如何通过 java 配置没有 StepExecutionListener 实现的侦听器注册，既没有 StepListenerExecutionSupport 扩展

Question

我正在学习 Spring Batch in Action 一书，我在第 114/115 页找到了 StopListener 示例。如何注册一个既不实现 StepExecutionListener 又不扩展 StepListenerExecutionSupport 的侦听器 class？我没有使用 Spring Xml 配置，所以我必须将 xml 中提供的示例转换为 java 配置。

据书

public class StopListener {
  private StepExecution stepExecution;
  @BeforeStep
  public void beforeStep(
      StepExecution stepExecution) {
    this.stepExecution = stepExecution;
  }
 @AfterRead
  public void afterRead() {
    if(stopConditionsMet()) {
      stepExecution.setTerminateOnly();
    }
  }...

<bean id="stopListener" class="com.manning.sbia.ch04.stop.StopListener" /> 
<batch:job id="importProductsJob">
  <batch:step id="importProductsStep">
    <batch:tasklet>
      <batch:chunk reader="reader" writer="writer" commit-interval="100"/>
      <batch:listeners>
        <batch:listener ref="stopListener" />
      </batch:listeners>
    </batch:tasklet>
  </batch:step>
</batch:job>

正如我所尝试的：

...
       @Bean
       public StepExecutionListener stepListener(){
              return new StopListener(); //obviously, it raises casting issues
       }

       @Bean
       public Step stepA(ItemReader<String> readerA, ItemWriter<String> writerA,
                     StepExecutionListener stepListener) {  
              return stepBuilderFactory.get("stepA").<String, String> chunk(1)
                           .reader(readerA).writer(writerA).allowStartIfComplete(false)
                           .startLimit(1).listener(stepListener).build();
       }

@Component
public class StopListener {
       private StepExecution stepExecution;
       private static final Logger log = LoggerFactory.getLogger(StopListener.class);

       @BeforeStep
       public void beforeStep(StepExecution stepExecution) {
              log.info("StopListener.beforeStep()");
              this.stepExecution = stepExecution;
       }

       @AfterRead
       public void afterRead() {
              if (true) {
                     stepExecution.setTerminateOnly();
              }
       }
}

Answer 1

像这样。

@豆子 public StopListener stepListener(){ return 新的 StopListener()； //显然，它引发了转换问题 }

   @Bean
   public Step stepA(ItemReader<String> readerA, ItemWriter<String> writerA) {  
          return stepBuilderFactory.get("stepA").<String, String> chunk(1)
                       .reader(readerA).writer(writerA).allowStartIfComplete(false)
                       .startLimit(1).listener(stepListener()).build();
   }

listener 方法采用 Object 并检测类型或注释方法。

如何通过 java 配置没有 StepExecutionListener 实现的侦听器注册，既没有 StepListenerExecutionSupport 扩展

how register via java config a listener without StepExecutionListener implementation neither StepListenerExecutionSupport extending

spring

spring-batch

spring-java-config