Spring Boot JPA：使用不带persistence.xml的条件

Question

我是Spring Boot和JPA的新手，我按照教程学习，直到我尝试使用Criteria（构建复杂的动态查询）为止，一切进展顺利。

首先，这是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>

	<parent>
		<groupId>com.scalian.app</groupId>
		<artifactId>atelier</artifactId>
		<version>0.0.1-SNAPSHOT</version>
	</parent>
	
	<artifactId>ServerModule</artifactId>
	<version>0.0.1-SNAPSHOT</version>
	<packaging>war</packaging>

	<properties>
		<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
		<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
		<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-data-ldap</artifactId>
		</dependency>
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-data-rest</artifactId>
		</dependency>
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-security</artifactId>
		</dependency>
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-jdbc</artifactId>
		</dependency>
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-web</artifactId>
		</dependency>
		<dependency>
			<groupId>org.springframework.session</groupId>
			<artifactId>spring-session-jdbc</artifactId>
		</dependency>
		<dependency>
			<groupId>com.h2database</groupId>
			<artifactId>h2</artifactId>
			<scope>runtime</scope>
		</dependency>
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-devtools</artifactId>
			<scope>runtime</scope>
		</dependency>
		<dependency>
			<groupId>mysql</groupId>
			<artifactId>mysql-connector-java</artifactId>
			<scope>runtime</scope>
		</dependency>
	    <dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-tomcat</artifactId>	
			<scope>provided</scope>
		</dependency> 
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-test</artifactId>
			<scope>test</scope>
		</dependency>
		<dependency>
			<groupId>org.springframework.restdocs</groupId>
			<artifactId>spring-restdocs-mockmvc</artifactId>
			<scope>test</scope>
		</dependency>
		<dependency>
    		<groupId>org.hibernate</groupId>
    		<artifactId>hibernate-entitymanager</artifactId>
    	</dependency>
	</dependencies>



	<build>
		<plugins>
			<plugin>
				<groupId>org.springframework.boot</groupId>
				<artifactId>spring-boot-maven-plugin</artifactId>
			</plugin>
			<plugin>
				<artifactId>maven-resources-plugin</artifactId>
				<executions>
					<execution>
						<id>copy-resources</id>
						<phase>validate</phase>
						<goals>
							<goal>copy-resources</goal>
						</goals>
						<configuration>
							<outputDirectory>${project.build.directory}/classes/resources/</outputDirectory>
							<resources>
								<resource>
									<directory>${project.parent.basedir}/ClientModule/src/main/web/dist/clientapplication/</directory>
								</resource>
							</resources>
						</configuration>
					</execution>
				</executions>
			</plugin>
		</plugins>
	</build>
		
</project>

这是我的主要应用程序类别：

package com.scalian.app.atelier;

import org.springframework.boot.CommandLineRunner;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

import com.scalian.app.atelier.persistence.repositories.EnvironmentCriteriaBuilder;

@SpringBootApplication
public class AtelierApplication implements CommandLineRunner {
 
	
	public static void main(String[] args) {		
		SpringApplication.run(AtelierApplication.class, args);
	}

	@Override
	public void run(String... args) throws Exception {

		EnvironmentCriteriaBuilder environmentCriteriaBuilder = new EnvironmentCriteriaBuilder(); //Error when adding this line :(
		
	}
	
}

这是EnvironmentCriteriaBuilder类：

package com.scalian.app.atelier.persistence.repositories;


import javax.persistence.EntityManager;
import javax.persistence.Persistence;


public class EnvironmentCriteriaBuilder {
		
	public EnvironmentCriteriaBuilder() {
		
		EntityManager entityManager = Persistence.createEntityManagerFactory("atelierPersistenceUnit").createEntityManager();
		entityManager.close();
	}
	
}

这是我制作的配置类：

package com.scalian.app.atelier;


import java.util.Properties;

import javax.sql.DataSource;

import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Primary;
import org.springframework.dao.annotation.PersistenceExceptionTranslationPostProcessor;
import org.springframework.data.jpa.repository.config.EnableJpaRepositories;
import org.springframework.instrument.classloading.ReflectiveLoadTimeWeaver;
import org.springframework.jdbc.datasource.DriverManagerDataSource;
import org.springframework.orm.jpa.JpaTransactionManager;
import org.springframework.orm.jpa.JpaVendorAdapter;
import org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean;
import org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter;
import org.springframework.transaction.PlatformTransactionManager;
import org.springframework.transaction.annotation.EnableTransactionManagement;

@Configuration
@EnableAutoConfiguration
@EnableTransactionManagement
@EnableJpaRepositories(basePackages = "com.scalian.app.atelier.persistence.repositories", entityManagerFactoryRef = "atelierEntityManagerFactory",transactionManagerRef = "atelierTransactionManager")
public class AtelierConfig {
	
	@Bean
	@Primary
	public DataSource firstDataSource() {
		DriverManagerDataSource dataSource = new DriverManagerDataSource();
	    dataSource.setDriverClassName("com.mysql.jdbc.Driver");
	    dataSource.setUrl("jdbc:mysql://localhost:3306/atelier");
	    dataSource.setUsername( "username" );
	    dataSource.setPassword( "userpassword" );
	    return dataSource;
	}


	@Bean
	public DataSource secondDataSource() {
		return null;
	}
	
	@Bean(name="atelierEntityManagerFactory")
	public LocalContainerEntityManagerFactoryBean entityManagerFactory() {
		
      LocalContainerEntityManagerFactoryBean em = new LocalContainerEntityManagerFactoryBean();
      em.setDataSource(firstDataSource()); 
      em.setPersistenceProviderClass(org.hibernate.jpa.HibernatePersistenceProvider.class);
      JpaVendorAdapter vendorAdapter = new HibernateJpaVendorAdapter();
      em.setJpaVendorAdapter(vendorAdapter);
      em.setPackagesToScan("com.scalian.app.atelier.persistence.entities");
      em.setPersistenceUnitName("atelierPersistenceUnit");
      em.setJpaProperties(additionalProperties());
      em.setLoadTimeWeaver(new ReflectiveLoadTimeWeaver());
 
      return em;
  	}

	 @Bean(name="atelierTransactionManager")
	 public PlatformTransactionManager transactionManager(){
		 JpaTransactionManager transactionManager = new JpaTransactionManager();
		 transactionManager.setEntityManagerFactory(entityManagerFactory().getObject());
		 return transactionManager;
	 }
	 
	 @Bean
	  public PersistenceExceptionTranslationPostProcessor exceptionTranslation(){
	      return new PersistenceExceptionTranslationPostProcessor();
	  }

	 
	 
	Properties additionalProperties() {
	       Properties properties = new Properties();
	       properties.setProperty("hibernate.archive.autodetection", "class, hbm");
	       properties.setProperty("hibernate.hbm2ddl.auto", "validate");
	       properties.setProperty("hibernate.show_sql", "true");
	        
	       return properties;
	   }

}

最后这是控制台输出：

  

... 2018-10-05 10：51：25.045信息6972--[restartedMain]   o.s.b.w.embedded.tomcat.TomcatWebServer：Tomcat在端口上启动：   8080（http）具有上下文路径''2018-10-05 10：51：25.049 INFO 6972   --- [restartedMain] c.s.app.atelier.AtelierApplication：在8.022秒内启动AtelierApplication（JVM运行8.589）   2018-10-05 10：51：25.059信息6972--[restartedMain]   o.h.j.b.internal.PersistenceXmlParser：HHH000318：找不到   类路径中的任何META-INF / persistence.xml文件

     

...原因：javax.persistence.PersistenceException：无持久性   名为atelierPersistenceUnit的EntityManager的提供程序...

     

2018-10-05 10：51：25.069信息6972--[restartedMain]   ConfigServletWebServerApplicationContext：关闭   org.springframework.boot.web.servlet.context.AnnotationConfigServletWebServerApplicationContext@44840690：   启动日期[2018年10月5日星期五10:51:17 CEST];语境的根源   层次结构2018-10-05 10：51：25.072信息6972--[restartedMain]   o.s.j.e.a.AnnotationMBeanExporter：取消注册暴露于JMX的对象   关机时关闭bean 2018-10-05 10：51：25.075 INFO 6972 --- [   [restartedMain] j.LocalContainerEntityManagerFactoryBean：关闭JPA   EntityManagerFactory用于持久性单元“ atelierPersistenceUnit”

我看不到出了什么问题。谢谢您的帮助。