JPA query for 3 tables - sql

Question

I want to create JPA query for configuring multiple Terminals to one Contract:
CREATE TABLE `contracts` (
`id` int(11) NOT NULL AUTO_INCREMENT,
`name` varchar(255) DEFAULT NULL,
) ENGINE=InnoDB;
CREATE TABLE `contracts_terminals` (
`terminal_id` int(11) DEFAULT NULL,
`contract_id` int(11) DEFAULT NULL,
) ENGINE=InnoDB;
CREATE TABLE `terminals` (
`id` int(11) NOT NULL AUTO_INCREMENT,
`name` varchar(255) DEFAULT NULL,
PRIMARY KEY (`id`),
) ENGINE=InnoDB;
How I can create JPA query which uses table contracts_terminals to assign multiple terminals to one contract?
I use latest MariaDB.
Entities:
Contracts:
#Entity
#Table(name = "contracts")
public class Contracts implements Serializable {
private static final long serialVersionUID = 3873648042962238717L;
#Id
#GeneratedValue(strategy = GenerationType.AUTO)
#Column(name = "id", unique = true, updatable = false, nullable = false)
private int id;
#Column(length = 255)
private String name;
......
}
Terminals:
#Entity
#Table(name = "terminals")
public class Terminals implements Serializable {
private static final long serialVersionUID = 5288308199642977991L;
#Id
#GeneratedValue(strategy = GenerationType.AUTO)
#Column(name = "id", unique = true, updatable = false, nullable = false, length = 3)
private int id;
#Column(length = 255)
private String name;
....
}
ContractTerminals:
#Entity
#Table(name = "contract_terminals")
public class ContractTerminals implements Serializable {
private static final long serialVersionUID = 1191148141983861602L;
#Id
#GeneratedValue(strategy = GenerationType.AUTO)
#Column(name = "id", unique = true, updatable = false, nullable = false)
private int id;
#Column(length = 4)
private Integer terminal_id;
#Column(length = 4)
private Integer contract_id;
....
}