Question

这是我的代码，我不知道为什么我的bean MouvementToMapItemProcessor没有注入，它在构造函数中始终为null

@Autowired
    private MouvementToMapItemProcessor mvts;

    private Iterator it;

    public InMemoryMouvementReader() {
        it = mvts.getMouvmentFileRowMap().entrySet().iterator();
    }

这是我的配置类：

@Configuration
@EnableBatchProcessing
public class BatchConfiguration {


    public BatchConfiguration() {
    }


    @Bean
    public ItemReader<MouvementFileRow> mouvementMapReader() {
        return new InMemoryMouvementReader();
    }


    @Bean
    public ItemProcessor<MouvementFileRow, MouvementFileRow> mouvementMapProcessor() {
        return new MouvementToMapItemProcessor();
    }



    @Bean
    public Step generateDemmandeCommunication() {
        return stepBuilderFactory.get("generateDemmandeCommunication")
                .<MouvementFileRow, DemandeCommunication>chunk(10)
                .faultTolerant().skipLimit(Integer.MAX_VALUE).skip(CustomReaderSkipException.class)
                .reader(mouvementMapReader())
                .processor(mouvementProcessor())
                .writer(demandeCommunicationItemWriter())
                .listener(customStepListener())
                .build();
    }

public class InMemoryMouvementReader implements ItemReader<MouvementFileRow> {

    @Autowired
    private MouvementToMapItemProcessor mvts;

    private Iterator it;

    public InMemoryMouvementReader() {
        it = mvts.getMouvmentFileRowMap().entrySet().iterator();
    }

    private void initialize() {
    }

    @Override
    public MouvementFileRow read() throws Exception {
        if (it.hasNext()) {
            return mvts.getMouvmentFileRowMap().get(it.next());
        } else return null;
    }
}

@Component
public class MouvementToMapItemProcessor implements ItemProcessor<MouvementFileRow, MouvementFileRow> {

    private static final Logger log = LoggerFactory.getLogger(MouvementToMapItemProcessor.class);

    private Map<Long, MouvementFileRow> mouvmentFileRowMap;

    public MouvementToMapItemProcessor() {
        mouvmentFileRowMap = new HashMap<Long, MouvementFileRow>();

    }

    @Override
    public MouvementFileRow process(final MouvementFileRow mouvement) throws Exception {
        ........
        return null;
    }

    public Map<Long, MouvementFileRow> getMouvmentFileRowMap() {
        return mouvmentFileRowMap;
    }

