I need to Associate two entities in @Manytomany with JPA using Mysql, but it is not saved in the composite table (usuario_item)

Question

I need to make the connection between user and item for a login system

I’m stagnant in this error 2 days ago. I searched for forums and tutorials and could not get anything to help me.
If possible give me tips on how to do more efficient research on, I come here when I see no other option.

> WARN:

• 2020-10-29 12:36:13.074 WARN 38324 --- [ main] Configservletwebserverapplicationcontext : Exception encountered During context initialization - cancelling refresh Attempt: org.springframework.Beans.factory.Beancreationexception: Error creating bean with name 'usuarioRepository' defined in com.fcc.ads.turmad.nunesdaniel.appweb.repositories.UsuarioRepository defined in @EnableJpaRepositories declared on JpaRepositoriesRegistrar.EnableJpaRepositoriesConfiguration: Cannot resolve Reference to bean 'jpaMappingContext' while Setting bean Property 'mappingContext'; nested Exception is org.springframework.Beans.factory.Beancreationexception: Error Creating bean with name 'jpaMappingContext': Invocation of init method failed; nested Exception is javax.persistence.Persistenceexception: [Persistenceunit: default] Unable to build Hibernate Sessionfactory; nested Exception is org.hibernate.Mappingexception: Could not determine type for: java.util.Set, at table: usuario, for Columns: [org.hibernate.Mapping.Column(items)]
• 2020-10-29 12:36:13.076 WARN 38324 --- [ main] o.s.b.f.support.DisposableBeanAdapter : Invocation of destroy method failed on bean with name 'entityManagerFactory': javax.persistence.PersistenceException: [PersistenceUnit: default] Unable to build Hibernate Sessionfactory; nested Exception is org.hibernate.Mappingexception: Could not determine type for: java.util.Set, at table: usuario, for Columns: [org.hibernate.Mapping.Column(items)]

> LOGS:

• org.springframework.Beans.factory.Beancreationexception: Error creating bean with name 'usuarioRepository' defined in com.fcc.ads.turmad.nunesdaniel.appweb.repositories.UsuarioRepository defined in @EnableJpaRepositories declared on JpaRepositoriesRegistrar.EnableJpaRepositoriesConfiguration: Cannot resolve Reference to bean 'jpaMappingContext' while Setting bean Property 'mappingContext'; nested Exception is org.springframework.Beans.factory.Beancreationexception: Error Creating bean with name 'jpaMappingContext': Invocation of init method failed; nested Exception is javax.persistence.Persistenceexception: [Persistenceunit: default] Unable to build Hibernate Sessionfactory; nested Exception is org.hibernate.Mappingexception: Could not determine type for: java.util.Set, at table: usuario, for Columns: [org.hibernate.Mapping.Column(items)]
• Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'jpaMappingContext': Invocation of init method failed; nested exception is javax.persistence.PersistenceException: [PersistenceUnit: default] Unable to build Hibernate SessionFactory; nested Exception is org.hibernate.Mappingexception: Could not determine type for: java.util.Set, at table: usuario, for Columns: [org.hibernate.Mapping.Column(items)]
• Caused by: javax.persistence.PersistenceException: [PersistenceUnit: default] Unable to build Hibernate SessionFactory; nested exception is org.hibernate.MappingException: Could not determine type for: java.util.Set, at table: usuario, for columns: [org.hibernate.mapping.Column(items)]
• Caused by: org.hibernate.Mappingexception: Could not determine type for: java.util.Set, at table: usuario, for Columns: [org.hibernate.Mapping.Column(items)]

> SQL SCRIPT:

create database app_web_estoque;

use app_web_estoque;

create table item (
    id int not null auto_increment,
    nome varchar(45),
    marca varchar(45),
    quantidade int,
    preco double,
    primary key (id)
);

create table usuario(
    id int not null auto_increment,
    nome varchar(45),
    nomeacesso varchar(45),
    senha varchar(45),
    items int,
    primary key (id)
);

create table usuario_item (
    usuario_id int not null,
    item_id int not null,
    foreign key (usuario_id) references usuario(id),
    foreign key (item_id) references item(id)
);

> ENTITIES:

User

@Entity
@Table(name="usuario")
public class Usuario implements Serializable {
    private static final long serialVersionUID = 1L;

    // outros atributos

    @ManyToMany(fetch = FetchType.LAZY, cascade = CascadeType.ALL, mappedBy="usuarios")
    private Set items = new HashSet();
    
    public Usuario() {
    }
    
    public Usuario(Long id, String nome, String nomeacesso, String senha) {
        this.id = id;
        this.nome = nome;
        this.nomeacesso = nomeacesso;
        this.senha = senha;
    }

    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    public Long getId() {
        return id;
    }

    // getters e setters

    public Set getItems() {
        return items;
    }
}

Item

@Entity
@Table(name="item")
public class Item implements Serializable {
    private static final long serialVersionUID = 1L;
    
    // outros atributos

    @ManyToMany(fetch = FetchType.LAZY, cascade = CascadeType.ALL)
    @JoinTable(name="usuario_item", 
        joinColumns= {@JoinColumn(name="item_id")}, 
        inverseJoinColumns= {@JoinColumn(name="usuario_id")})
    private Set usuarios = new HashSet();
    
    public Item() {
    }
    
    public Item(Long id, String nome, String marca, Integer quantidade, Double preco) {
        this.id = id;
        this.nome = nome;
        this.marca = marca;
        this.quantidade = quantidade;
        this.preco = preco;
    }

    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    public Long getId() {
        return id;
    }

    // getters e setters
    
    public Set getUsuarios() {
        return usuarios;
    }
}

> DEPENDENCIES:

org.springframework.boot
spring-boot-starter-data-jpa


org.springframework.boot
spring-boot-starter-thymeleaf


org.springframework.boot
spring-boot-starter-we


mysql
mysql-connector-java
runtime

> PROPERTIES:

spring.jpa.hibernate.ddl-auto=none
spring.datasource.url=jdbc:mysql://localhost:3306/app_web_estoque?useTimezone=true&serverTimezone=UTC
spring.datasource.username=admin
spring.datasource.password=admin
spring.jpa.open-in-view=false