Spring Boot EntityManagerFactoryBuilder 未自动装配

Question

In a Spring Boot application I'm trying to setup multiple database connections. I've started building the primary datasource, but I'm getting the following error on the mySqlEntityManagerFactory method.

Could not autowire. no beans of EntityManagerFactoryBuilder

import org.springframework.boot.autoconfigure.jdbc.DataSourceBuilder;
import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.boot.orm.jpa.EntityManagerFactoryBuilder;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Primary;
import org.springframework.data.jpa.repository.config.EnableJpaRepositories;
import org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean;
import org.springframework.transaction.annotation.EnableTransactionManagement;
import org.springframework.transaction.annotation.Transactional;

import javax.persistence.PersistenceContext;
import javax.sql.DataSource;
import java.util.HashMap;
import java.util.Map;

@Configuration
@Transactional
@EnableTransactionManagement
@EnableJpaRepositories(
        basePackages = "digital.sheppard.dao",
        entityManagerFactoryRef = "entityManager",
        transactionManagerRef = "transactionManager")
public class PrimaryDBConfig {

    @Bean(name="dataSource")
    @Primary
    @ConfigurationProperties(prefix = "primary.datasource.mysql")
    public DataSource mysqlDataSource() {
        return DataSourceBuilder.create().build();
    }

    @PersistenceContext(unitName = "primary")
    @Primary
    @Bean(name = "entityManager")
    public LocalContainerEntityManagerFactoryBean mySqlEntityManagerFactory(EntityManagerFactoryBuilder builder) {
        return builder.dataSource(mysqlDataSource()).persistenceUnit("primary").properties(jpaProperties())
                .packages("digital.sheppard.model").build();
    }

    private Map<String, Object> jpaProperties() {
        Map<String, Object> props = new HashMap<String, Object>();
        props.put("hibernte.ejb.naming_strategy", "org.hibernate.cfg.ImprovedNamingStrategy");
        props.put("hibernate.dialect", "org.hibernate.dialect.MySQL5Dialect");

        return props;
    }

}

How would I autowire the EntityManagerFactoryBuilder?

I'm trying to follow the code on this blog https://raymondhlee.wordpress.com/2015/10/31/configuring-multiple-jpa-entity-managers-in-spring-boot/

Here's the main application class if it's helpful

@Configuration
@EnableAutoConfiguration(exclude={DataSourceAutoConfiguration.class})
@ComponentScan
public class Application extends SpringBootServletInitializer {

    public static void main(String[] args) {
        SpringApplication.run(Application.class, args);
    }

}

Answer 1

我认为您应该删除此代码

@EnableAutoConfiguration(exclude={DataSourceAutoConfiguration.class})

Answer 2

将参数名称builder更改为entityManagerFactoryBuilder以注入 JpaBaseConfiguration.class 中的 bean

Answer 3

Have you tried to remove your exclusion of 'DataSourceAutoConfiguration' ?

Using '@EnableAutoConfiguration(exclude={DataSourceAutoConfiguration.class})' prevent a lot of beans from beeing created.

If you got a problem when using a datasource and adding this is your solution, maybe it's not the right one.

Know that spring boot detect the presence of certain classes in the classpath. If you're using maven, it's reading all classes from all dependencies.

So consider let this DataSourceAutoConfiguration.class running;

cheers

Answer 4

It could be, notice that just could be, your main class is not at the top of the "class tree". Spring needs to scan all classes that are a child (according to package convention) starting from the main class.

Maybe you would read https://www.baeldung.com/spring-component-scanning

If your classes aren't been read by spring scan, they will never be into spring context.

Answer 5

Couple of possibilities : You need to add the @EnableJpaRepositories(basePackages = {"your.pkg.here"}) to the Application . This tells Spring Data to look for your repository classes under the specified package.

Answer 6

The exception is due to public LocalContainerEntityManagerFactoryBean mySqlEntityManagerFactory(EntityManagerFactoryBuilder builder) { which expects a bean of EntityManagerFactoryBuilder .

I checked the reference link, I am not sure if that code will work.

Typically, one creates an instance of LocalContainerEntityManagerFactoryBean and initializes it as per need. In your case you can do

  LocalContainerEntityManagerFactoryBean em = new LocalContainerEntityManagerFactoryBean();
  em.setDataSource(mysqlDataSource());
  em.setPersistenceUnitName("primary");
  em.setPackagesToScan(new String[] { "digital.sheppard.model" });

  JpaVendorAdapter vendorAdapter = new HibernateJpaVendorAdapter();
  em.setJpaVendorAdapter(vendorAdapter);
  em.setJpaProperties(jpaProperties());

The persistence unit name should be same as defined in persistence.xml , though the file is now optional when using Spring JPA.

For a non spring version check out https://stackoverflow.com/a/26814642/776548

Also

• since you are initializing EntityManagerFactory by yourself, we will have to exclude DataSourceAutoConfiguration.class .
• @Primary is only required if you want multiple datasources. If you have only one, consider removing the annotation, and add it when you need to have multiple data sources

Answer 7

对我来说，删除错误添加的多个数据源上的@Primary 解决了这个问题

Answer 8

it was caused by your ide software,set up these options