Java Spring JPA配置IllegalArgumentException:未找到名为的持久化单元

我遇到了一个奇怪的问题，我想不起来了。我以前使用过JPA/Hibernate is Spring，没有persistence.xml文件，Spring处理了所有事情。我正在做一个新项目，这次我决定全部使用Java配置。我的PersistenceConfig.java有一些问题，它一直说找不到持久性单元。如果我注释掉设置PersistenceUnitName的行，那么它会抱怨IllegalStateException：没有从{classpath*：META-INF/persistence.xml}解析的持久性单元

我不明白为什么在我使用Java配置时要尝试使用persistence.xml，而在我使用xml时却没有。有什么解决办法吗

这是我的PersistenceConfig.java

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.core.env.Environment;
import org.springframework.dao.annotation.PersistenceExceptionTranslationPostProcessor;
import org.springframework.data.jpa.repository.config.EnableJpaRepositories;
import org.springframework.jdbc.datasource.lookup.JndiDataSourceLookup;
import org.springframework.orm.jpa.JpaDialect;
import org.springframework.orm.jpa.JpaTransactionManager;
import org.springframework.orm.jpa.JpaVendorAdapter;
import org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean;
import org.springframework.orm.jpa.vendor.HibernateJpaDialect;
import org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter;
import org.springframework.transaction.PlatformTransactionManager;
import org.springframework.transaction.annotation.EnableTransactionManagement;

import javax.persistence.EntityManagerFactory;
import javax.sql.DataSource;
import java.util.Properties;

@Configuration
@EnableTransactionManagement
@EnableJpaRepositories(basePackages = {"com.testapp.ots.repository"})
public class PersistenceConfig {

    @Autowired
    Environment environment;

    @Bean(name = "datasource")
    public DataSource dataSource() {
        JndiDataSourceLookup dsLookup = new JndiDataSourceLookup();
        dsLookup.setResourceRef(true);
        return dsLookup.getDataSource("jdbc/postgres");
    }

    @Bean(name = "entityManagerFactory")
    public LocalContainerEntityManagerFactoryBean entityManagerFactory() {
        LocalContainerEntityManagerFactoryBean entityManagerFactory = new LocalContainerEntityManagerFactoryBean();
        entityManagerFactory.setDataSource(dataSource());
        entityManagerFactory.setPersistenceUnitName("postgres");
        entityManagerFactory.setJpaProperties(jpaProperties());
        entityManagerFactory.setJpaVendorAdapter(jpaVendorAdapter());
        entityManagerFactory.setJpaDialect(jpaDialect());
        return entityManagerFactory;
    }

    @Bean(name = "jpaVendorAdapter")
    public JpaVendorAdapter jpaVendorAdapter() {
        HibernateJpaVendorAdapter vendorAdapter = new HibernateJpaVendorAdapter();
        vendorAdapter.setDatabasePlatform("org.hibernate.dialect.PostgreSQL9Dialect");
        vendorAdapter.setGenerateDdl(true);
        vendorAdapter.setShowSql(true);
        return vendorAdapter;
    }

    @Bean(name = "jpaDialect")
    public JpaDialect jpaDialect() {
        return new HibernateJpaDialect();
    }

    @Bean(name = "transactionManager")
    public PlatformTransactionManager transactionManager(EntityManagerFactory entityManagerFactory) {
        JpaTransactionManager jpaTransactionManager = new JpaTransactionManager(entityManagerFactory);
        jpaTransactionManager.setDataSource(dataSource());
        jpaTransactionManager.setJpaDialect(jpaDialect());
        return jpaTransactionManager;
    }

    @Bean(name = "persistenceExceptionTranslation")
    public PersistenceExceptionTranslationPostProcessor exceptionTranslation() {
        return new PersistenceExceptionTranslationPostProcessor();
    }

    public Properties jpaProperties() {
        Properties properties = new Properties();
        properties.setProperty("hibernate.hbm2ddl.auto", environment.getProperty("hibernate.hbm2ddl.auto"));
        properties.setProperty("hibernate.dialect", environment.getProperty("hibernate.dialect"));
        properties.setProperty("hibernate.show_sql", environment.getProperty("hibernate.show_sql"));
        properties.setProperty("hibernate.format_sql", environment.getProperty("hibernate.format_sql"));
        properties.setProperty("hibernate.connection.charSet", environment.getProperty("hibernate.connection.charSet"));
        properties.setProperty("hibernate.cache.use_second_level_cache", environment.getProperty("hibernate.cache.use_second_level_cache"));
        properties.setProperty("hibernate.cache.use_query_cache", environment.getProperty("hibernate.cache.use_query_cache"));
        properties.setProperty("hibernate.cache.use_structured_entries", environment.getProperty("hibernate.cache.use_structured_entries"));
        properties.setProperty("hibernate.generate_statistics", environment.getProperty("hibernate.generate_statistics"));
        return properties;
    }
}

