Question

我从http://start.spring.io/创建了一个简单项目（1.3.2 with WEB，JPA）并尝试创建两个EntityManager，但我得到以下异常。任何想法有什么不对或我怎么能让它运作？

org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'transactionManager' defined in class path resource [com/example/SecondDataSourceConfiguration.class]: Unsatisfied dependency expressed through constructor argument with index 0 of type [javax.persistence.EntityManagerFactory]: : No qualifying bean of type [javax.persistence.EntityManagerFactory] is defined: expected single matching bean but found 2: entityManagerFactoryFirst,entityManagerFactorySecond; nested exception is org.springframework.beans.factory.NoUniqueBeanDefinitionException: No qualifying bean of type [javax.persistence.EntityManagerFactory] is defined: expected single matching bean but found 2: entityManagerFactoryFirst,entityManagerFactorySecond
    at org.springframework.beans.factory.support.ConstructorResolver.createArgumentArray(ConstructorResolver.java:749) ~[spring-beans-4.2.4.RELEASE.jar:4.2.4.RELEASE]
    at org.springframework.beans.factory.support.ConstructorResolver.instantiateUsingFactoryMethod(ConstructorResolver.java:464) ~[spring-beans-4.2.4.RELEASE.jar:4.2.4.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateUsingFactoryMethod(AbstractAutowireCapableBeanFactory.java:1123) ~[spring-beans-4.2.4.RELEASE.jar:4.2.4.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1018) ~[spring-beans-4.2.4.RELEASE.jar:4.2.4.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:510) ~[spring-beans-4.2.4.RELEASE.jar:4.2.4.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:482) ~[spring-beans-4.2.4.RELEASE.jar:4.2.4.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:306) ~[spring-beans-4.2.4.RELEASE.jar:4.2.4.RELEASE]
    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230) ~[spring-beans-4.2.4.RELEASE.jar:4.2.4.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:302) ~[spring-beans-4.2.4.RELEASE.jar:4.2.4.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:197) ~[spring-beans-4.2.4.RELEASE.jar:4.2.4.RELEASE]
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:772) ~[spring-beans-4.2.4.RELEASE.jar:4.2.4.RELEASE]
    at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:839) ~[spring-context-4.2.4.RELEASE.jar:4.2.4.RELEASE]
    at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:538) ~[spring-context-4.2.4.RELEASE.jar:4.2.4.RELEASE]
    at org.springframework.boot.context.embedded.EmbeddedWebApplicationContext.refresh(EmbeddedWebApplicationContext.java:118) ~[spring-boot-1.3.2.RELEASE.jar:1.3.2.RELEASE]
    at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:766) [spring-boot-1.3.2.RELEASE.jar:1.3.2.RELEASE]
    at org.springframework.boot.SpringApplication.createAndRefreshContext(SpringApplication.java:361) [spring-boot-1.3.2.RELEASE.jar:1.3.2.RELEASE]
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:307) [spring-boot-1.3.2.RELEASE.jar:1.3.2.RELEASE]
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:1191) [spring-boot-1.3.2.RELEASE.jar:1.3.2.RELEASE]
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:1180) [spring-boot-1.3.2.RELEASE.jar:1.3.2.RELEASE]
    at com.example.DemoApplication.main(DemoApplication.java:12) [classes/:na]
Caused by: org.springframework.beans.factory.NoUniqueBeanDefinitionException: No qualifying bean of type [javax.persistence.EntityManagerFactory] is defined: expected single matching bean but found 2: entityManagerFactoryFirst,entityManagerFactorySecond
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1126) ~[spring-beans-4.2.4.RELEASE.jar:4.2.4.RELEASE]
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1014) ~[spring-beans-4.2.4.RELEASE.jar:4.2.4.RELEASE]
    at org.springframework.beans.factory.support.ConstructorResolver.resolveAutowiredArgument(ConstructorResolver.java:813) ~[spring-beans-4.2.4.RELEASE.jar:4.2.4.RELEASE]
    at org.springframework.beans.factory.support.ConstructorResolver.createArgumentArray(ConstructorResolver.java:741) ~[spring-beans-4.2.4.RELEASE.jar:4.2.4.RELEASE]
    ... 19 common frames omitted

FristDataSourceConfiguration

package com.example;

import java.beans.PropertyVetoException;
import java.sql.SQLException;
import java.util.HashMap;
import java.util.Map;

import javax.persistence.EntityManagerFactory;
import javax.persistence.PersistenceContext;
import javax.sql.DataSource;

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Primary;
import org.springframework.jdbc.datasource.embedded.EmbeddedDatabase;
import org.springframework.jdbc.datasource.embedded.EmbeddedDatabaseBuilder;
import org.springframework.jdbc.datasource.embedded.EmbeddedDatabaseType;
import org.springframework.orm.jpa.JpaTransactionManager;
import org.springframework.orm.jpa.JpaVendorAdapter;
import org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean;
import org.springframework.orm.jpa.vendor.Database;
import org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter;
import org.springframework.transaction.PlatformTransactionManager;
import org.springframework.transaction.annotation.EnableTransactionManagement;

@Configuration
@EnableTransactionManagement
public class FristDataSourceConfiguration {

    @Bean
    @Primary
    public DataSource dataSource() throws SQLException {

        EmbeddedDatabaseBuilder builder = new EmbeddedDatabaseBuilder();
        EmbeddedDatabase db = builder.setType( EmbeddedDatabaseType.H2 ).build();
        return db;
    }

