.</p> <p>After step 2 (second comment) I have 1 row in the USERS_LIST (USERS_LIST_ID) table and into the join table USERS_LIST_USERS (USER_ID, USERS_LIST_ID) 3 rows. </p> <p>What I want to achieve in step 3 is the following: when I delete one user from the table USERS - let's say user with USER_ID = 4, I want just the row with USER_ID = 4 from the join table to be deleted, and the others to remain.</p> <p>Is there an annotation solution to my problem?</p>
 

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