作为参考，这里是我几个月前使用的XML配置

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:context="http://www.springframework.org/schema/context"
       xmlns:jee="http://www.springframework.org/schema/jee"
       xmlns:tx="http://www.springframework.org/schema/tx" xmlns:jpa="http://www.springframework.org/schema/data/jpa"
       xsi:schemaLocation="http://www.springframework.org/schema/jee http://www.springframework.org/schema/jee/spring-jee-4.1.xsd
        http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
        http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-4.1.xsd
        http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.1.xsd
        http://www.springframework.org/schema/data/jpa http://www.springframework.org/schema/data/jpa/spring-jpa.xsd">

    <context:annotation-config />

    <jpa:repositories base-package="net.jkratz.bloodpressure.api.repository" />

    <jee:jndi-lookup jndi-name="jdbc/BloodPressureDB" id="dataSource" expected-type="javax.sql.DataSource" />

    <bean id="entityManagerFactory" class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean">
        <property name="persistenceUnitName" value="BPPersistenceUnit" />
        <property name="dataSource" ref="dataSource" />
        <property name="jpaVendorAdapter" ref="jpaVendorAdapter" />
        <property name="jpaDialect" ref="jpaDialect" />
        <property name="packagesToScan">
            <list>
                <value>net.jkratz.bloodpressure.api.model</value>
            </list>
        </property>
        <property name="jpaProperties">
            <props>
                <prop key="hibernate.dialect">${hibernate.dialect}</prop>
                <prop key="hibernate.hbm2ddl.auto">${hibernate.hbm2ddl.auto}</prop>
                <prop key="hibernate.show_sql">${hibernate.show_sql}</prop>
                <prop key="hibernate.format_sql">${hibernate.format_sql}</prop>
                <prop key="hibernate.connection.charSet">${hibernate.connection.charSet}</prop>
            </props>
        </property>
    </bean>

    <bean id="jpaVendorAdapter" class="org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter">
        <property name="database" value="${jpa.vendor.database}" />
        <property name="showSql" value="${jpa.vendor.showSql}"/>
        <property name="generateDdl" value="${jpa.vendor.generateDdl}"/>
        <property name="databasePlatform" value="${jpa.vendor.databasePlatform}"/>
    </bean>

    <bean id="jpaDialect" class="org.springframework.orm.jpa.vendor.HibernateJpaDialect" />

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

    <tx:annotation-driven transaction-manager="transactionManager" />

</beans>

net.jkratz.bloodpressure.api.model
${hibernate.dial}
${hibernate.hbm2ddl.auto}
${hibernate.show_sql}
${hibernate.format_sql}
${hibernate.connection.charSet}

来自文档：

如果是基于Spring的扫描，则不需要persistence.xml；全部的 您需要做的是指定要在此处搜索的基本包

因此，尝试将bean

entityManagerFactory

更改为：

@Bean(name = "entityManagerFactory")
public LocalContainerEntityManagerFactoryBean entityManagerFactory() {
    LocalContainerEntityManagerFactoryBean entityManagerFactory = new LocalContainerEntityManagerFactoryBean();
    entityManagerFactory.setDataSource(dataSource());
    entityManagerFactory.setPersistenceUnitName("postgres");
    entityManagerFactory.setJpaProperties(jpaProperties());
    entityManagerFactory.setJpaVendorAdapter(jpaVendorAdapter());
    entityManagerFactory.setJpaDialect(jpaDialect());
    entityManagerFactory.setPackagesToScan("net.jkratz.bloodpressure.api.model");
    return entityManagerFactory;
}

---

在您的

entityManagerFactory

bean中，您是否尝试设置要扫描的包？检查您的容器类路径中是否有Mysql连接器。啊，是的，我认为@EnableJpaRepositories可以处理这个问题。不，

@EnableJpaRepositories

相当于XML的

jpa:repositories

。