java Spring Boot EntityManagerFactoryBuilder 未自动装配

Spring Boot EntityManagerFactoryBuilder not autowired

提问by SheppardDigital

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.

在 Spring Boot 应用程序中，我试图设置多个数据库连接。我已经开始构建主数据源，但是在 mySqlEntityManagerFactory 方法上出现以下错误。

Could not autowire. no beans of EntityManagerFactoryBuilder

无法自动装配。没有 EntityManagerFactoryBuilder 的 bean

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?

我将如何自动装配 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/

我正在尝试遵循此博客上的代码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

如果有帮助，这是主要的应用程序类

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

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

}

回答by Alexandre Souza Peron

Change parameter name builderto entityManagerFactoryBuilderto inject bean present in JpaBaseConfiguration.class

更改参数名称builder以entityManagerFactoryBuilder对存在于JpaBaseConfiguration.class注入豆

回答by Y.Ido

I think you should remove this code

我认为您应该删除此代码

@EnableAutoConfiguration(exclude={DataSourceAutoConfiguration.class})

回答by cehdmoy

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.

可能是，注意可能是，您的主类不在“类树”的顶部。Spring 需要从主类开始扫描所有子类（根据包约定）。

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

也许您会阅读https://www.baeldung.com/spring-component-scanning

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

如果您的类没有被 spring 扫描读取，它们将永远不会进入 spring 上下文。

回答by Akash

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.

几种可能性：您需要将 @EnableJpaRepositories(basePackages = {"your.pkg.here"}) 添加到 Application 。这告诉 Spring Data 在指定的包下查找您的存储库类。

回答by Archit

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

例外是由于public LocalContainerEntityManagerFactoryBean mySqlEntityManagerFactory(EntityManagerFactoryBuilder builder) {which 期望一个 bean EntityManagerFactoryBuilder。

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

我检查了参考链接，我不确定该代码是否有效。

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

通常，创建 LocalContainerEntityManagerFactoryBean 的实例并根据需要对其进行初始化。在你的情况下，你可以做

  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.

持久性单元名称应与 中定义的相同persistence.xml，尽管在使用 Spring JPA 时该文件现在是可选的。

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

对于非弹簧版本，请查看https://stackoverflow.com/a/26814642/776548

Also

还

• since you are initializing EntityManagerFactory by yourself, we willhave to exclude DataSourceAutoConfiguration.class.
• @Primaryis 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

• 由于您是自己初始化 EntityManagerFactory，我们将不得不排除DataSourceAutoConfiguration.class.
• @Primary仅当您需要多个数据源时才需要。如果只有一个，可以考虑去掉注解，当需要有多个数据源时再添加

回答by Mathan

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

您是否尝试删除对 'DataSourceAutoConfiguration' 的排除？

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

使用 '@EnableAutoConfiguration(exclude={DataSourceAutoConfiguration.class})' 可以防止创建大量 bean。

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

如果您在使用数据源时遇到问题并添加这是您的解决方案，则可能它不是正确的。

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.

知道 spring boot 会检测类路径中某些类的存在。如果您使用的是 maven，它会从所有依赖项中读取所有类。

So consider let this DataSourceAutoConfiguration.class running;

所以考虑让这个 DataSourceAutoConfiguration.class 运行；

cheers

干杯

回答by D.Mummy

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

这是由你的ide软件引起的，设置这些选项