考虑将其中一个 bean 标记为 @Primary，更新使用者以接受多个 bean，或使用 @Qualifier 来识别

Question

我正在使用弹簧批处理启动示例。在我的项目中，到目前为止，我已经开发了两个批处理作业，将来将同时运行大约 10 个批处理作业。

我为第二批作业开发了代码，当我开始运行第二批作业时，我开始收到以下错误。

我心中有以下疑问——

1. 如何仅运行第二批进行开发和单元测试？
2. 如何一次性运行所有批处理作业？

即将出现的错误 -

org.springframework.beans.factory.NoUniqueBeanDefinitionException: No qualifying bean of type 'org.springframework.batch.core.Job' available: expected single matching bean but found 2: exportemployeesJob,exportOrdersJob
at org.springframework.beans.factory.config.DependencyDescriptor.resolveNotUnique(DependencyDescriptor.java:215) ~[spring-beans-5.0.7.RELEASE.jar:5.0.7.RELEASE]
at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1116) ~[spring-beans-5.0.7.RELEASE.jar:5.0.7.RELEASE]
at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1065) ~[spring-beans-5.0.7.RELEASE.jar:5.0.7.RELEASE]
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:584) ~[spring-beans-5.0.7.RELEASE.jar:5.0.7.RELEASE]
at org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:91) ~[spring-beans-5.0.7.RELEASE.jar:5.0.7.RELEASE]
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:373) ~[spring-beans-5.0.7.RELEASE.jar:5.0.7.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1350) ~[spring-beans-5.0.7.RELEASE.jar:5.0.7.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:580) ~[spring-beans-5.0.7.RELEASE.jar:5.0.7.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:503) ~[spring-beans-5.0.7.RELEASE.jar:5.0.7.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:317) ~[spring-beans-5.0.7.RELEASE.jar:5.0.7.RELEASE]
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:222) ~[spring-beans-5.0.7.RELEASE.jar:5.0.7.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:315) ~[spring-beans-5.0.7.RELEASE.jar:5.0.7.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:199) ~[spring-beans-5.0.7.RELEASE.jar:5.0.7.RELEASE]
at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:760) ~[spring-beans-5.0.7.RELEASE.jar:5.0.7.RELEASE]
at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:869) ~[spring-context-5.0.7.RELEASE.jar:5.0.7.RELEASE]
at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:550) ~[spring-context-5.0.7.RELEASE.jar:5.0.7.RELEASE]
at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:759) [spring-boot-2.0.3.RELEASE.jar:2.0.3.RELEASE]
at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:395) [spring-boot-2.0.3.RELEASE.jar:2.0.3.RELEASE]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:327) [spring-boot-2.0.3.RELEASE.jar:2.0.3.RELEASE]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1255) [spring-boot-2.0.3.RELEASE.jar:2.0.3.RELEASE]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1243) [spring-boot-2.0.3.RELEASE.jar:2.0.3.RELEASE]
at com.prateek.SpringBatchClassicDbApplication.main(SpringBatchClassicDbApplication.java:12) [classes/:na]
2018-07-08 21:45:23.396 ERROR 11600 --- [           main] o.s.b.d.LoggingFailureAnalysisReporter   : 
***************************
APPLICATION FAILED TO START
***************************
Description:
Field job in com.prateek.scheduler.EmployeesRunScheduler required a single bean, but 2 were found:
- exportemployeesJob: defined by method 'exportemployeesJob' in class path resource [com/prateek/job/EmployeesJob.class]
- exportOrdersJob: defined by method 'exportOrdersJob' in class path resource [com/prateek/job/OrdersJob.class]

Action:
Consider marking one of the beans as @Primary, updating the consumer to accept multiple beans, or using @Qualifier to identify the bean that should be consumed

订单作业.java

@Configuration
@EnableBatchProcessing
public class OrdersJob {
@Autowired
private JobBuilderFactory jobBuilderFactory;
@Autowired
private StepBuilderFactory stepBuilderFactory;
@Autowired
private DataSource dataSource;
@Bean(destroyMethod="")
public JdbcCursorItemReader<Orders> ordersReader(){
JdbcCursorItemReader<Orders> itemReader = new JdbcCursorItemReader<>();
itemReader.setDataSource(dataSource);
itemReader.setSql("SELECT orderNumber, productName, msrp, priceEach "
+ "FROM products p "
+ "INNER JOIN orderdetails o "
+ "ON p.productcode = o.productcode "
+ "AND p.msrp > o.priceEach ");
//+ "WHERE p.productcode = ? ");
itemReader.setRowMapper(new OrdersRowMapper());
itemReader.setIgnoreWarnings(true);
return itemReader;
}

