Hazelcast supports JPA persistence integrated with Spring Data-JPA module. Your POJOs are mapped and persisted to your relational database. To use JPA persistence first you should create a Repository interface extending CrudRepository class with object type that you want to persist..

package com.hazelcast.jpa.repository;

import com.hazelcast.jpa.Product;
import org.springframework.data.repository.CrudRepository;

public interface ProductRepository extends CrudRepository<Product, Long> {

}

Then you should add your data source and repository definition to you Spring configuration,

<jpa:repositories
       base-package="com.hazelcast.jpa.repository" />

    <bean class="com.hazelcast.jpa.SpringJPAMapStore" id="jpamapstore">
        <property name="crudRepository" ref="productRepository" />
    </bean>

    <bean class="org.apache.commons.dbcp.BasicDataSource" destroy-method="close" id="dataSource">
        <property name="driverClassName" value="com.mysql.jdbc.Driver"/>
             <property name="url" value="jdbc:mysql://localhost:3306/YOUR_DB"/>
             <property name="username" value="YOUR_USERNAME"/>
             <property name="password" value="YOUR_PASSWORD"/>
    </bean>

    <bean id="entityManagerFactory"
      class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean">
      <property name="dataSource" ref="dataSource" />
      <property name="jpaVendorAdapter">
        <bean class="org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter">
          <property name="generateDdl" value="true" />
          <property name="database" value="MYSQL" />
        </bean>
      </property>
        <property name="persistenceUnitName" value="jpa.sample" />
    </bean>

    <bean class="org.springframework.orm.jpa.JpaTransactionManager"
      id="transactionManager">
      <property name="entityManagerFactory"
          ref="entityManagerFactory" />
      <property name="jpaDialect">
        <bean class="org.springframework.orm.jpa.vendor.HibernateJpaDialect" />
      </property>
    </bean>
    

In the example configuration above, Hibernate and MYSQL is configured, you change them according your ORM and database selection. Also you should define your persistence unit with persistence.xml under META-INF directory.

<?xml version="1.0" encoding="UTF-8"?>
<persistence version="2.0" xmlns="http://java.sun.com/xml/ns/persistence" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/persistence http://java.sun.com/xml/ns/persistence/persistence_2_0.xsd">
	<persistence-unit name="jpa.sample" />
</persistence>

By default, the key is expected to be the same with id of the JPA object. You can change this behaviour and customize MapStore implementation extending SpringJPAMapStore class. For more info see Spring Data JPA Reference .