Inject DataSource to LocalContainerEntityManagerFactoryBean

If you already have a DataSource define you can just inject it into your EntityManagerFactory.

package com.example.jpa;

import javax.inject.Inject;
import javax.sql.DataSource;

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.orm.jpa.JpaTransactionManager;
import org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean;
import org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter;
import org.springframework.transaction.PlatformTransactionManager;
import org.springframework.transaction.annotation.EnableTransactionManagement;

import com.example.model.Customer;

@Configuration
@EnableTransactionManagement
public class JpaInjectDataSourceConfiguration {

	@Inject DataSource dataSource;

  	@Bean
    public LocalContainerEntityManagerFactoryBean entityManagerFactory() throws Exception {

        LocalContainerEntityManagerFactoryBean localContainerEntityManagerFactoryBean = new LocalContainerEntityManagerFactoryBean();
        localContainerEntityManagerFactoryBean.setDataSource(dataSource);
        localContainerEntityManagerFactoryBean.setPackagesToScan(Customer.class.getPackage().getName());

        HibernateJpaVendorAdapter jpaVendorAdapter = new HibernateJpaVendorAdapter();
        jpaVendorAdapter.setGenerateDdl(true);

        localContainerEntityManagerFactoryBean.setJpaVendorAdapter(jpaVendorAdapter);
        return localContainerEntityManagerFactoryBean;
    }

    @Bean
    public PlatformTransactionManager transactionManager(javax.persistence.EntityManagerFactory entityManagerFactory) throws Exception {
        return new JpaTransactionManager(entityManagerFactory);
    }
}