我的堆栈跟踪

启动ApplicationContext时出错。要显示自动配置报告，请使用＆＃39; debug＆＃39;重新运行您的应用程序。启用。 11：55：29.139 [restartedMain] ERROR o.s.boot.SpringApplication - 应用程序启动失败 org.springframework.beans.factory.BeanCreationException：创建名为＆＃39; mouvementMapReader＆＃39;的bean时出错。在类路径资源[fr / gouv / justice / spark / fileToBaseBatch / BatchConfiguration.class]中定义：通过工厂方法的Bean实例化失败;嵌套异常是org.springframework.beans.BeanInstantiationException：无法实例化[org.springframework.batch.item.ItemReader]：工厂方法＆mouvementMapReader＆＃39;抛出异常;嵌套异常是java.lang.NullPointerException 在org.springframework.beans.factory.support.ConstructorResolver.instantiateUsingFactoryMethod（ConstructorResolver.java:599）在org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateUsingFactoryMethod（AbstractAutowireCapableBeanFactory.java:1173）在org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance（AbstractAutowireCapableBeanFactory.java:1067）在org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean（AbstractAutowireCapableBeanFactory.java:513）在org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean（AbstractAutowireCapableBeanFactory.java:483） at org.springframework.beans.factory.support.AbstractBeanFactory $ 1.getObject（AbstractBeanFactory.java:306）在org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton（DefaultSingletonBeanRegistry.java:230）在org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean（AbstractBeanFactory.java:302）在org.springframework.beans.factory.support.AbstractBeanFactory.getBean（AbstractBeanFactory.java:197）在org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons（DefaultListableBeanFactory.java:761）在org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization（AbstractApplicationContext.java:867）在org.springframework.context.support.AbstractApplicationContext.refresh（AbstractApplicationContext.java:543）在org.springframework.boot.SpringApplication.refresh（SpringApplication.java:693）在org.springframework.boot.SpringApplication.refreshContext（SpringApplication.java:360）在org.springframework.boot.SpringApplication.run（SpringApplication.java:303）在org.springframework.boot.SpringApplication.run（SpringApplication.java:1118）在org.springframework.boot.SpringApplication.run（SpringApplication.java:1107）在fr.gouv.justice.spark.fileToBaseBatch.Application.main（Application.java:18） at sun.reflect.NativeMethodAccessorImpl.invoke0（Native Method） at sun.reflect.NativeMethodAccessorImpl.invoke（NativeMethodAccessorImpl.java:62） at sun.reflect.DelegatingMethodAccessorImpl.invoke（DelegatingMethodAccessorImpl.java:43） at java.lang.reflect.Method.invoke（Method.java:498）在org.springframework.boot.devtools.restart.RestartLauncher.run（RestartLauncher.java:49）引起：org.springframework.beans.BeanInstantiationException：无法实例化[org.springframework.batch.item.ItemReader]：工厂方法＆mouvementMapReader＆＃39;抛出异常;嵌套异常是java.lang.NullPointerException 在org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate（SimpleInstantiationStrategy.java:189）在org.springframework.beans.factory.support.ConstructorResolver.instantiateUsingFactoryMethod（ConstructorResolver.java:588） ...省略了22个常用帧引起：java.lang.NullPointerException：null at fr.gouv.justice.spark.fileToBaseBatch.readers.InMemoryMouvementReader。（InMemoryMouvementReader.java:19） at fr.gouv.justice.spark.fileToBaseBatch.BatchConfiguration.mouvementMapReader（BatchConfiguration.java:74） at fr.gouv.justice.spark.fileToBaseBatch.BatchConfiguration $$ EnhancerBySpringCGLIB $$ e3e5804e.CGLIB $ mouvementMapReader $ 34（） at fr.gouv.justice.spark.fileToBaseBatch.BatchConfiguration $$ EnhancerBySpringCGLIB $$ e3e5804e $$ FastClassBySpringCGLIB $$ 8f516405.invoke（）在org.springframework.cglib.proxy.MethodProxy.invokeSuper（MethodProxy.java:228） at org.springframework.context.annotation.ConfigurationClassEnhancer $ BeanMethodInterceptor.intercept（ConfigurationClassEnhancer.java:358） at fr.gouv.justice.spark.fileToBaseBatch.BatchConfiguration $$ EnhancerBySpringCGLIB $$ e3e5804e.mouvementMapReader（） at sun.reflect.NativeMethodAccessorImpl.invoke0（Native Method） at sun.reflect.NativeMethodAccessorImpl.invoke（NativeMethodAccessorImpl.java:62） at sun.reflect.DelegatingMethodAccessorImpl.invoke（DelegatingMethodAccessorImpl.java:43） at java.lang.reflect.Method.invoke（Method.java:498）在org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate（SimpleInstantiationStrategy.java:162） ...省略了23个常见帧

Answer 1

你的MouvementToMapItemProcessor在构造之前没有被注入InMemoryMouvementReader，这是导致构造函数失败并出现NullPointerException的原因。请改用构造函数注入：

@Autowired
public InMemoryMouvementReader(MouvementToMapItemProcessor mvts) {
    this.mvts = mvts;
    it = mvts.getMouvmentFileRowMap().entrySet().iterator();
}

和

@Bean
public ItemReader<MouvementFileRow> mouvementMapReader(MouvementToMapItemProcessor mvts) {
    return new InMemoryMouvementReader(mvts);
}

和

@Bean
public Step generateDemmandeCommunication(InMemoryMouvementReader reader, MouvementToMapItemProcessor mvts) {
    return stepBuilderFactory.get("generateDemmandeCommunication")
            .<MouvementFileRow, DemandeCommunication>chunk(10)
            .faultTolerant().skipLimit(Integer.MAX_VALUE).skip(CustomReaderSkipException.class)
            .reader(reader)
            .processor(mvts)
            .writer(demandeCommunicationItemWriter())
            .listener(customStepListener())
            .build();
}

我的bean总是在注入后返回null

1 个答案: