我正在使用Spring Boot项目进行Spring
Batch。我的问题是，当我使用HibernateItemWriter时，为什么需要LocalSessionFactoryBean的HibernateTransactionManager和SessionFactory？

应用程序

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

import org.hibernate.SessionFactory;
import org.springframework.batch.core.configuration.annotation.EnableBatchProcessing;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.annotation.Bean;
import org.springframework.orm.hibernate5.HibernateTransactionManager;
import org.springframework.orm.hibernate5.LocalSessionFactoryBuilder;
import org.springframework.transaction.PlatformTransactionManager;

@SpringBootApplication
@EnableBatchProcessing
public class Application {

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

@Bean
public PlatformTransactionManager transactionManager() {
    HibernateTransactionManager transactionManager = new HibernateTransactionManager();
    transactionManager.setSessionFactory(sessionFactory(null));
    return transactionManager;
}

@Bean
public SessionFactory sessionFactory(DataSource datasource) {
    Properties properties = new Properties();
    properties.setProperty("hibernate.show_sql", "true");
    properties.setProperty("hibernate.dialect", "org.hibernate.dialect.HSQLDialect");

    return new LocalSessionFactoryBuilder(datasource).scanPackages("hello")
             .addProperties(properties)
            .buildSessionFactory();
}
}

BatchConfiguration.java

import org.hibernate.SessionFactory;
import org.springframework.batch.core.Step;
import org.springframework.batch.core.configuration.annotation.JobBuilderFactory;
import org.springframework.batch.core.configuration.annotation.StepBuilderFactory;
import org.springframework.batch.core.configuration.annotation.StepScope;
import org.springframework.batch.item.ItemWriter;
import org.springframework.batch.item.database.HibernateItemWriter;
import org.springframework.batch.item.file.FlatFileItemWriter;
import org.springframework.batch.item.file.transform.BeanWrapperFieldExtractor;
import 
org.springframework.batch.item.file.transform.DelimitedLineAggregator;
import org.springframework.batch.item.file.transform.FieldExtractor;
import org.springframework.batch.item.file.transform.LineAggregator;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.core.io.FileSystemResource;
import org.springframework.transaction.PlatformTransactionManager;
import org.springframework.web.client.RestTemplate;

@Configuration
public class BatchConfiguration {

@Autowired
public JobBuilderFactory jobBuilderFactory;

@Autowired
public StepBuilderFactory stepBuilderFactory;

@Autowired
public RestTemplate restTemplate;


@Autowired
public PlatformTransactionManager tManager;

@Value("${file.name}")
public String fileName;


@Bean
@StepScope
public RestItemReader reader2() {
    return new RestItemReader(restTemplate);
}

@Bean
public PersonItemProcessor processor() {
    return new PersonItemProcessor();
}

@Bean
public HibernateItemWriter<Person> hibernateWriter(SessionFactory emf) {
    HibernateItemWriter<Person> writer = new HibernateItemWriter<>();
    writer.setSessionFactory(emf);
    return writer;
}


@Bean
public Step step1() {
    return stepBuilderFactory.get("step1")
            .transactionManager(tManager)
        .<KarvyFundInfoModel, Person> chunk(2)
        .reader(reader2())
        .processor(new PersonItemProcessor())
        .writer(hibernateWriter(null))
        .build();
}
}

这是因为如果我不包含它，并通过使用以下代码从EntityManagerFactory获取SessionFactory的原因

EntityManagerFactory.unwarp(SessionFactory.class);

我将收到“没有正在进行的交易”错误。但是，当我使用JpaItemWriter时，情况并非如此。

但是基于我对Spring Batch的理解，在块处理中，已经提供了默认的事务管理器。

为了使用HibernateItemWriter，是否必须从LocalSessionFactoryBean（来自hibernate）提供HibernateTransactionManager和SessionFactory？

而且，JpaItemWriter和HibernateItemWriter之间的主要区别是什么？我已经做过关于这两个方面的研究，Jpa是关于如何通过使用批注方式指定实体等的规范，而hibernate是Jpa的实现之一。不过，我对此并不十分清楚。hibernate是否比默认的jpa具有更多功能？例如SearchCriteria等？