    @PersistenceContext(unitName = "first")
    @Bean(name = "entityManagerFactoryFirst")
    public LocalContainerEntityManagerFactoryBean entityManagerFactory() throws PropertyVetoException, SQLException {
        LocalContainerEntityManagerFactoryBean emf = new LocalContainerEntityManagerFactoryBean();
        emf.setDataSource( dataSource() );
        emf.setJpaVendorAdapter( vendorAdapter() );
        emf.setPersistenceUnitName( "first" );
        emf.setPackagesToScan( "com.demo.domain" );
        emf.setJpaPropertyMap( getJpaProperties() );

        return emf;
    }

    public Map<String, String> getJpaProperties() {

        Map<String, String> jpaMap = new HashMap<String, String>();
        jpaMap.put( "hibernate.cache.use_query_cache", "false" );
        jpaMap.put( "hibernate.cache.use_second_level_cache", "false" );
        return jpaMap;
    }

    @Bean
    public PlatformTransactionManager transactionManager( EntityManagerFactory emf ) {
        JpaTransactionManager transactionManager = new JpaTransactionManager();
        transactionManager.setEntityManagerFactory( emf );

        return transactionManager;
    }

    public JpaVendorAdapter vendorAdapter() {
        HibernateJpaVendorAdapter hibernateJpaVendorAdapter = new HibernateJpaVendorAdapter();
        hibernateJpaVendorAdapter.setShowSql( true );
        hibernateJpaVendorAdapter.setGenerateDdl( true );
        hibernateJpaVendorAdapter.setDatabase( Database.H2 );
        return hibernateJpaVendorAdapter;
    }
}

SecondDataSourceConfiguration

package com.example;

import java.beans.PropertyVetoException;
import java.sql.SQLException;
import java.util.HashMap;
import java.util.Map;

import javax.persistence.EntityManagerFactory;
import javax.persistence.PersistenceContext;
import javax.sql.DataSource;

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Primary;
import org.springframework.jdbc.datasource.embedded.EmbeddedDatabase;
import org.springframework.jdbc.datasource.embedded.EmbeddedDatabaseBuilder;
import org.springframework.jdbc.datasource.embedded.EmbeddedDatabaseType;
import org.springframework.orm.jpa.JpaTransactionManager;
import org.springframework.orm.jpa.JpaVendorAdapter;
import org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean;
import org.springframework.orm.jpa.vendor.Database;
import org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter;
import org.springframework.transaction.PlatformTransactionManager;
import org.springframework.transaction.annotation.EnableTransactionManagement;

@Configuration
@EnableTransactionManagement
public class SecondDataSourceConfiguration {

    @Bean
    @Primary
    public DataSource dataSource() throws SQLException {

        EmbeddedDatabaseBuilder builder = new EmbeddedDatabaseBuilder();
        EmbeddedDatabase db = builder.setType( EmbeddedDatabaseType.H2 ).build();
        return db;
    }

    @PersistenceContext(unitName = "second")
    @Bean(name = "entityManagerFactorySecond")
    public LocalContainerEntityManagerFactoryBean entityManagerFactory() throws PropertyVetoException, SQLException {
        LocalContainerEntityManagerFactoryBean emf = new LocalContainerEntityManagerFactoryBean();
        emf.setDataSource( dataSource() );
        emf.setJpaVendorAdapter( vendorAdapter() );
        emf.setPersistenceUnitName( "second" );
        emf.setPackagesToScan( "com.demo.domain" );
        emf.setJpaPropertyMap( getJpaProperties() );

        return emf;
    }

    public Map<String, String> getJpaProperties() {

        Map<String, String> jpaMap = new HashMap<String, String>();
        jpaMap.put( "hibernate.cache.use_query_cache", "false" );
        jpaMap.put( "hibernate.cache.use_second_level_cache", "false" );
        return jpaMap;
    }

    @Bean
    public PlatformTransactionManager transactionManager( EntityManagerFactory emf ) {
        JpaTransactionManager transactionManager = new JpaTransactionManager();
        transactionManager.setEntityManagerFactory( emf );

        return transactionManager;
    }

    public JpaVendorAdapter vendorAdapter() {
        HibernateJpaVendorAdapter hibernateJpaVendorAdapter = new HibernateJpaVendorAdapter();
        hibernateJpaVendorAdapter.setShowSql( true );
        hibernateJpaVendorAdapter.setGenerateDdl( true );
        hibernateJpaVendorAdapter.setDatabase( Database.H2 );
        return hibernateJpaVendorAdapter;
    }
}

的pom.xml

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>com.example</groupId>
    <artifactId>demo</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <packaging>jar</packaging>

    <name>demo</name>
    <description>Demo project for Spring Boot</description>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>1.3.2.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>

    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <java.version>1.8</java.version>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-jpa</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>

        <dependency>
            <groupId>com.h2database</groupId>
            <artifactId>h2</artifactId>
            <version>1.4.191</version>
        </dependency>

    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>


</project>

Answer 1

你的方法

public PlatformTransactionManager transactionManager( EntityManagerFactory emf )

需要一个EntityManagerFactory并创建两个。您可以使用@Qualifer来配置哪个位置。您还应该禁用DataSourceAutoConfiguration，因此spring不会创建一个。请参阅此处获取完整的教程： Configuring Multiple JPA Entity Managers In Spring Boot

Answer 2

首先，我需要在主文件中排除HibernateJpaAutoConfiguration。

 @SpringBootApplication(exclude = HibernateJpaAutoConfiguration.class)

和第二个我需要添加@Qualifier注释

    @Bean
    public PlatformTransactionManager transactionManager( @Qualifier("entityManagerFactorySecond" ) EntityManagerFactory emf) {
        JpaTransactionManager transactionManager = new JpaTransactionManager();
        transactionManager.setEntityManagerFactory( emf );

        return transactionManager;
    }

Spring Boot多个EntityManagerFactories NoUniqueBeanDefinitionException

2 个答案: