Question

我特别对Spring和Spring-Batch很新。我仍然设法安装 Spring Batch-Admin 。我添加了自定义作业和 Hibernate / JPA 来保持持久性。

一切都按预期工作，直到第一个块应该持久化的程度。然后我收到以下错误消息：

org.springframework.transaction.CannotCreateTransactionException: 
      Could not open JPA  EntityManager for transaction;

nested exception is java.lang.IllegalStateException: Already value
      [org.springframework.jdbc.datasource.ConnectionHolder@60d31437] 
      for key [org.springframework.jdbc.datasource.DriverManagerDataSource@12da4b19] 
      bound to thread [jobLauncherTaskExecutor-1]

这是完整的堆栈跟踪：

org.springframework.transaction.CannotCreateTransactionException: Could not open JPA  EntityManager for transaction; nested exception is java.lang.IllegalStateException: Already value [org.springframework.jdbc.datasource.ConnectionHolder@43f9e588] for key [org.springframework.jdbc.datasource.DriverManagerDataSource@84f171a] bound to thread [jobLauncherTaskExecutor-1]
     at org.springframework.orm.jpa.JpaTransactionManager.doBegin(JpaTransactionManager.java:427)
     at org.springframework.transaction.support.AbstractPlatformTransactionManager.getTransaction(AbstractPlatformTransactionManager.java:371)
     at org.springframework.transaction.interceptor.TransactionAspectSupport.createTransactionIfNecessary(TransactionAspectSupport.java:335)
     at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:105)
     at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:172)
     at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:202)
     at com.sun.proxy.$Proxy41.saveIfUnique(Unknown Source)
     at com.qompa.batch.ArticleItemWriter.write(ArticleItemWriter.java:28)
     at org.springframework.batch.core.step.item.SimpleChunkProcessor.writeItems(SimpleChunkProcessor.java:171)
     at org.springframework.batch.core.step.item.SimpleChunkProcessor.doWrite(SimpleChunkProcessor.java:150)
     at org.springframework.batch.core.step.item.FaultTolerantChunkProcessor$3.doWithRetry(FaultTolerantChunkProcessor.java:313)
     at org.springframework.batch.retry.support.RetryTemplate.doExecute(RetryTemplate.java:240)
     at org.springframework.batch.retry.support.RetryTemplate.execute(RetryTemplate.java:187)
     at org.springframework.batch.core.step.item.BatchRetryTemplate.execute(BatchRetryTemplate.java:213)
     at org.springframework.batch.core.step.item.FaultTolerantChunkProcessor.write(FaultTolerantChunkProcessor.java:402)
     at org.springframework.batch.core.step.item.SimpleChunkProcessor.process(SimpleChunkProcessor.java:194)
     at org.springframework.batch.core.step.item.ChunkOrientedTasklet.execute(ChunkOrientedTasklet.java:74)
     at org.springframework.batch.core.step.tasklet.TaskletStep$ChunkTransactionCallback.doInTransaction(TaskletStep.java:386)
     at org.springframework.transaction.support.TransactionTemplate.execute(TransactionTemplate.java:130)
     at org.springframework.batch.core.step.tasklet.TaskletStep$2.doInChunkContext(TaskletStep.java:264)
     at org.springframework.batch.core.scope.context.StepContextRepeatCallback.doInIteration(StepContextRepeatCallback.java:76)
     at org.springframework.batch.repeat.support.RepeatTemplate.getNextResult(RepeatTemplate.java:367)
     at org.springframework.batch.repeat.support.RepeatTemplate.executeInternal(RepeatTemplate.java:214)
     at org.springframework.batch.repeat.support.RepeatTemplate.iterate(RepeatTemplate.java:143)
     at org.springframework.batch.core.step.tasklet.TaskletStep.doExecute(TaskletStep.java:250)
     at org.springframework.batch.core.step.AbstractStep.execute(AbstractStep.java:195)
     at org.springframework.batch.core.job.SimpleStepHandler.handleStep(SimpleStepHandler.java:135)
     at org.springframework.batch.core.job.flow.JobFlowExecutor.executeStep(JobFlowExecutor.java:61)
     at org.springframework.batch.core.job.flow.support.state.StepState.handle(StepState.java:60)
     at org.springframework.batch.core.job.flow.support.SimpleFlow.resume(SimpleFlow.java:144)
     at org.springframework.batch.core.job.flow.support.SimpleFlow.start(SimpleFlow.java:124)
     at org.springframework.batch.core.job.flow.FlowJob.doExecute(FlowJob.java:135)
     at org.springframework.batch.core.job.AbstractJob.execute(AbstractJob.java:281)
     at org.springframework.batch.core.launch.support.SimpleJobLauncher$1.run(SimpleJobLauncher.java:120)
     at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
     at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
     at java.lang.Thread.run(Thread.java:724)
Caused by: java.lang.IllegalStateException: Already value [org.springframework.jdbc.datasource.ConnectionHolder@43f9e588] for key [org.springframework.jdbc.datasource.DriverManagerDataSource@84f171a] bound to thread [jobLauncherTaskExecutor-1]
     at org.springframework.transaction.support.TransactionSynchronizationManager.bindResource(TransactionSynchronizationManager.java:189)
     at org.springframework.orm.jpa.JpaTransactionManager.doBegin(JpaTransactionManager.java:402)
... 36 more

同一个Job在独立应用程序中执行正常。该问题仅发生在Spring-Batch-Admin环境中。您可以在下面看到项目结构和依赖项：

enter image description here

这是覆盖/扩展Batch-Admin配置的app-context.xml：

<?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:batch="http://www.springframework.org/schema/batch"
    xmlns:context="http://www.springframework.org/schema/context"
    xmlns:task="http://www.springframework.org/schema/task" xmlns:jdbc="http://www.springframework.org/schema/jdbc"
    xmlns:tx="http://www.springframework.org/schema/tx"
    xsi:schemaLocation="http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-3.0.xsd
        http://www.springframework.org/schema/batch http://www.springframework.org/schema/batch/spring-batch-2.1.xsd
        http://www.springframework.org/schema/jdbc http://www.springframework.org/schema/jdbc/spring-jdbc-3.0.xsd
        http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
        http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.0.xsd
        http://www.springframework.org/schema/task http://www.springframework.org/schema/task/spring-task-3.2.xsd">

    <context:component-scan base-package="com.company.batch" />

    <context:property-placeholder location="classpath:batch.properties" />

    <import resource="classpath:/META-INF/spring/batch/jobs/article-job.xml" />

    <bean id="dataSource"
        class="org.springframework.jdbc.datasource.DriverManagerDataSource">
        <property name="driverClassName" value="${batch.jdbc.driver}" />
        <property name="url" value="${batch.jdbc.url}" />
        <property name="username" value="${batch.jdbc.user}" />
        <property name="password" value="${batch.jdbc.password}" />
    </bean>

    <bean id="jdbcTemplate" class="org.springframework.jdbc.core.JdbcTemplate">
        <property name="dataSource" ref="dataSource"></property>
    </bean>

    <bean id="entityManagerFactory"
        class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean">
        <property name="dataSource" ref="dataSource" />
        <property name="packagesToScan" value="com.qompa.batch" />
        <property name="jpaVendorAdapter">
            <bean class="org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter">
                <property name="database" value="POSTGRESQL"></property>
                <property name="showSql" value="true" />
                <property name="generateDdl" value="false" />
                <property name="databasePlatform" value="com.company.utils.persistence.CustomPGDialect" />
            </bean>
        </property>
        <property name="jpaProperties">
            <props>
                <prop key="hibernate.hbm2ddl.auto"></prop>
            </props>
        </property>
    </bean>

    <bean id="txManager" class="org.springframework.orm.jpa.JpaTransactionManager">
        <property name="entityManagerFactory" ref="entityManagerFactory" />
    </bean>
    <tx:annotation-driven transaction-manager="txManager" />

    <!-- schedule tasks -->
    <task:scheduled-tasks>
        <task:scheduled ref="articleRetrieval" method="run"
            cron="0 0 */4 * * *" />
        <task:scheduled ref="articleConversion" method="run"
            cron="0 15 */4 * * *" />
    </task:scheduled-tasks>
</beans>

到目前为止我所理解的是它与jobLauncherTaskExecutor bean引用的ThreadPoolTaskExecutor有关。它似乎处理同时运行作业的连接池 ...但说实话，我不知道如何更改我的配置以使这些工作正常。

