JPA annotations Implement Federated primary keys

When a primary key in a table cannot uniquely identify a record, the federated primary key is required, and the following is the code that implements the federated primary key using the JPA annotations

1 You first need to create a composite primary key class to hold the attributes that require the production of a federated primary key, which needs to be serialized.

Package com.ericsson.adp.entity.cons;

import java.io.Serializable;

Public class CONSUMERGROUPMAPPK Implements serializable{

Private String msisdn;//Phone Number

Private Long taggroupid;//(10) Tag Group ID

Public String getmsisdn () {

return msisdn;

}

Public void setmsisdn (String msisdn) {

this. msisdn = MSISDN;

}

Public Long Gettaggroupid () {

return taggroupid;

}

Public void settaggroupid (Long taggroupid) {

this. taggroupid = Taggroupid;

}

}

Then write a class that corresponds to a table in the database that requires the use of @idclass (CONSUMERGROUPMAPPK) in this class. Class) introduces the composite primary key class written above

At the same time, the attribute that needs to be the Union primary key plus @id indicates that the attribute is the primary key.

Package com.ericsson.adp.entity.cons;

Import javax.persistence.EmbeddedId;

import javax.persistence.Entity;

import javax.persistence.Id;

import Javax.persistence.IdClass;

import javax.persistence.Table;

import Org.hibernate.annotations.Cache;

import org.hibernate.annotations.CacheConcurrencyStrategy;

@Entity

@IdClass (CONSUMERGROUPMAPPK. Class)

@Table (name= "T_cons_consumer_group_map")

@Cache (usage=cacheconcurrencystrategy. Read_write)

Public class consumergroupmap{

@Id

Private String msisdn;//Phone Number

@Id

Private Long taggroupid;//(10) Tag Group ID

Public Consumergroupmap () {

Super ();

TODO auto-generated constructor stub

}

Public Consumergroupmap (String msisdn, Long taggroupid) {

Super ();

this. msisdn = MSISDN;

this. taggroupid = Taggroupid;

}

Public String getmsisdn () {

return msisdn;

}

Public void setmsisdn (String msisdn) {

this. msisdn = MSISDN;

}

Public Long Gettaggroupid () {

return taggroupid;

}

Public void settaggroupid (Long taggroupid) {

this. taggroupid = Taggroupid;

}

}

JPA annotations Implement Federated primary keys