@Bean(destroyMethod="")
public FlatFileItemWriter<Orders> ordersWriter(){
FlatFileItemWriter<Orders> fileItemWriter = new FlatFileItemWriter<>();
fileItemWriter.setResource(new FileSystemResource("csv/Orders.csv"));
//fileItemWriter.setHeaderCallback(headerCallback());
DelimitedLineAggregator<Orders> lineAggregator = new DelimitedLineAggregator<>();
lineAggregator.setDelimiter(",");
lineAggregator.setFieldExtractor(new PassThroughFieldExtractor<Orders>());
fileItemWriter.setLineAggregator(lineAggregator);
fileItemWriter.setShouldDeleteIfEmpty(true);
return fileItemWriter;
}

// Step Execution
@Bean
public Step step1() {
return stepBuilderFactory.get("step1")
.<Orders, Orders>chunk(10)
.reader(ordersReader())
.writer(ordersWriter())
.build();
}
// Job Execution
@Bean
public Job exportOrdersJob() {
return jobBuilderFactory
.get("exportOrdersJob")
.incrementer(new RunIdIncrementer())
.flow(step1())
.end()
.build();
}
}

员工工作.java

@Configuration
@EnableBatchProcessing
public class EmployeesJob {
public static final String DATE_FORMAT = "dd-MM-yyyy-hh-mm-ssss";
public static final DateFormat formatter = new SimpleDateFormat(DATE_FORMAT);
@Autowired
private JobBuilderFactory jobBuilderFactory;
@Autowired
private StepBuilderFactory stepBuilderFactory;
@Autowired
private DataSource dataSource;
@Bean 
public EmployeesProcessor employeesProcessor() {
return new EmployeesProcessor();
}
@Bean
public EmployeesRunScheduler scheduler() {
return new EmployeesRunScheduler();
}
// This file helps to create CSV column aliases
@Bean
public EmployeesFlatFileWriterCallback headerCallback() {
return new EmployeesFlatFileWriterCallback();
}
@Bean(destroyMethod="")
public JdbcCursorItemReader<Employees> employeesReader(){
JdbcCursorItemReader<Employees> itemReader = new JdbcCursorItemReader<>();
itemReader.setDataSource(dataSource);
itemReader.setSql("SELECT employeeNumber, lastName, firstName, extension, email, officeCode, reportsTo, jobTitle FROM employees ");
itemReader.setRowMapper(new EmployeeRowMapper());
// The fetch size can be controlled from the application.properties 
//itemReader.setFetchSize(200);
return itemReader;
}

@Bean(destroyMethod="")
public FlatFileItemWriter<Employees> employeesWriter(){
FlatFileItemWriter<Employees> fileItemWriter = new FlatFileItemWriter<>();
//fileItemWriter.setResource(new FileSystemResource("csv/employees.csv"));
fileItemWriter.setResource(new FileSystemResource("csv/employees-#{"+ formatter.format(new Date()) +"}.csv"));
fileItemWriter.setHeaderCallback(headerCallback());
BeanWrapperFieldExtractor<Employees> fieldExtractor = new BeanWrapperFieldExtractor<>();
fieldExtractor.setNames(new String[] {"employeeNumber", "lastName", "firstName", "extension", "email", "officeCode", "reportsTo", "jobTitle"});
DelimitedLineAggregator<Employees> lineAggregator = new DelimitedLineAggregator<>();
lineAggregator.setDelimiter(",");
lineAggregator.setFieldExtractor(fieldExtractor);
fileItemWriter.setLineAggregator(lineAggregator);
fileItemWriter.setShouldDeleteIfEmpty(true);
return fileItemWriter;
} 
// Step Execution
@Bean
public Step step1() {
return stepBuilderFactory.get("step1")
.<Employees, Employees>chunk(10)
.reader(employeesReader())
.processor(employeesProcessor())
.writer(employeesWriter())
.build();
}
// Job Execution
@Bean
public Job exportemployeesJob() {
return jobBuilderFactory
.get("employeesJob")
.incrementer(new RunIdIncrementer())
.flow(step1())
.end()
.build();
}
}

Answer 1

如何只运行第二批进行开发和单元测试？

可以将配置文件用于第二个作业，并仅在开发和单元测试中激活此配置文件

如何一次性运行所有批处理作业？

默认情况下，Spring 引导在启动时按顺序执行应用程序上下文中的所有作业(更多详细信息，请参见：https://docs.spring.io/spring-boot/docs/current/reference/html/howto-batch-applications.html(。如果"一次性"是指并行启动所有作业，则可以使用由异步TaskExecutor(例如ThreadPoolTaskExecutor(支持的JobLauncher。更多详情请见：https://docs.spring.io/spring-batch/4.0.x/reference/html/job.html#configuringJobLauncher