[编辑]：我甚至不确定它是否是未提及的ThreadPoolTaskExecutor。但它似乎是TaskExecutor接口的实现。

如果有人遇到类似的问题，或者建议如何以可以为我的持久性方法创建事务的方式配置我的应用程序：请给我一个提示！

Answer 1

错误来自JpaTransactionManager第403行：

TransactionSynchronizationManager.bindResource(getDataSource(), conHolder);

错误意味着事务管理器正在尝试将数据源（而不是实体管理器）绑定到线程，但数据源已经存在并且这是意外的。

请注意，事务管理器尚未启动将实体管理器绑定到线程，这将在JpaTransactionManager第416行接下来发生：

有两种可能的解释：

某人（另一个事务管理器？）是在事务管理器之前将数据源添加到线程中，这是意外的。
或者没有人将数据源添加到事务管理器，只是在任务执行结束时，没有人在将线程返回到池之前清除线程，可能是由于错误或未处理的异常。

有一个问题，这种情况是仅在一个执行线程中发生，还是仅在有多个执行线程时才会发生？

要找出问题所在，这些是一些步骤：

使用导致问题的最少线程运行
在TransactionSynchronizationManager.bindResource()中放置一个断点，以查看谁将连接添加到该线程。断点可以是conditional breakpoint，在线程名称上有条件：“jobLauncherTaskExecutor-1”.equals（Thread.currentThread（）。getName（））
在TransactionSynchronizationManager.unbindResource()中放置一个断点，以查看数据源是否未从该线程中绑定。当断点命中时，向下滚动堆栈跟踪并查看导致这种情况的类。

Answer 2

当您有多个交易管理器时，通常会发生这种情况。

一些提示..

当使用注释@EnableBatchProcessing时，Spring Batch会自动注册一个事务管理器，并且您的JpaTransactionManager可能永远不会被使用。如果要更改spring批处理使用的事务管理器，则必须实现BatchConfigurer接口。（https://blog.codecentric.de/en/2013/06/spring-batch-2-2-javaconfig-part-3-profiles-and-environments/）。

您可以按如下方式为tasklet指定事务管理器：

<tasklet transaction-manager="transactionManager">

Answer 3

如果您有2个数据源，建议您阅读：

https://github.com/spring-projects/spring-boot/issues/3012

因此...配置主数据源（对事务管理器的名称很重要）

@Configuration
@EnableJpaRepositories(
        entityManagerFactoryRef = "entityManager",
        transactionManagerRef = "transactionManager",
        basePackages = "a.b.c")
@PropertySource({"classpath:db_persistence.properties"})
@EnableTransactionManagement

和其他数据源：

@Configuration
@EnableJpaRepositories(
        entityManagerFactoryRef = "another_EntityManager",
        transactionManagerRef = "another_transactionManager",
        basePackages = "x.y.z")
@PropertySource({"classpath:db_persistence.properties"})
@EnableTransactionManagement

希望对您有所帮助。

Answer 4

这类问题出现在较旧的Java版本（例如jdk 6或更低版本）中，请将jdk版本升级到7或更高版本。即使我确实也遇到了同样的问题，但是当我将jdk版本更新为7之前，问题就消失了。

Answer 5

return stepBuilderFactory.get("orderStep1").<sourceBean, destBean>chunk(5)
            .reader(reader)
            .processor(batchFileRowProcessor)
            .writer(batchFileRowDataWritter)
            .taskExecutor(taskExecutor)
            .transactionManager(platformTransactionManager)
            .throttleLimit(1).build();

platformTransactionManager是来自数据源配置的合格Bean

Answer 6

我能够通过为JPA实施spring batch配置来解决类似的问题

import javax.annotation.PostConstruct;
import javax.inject.Inject;
import javax.sql.DataSource;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.batch.core.configuration.BatchConfigurationException;
import org.springframework.batch.core.configuration.annotation.BatchConfigurer;
import org.springframework.batch.core.configuration.annotation.JobBuilderFactory;
import org.springframework.batch.core.configuration.annotation.StepBuilderFactory;
import org.springframework.batch.core.explore.JobExplorer;
import org.springframework.batch.core.explore.support.JobExplorerFactoryBean;
import org.springframework.batch.core.explore.support.MapJobExplorerFactoryBean;
import org.springframework.batch.core.launch.JobLauncher;
import org.springframework.batch.core.launch.support.SimpleJobLauncher;
import org.springframework.batch.core.repository.JobRepository;
import org.springframework.batch.core.repository.support.JobRepositoryFactoryBean;
import org.springframework.batch.core.repository.support.MapJobRepositoryFactoryBean;
import org.springframework.batch.support.transaction.ResourcelessTransactionManager;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.core.task.SimpleAsyncTaskExecutor;
import org.springframework.transaction.PlatformTransactionManager;


@Configuration
public class JpaBatchConfigurer implements BatchConfigurer {
    private static final Logger logger = LoggerFactory
            .getLogger(JpaBatchConfigurer.class);

    @Inject 
    private DataSource dataSource;

    @Inject
    private PlatformTransactionManager transactionManager;

    private JobRepository jobRepository;
    private JobLauncher jobLauncher;
    private JobExplorer jobExplorer;


    protected JpaBatchConfigurer() {
    }


    @Override
    @Bean
    public JobRepository getJobRepository() {
        return jobRepository;
    }

    @Override
    public PlatformTransactionManager getTransactionManager() {
        return transactionManager;
    }

    @Override
    @Bean
    public JobLauncher getJobLauncher() {
        return jobLauncher;
    }

    @Override
    @Bean
    public JobExplorer getJobExplorer() {
        return jobExplorer;
    }

    @PostConstruct
    public void initialize() {
        try {
            if (dataSource == null) {
                logger.warn("No datasource was provided...using a Map based JobRepository");

                if (this.transactionManager == null) {
                    this.transactionManager = new ResourcelessTransactionManager();
                }

                MapJobRepositoryFactoryBean jobRepositoryFactory = new MapJobRepositoryFactoryBean(
                        this.transactionManager);
                jobRepositoryFactory.afterPropertiesSet();
                this.jobRepository = jobRepositoryFactory.getObject();

                MapJobExplorerFactoryBean jobExplorerFactory = new MapJobExplorerFactoryBean(
                        jobRepositoryFactory);
                jobExplorerFactory.afterPropertiesSet();
                this.jobExplorer = jobExplorerFactory.getObject();
            } else {
                this.jobRepository = createJobRepository();

                JobExplorerFactoryBean jobExplorerFactoryBean = new JobExplorerFactoryBean();
                jobExplorerFactoryBean.setDataSource(this.dataSource);
                jobExplorerFactoryBean.afterPropertiesSet();
                this.jobExplorer = jobExplorerFactoryBean.getObject();
            }

            this.jobLauncher = createJobLauncher();
        } catch (Exception e) {
            throw new BatchConfigurationException(e);
        }
    }

    private JobLauncher createJobLauncher() throws Exception {
        SimpleJobLauncher jobLauncher = new SimpleJobLauncher();
        jobLauncher.setJobRepository(jobRepository);
        jobLauncher.setTaskExecutor( new SimpleAsyncTaskExecutor());
        jobLauncher.afterPropertiesSet();
        return jobLauncher;
    }

    protected JobRepository createJobRepository() throws Exception {
        JobRepositoryFactoryBean factory = new JobRepositoryFactoryBean();
        factory.setIsolationLevelForCreate("ISOLATION_SERIALIZABLE");
        factory.setDataSource(dataSource);
        factory.setTransactionManager(transactionManager);
        factory.setValidateTransactionState(false);
        factory.afterPropertiesSet();
        return factory.getObject();
    }

    @Bean
    public JobBuilderFactory jobBuilderFactory(JobRepository jobRepository){
        return new JobBuilderFactory(jobRepository);
    }

    @Bean   
    public StepBuilderFactory stepBuilderFactory(JobRepository jobRepository, PlatformTransactionManager transactionManager){
        return new StepBuilderFactory(jobRepository, transactionManager);
    }
}

这是从以下位置复制的：https://github.com/hantsy/spring4-sandbox/blob/master/batch-jpa/src/main/java/com/hantsylabs/example/spring/config/JpaBatchConfigurer.java

无法打开JPA EntityManager进行交易;嵌套异常是java.lang.IllegalStateException

6 个答案: