Java Spring 批处理 - 资源文件未注入到 tasklet

Question

我正在执行 Spring 批处理第 1 章中的 java 示例。在此示例中，tasket 解压缩 zip 文件。 tasklet 接收 zip 文件路径作为作业参数。 我实现了一个运行作业并传递参数的测试方法。

@StepScope
@Component
public class DecompressTasklet implements Tasklet {

    private static final Logger LOGGER = LogManager.getLogger(DecompressTasklet.class);

    @Value("#{jobParameters['inputResource']}")
    private Resource inputResource;

    @Value("#{jobParameters['targetDirectory']}")
    private String targetDirectory;

    @Value("#{jobParameters['targetFile']}")
    private String targetFile;

    @Override
    public RepeatStatus execute(StepContribution contribution, ChunkContext chunkContext) throws Exception {
        //code here
    }
}   

@Configuration
public class DescompressStep {

    @Autowired
    private StepBuilderFactory stepBuilderFactory;

    @Autowired
    private DecompressTasklet decompressTasklet;

    @Bean
    public Step stepDescompress() {
        return stepBuilderFactory
                .get(DescompressStep.class.getSimpleName())
                .tasklet(decompressTasklet)
                .build();

    }
}

@EnableBatchProcessing
@Configuration
public class ImportProductsJob {

    @Autowired
    private DescompressStep descompressStep;

    @Autowired
    private ReadWriteProductStep readWriteProductStep;

    @Bean
    public Job job(JobBuilderFactory jobBuilderFactory) {

        return jobBuilderFactory
                .get("importProductsJob")
                .start(descompressStep.stepDescompress())
                .next(readWriteProductStep.stepReaderWriter())
                .incrementer(new RunIdIncrementer())
                .build();
    }


}

下面是运行作业的测试代码

@RunWith(SpringRunner.class)
@SpringBootTest
@SpringBatchTest
@AutoConfigureTestDatabase
public class ImportProductsIntegrationTest {

    @Autowired
    private JobRepositoryTestUtils jobRepositoryTestUtils;  

    @Autowired
    private JobLauncherTestUtils jobLauncherTestUtils;  

    @After
    public void cleanUp() {
        jobRepositoryTestUtils.removeJobExecutions();
    }

    @Test
    public void importProducts() throws Exception {
        jobLauncherTestUtils.launchJob(defaultJobParameters());
    }

    private JobParameters defaultJobParameters() {
        JobParametersBuilder paramsBuilder = new JobParametersBuilder();
        paramsBuilder.addString("inputResource", "classpath:input/products.zip");
        paramsBuilder.addString("targetDirectory", "./target/importproductsbatch/");
        paramsBuilder.addString("targetFile", "products.txt");
        paramsBuilder.addLong("timestamp", System.currentTimeMillis());
        return paramsBuilder.toJobParameters();
   }

}

products.zip 文件在 src/main/resources/input 问题是运行测试时出现错误

java.lang.NullPointerException: null
    at com.springbatch.inaction.ch01.DecompressTasklet.execute(DecompressTasklet.java:62) ~[classes/:na]

我验证了 inputResource 属性是 null。 为什么会出现这个错误？

Answer 1

在你的工作定义中，你有：

@Bean
public Job job(JobBuilderFactory jobBuilderFactory) {

    return jobBuilderFactory
            .get("importProductsJob")
            .start(descompressStep.stepDescompress())
            .next(readWriteProductStep.stepReaderWriter())
            .incrementer(new RunIdIncrementer())
            .build();
}

您通过步骤start和next方法的方式不正确（我什至不知道这将如何编译）。 您可以做的是导入步骤配置类并将这两个步骤都注入到您的作业定义中。 就像是：

@EnableBatchProcessing
@Configuration
@Import({DescompressStep.class, ReadWriteProductStep.class})
public class ImportProductsJob {

    @Bean
    public Job job(JobBuilderFactory jobBuilderFactory,
                   Step stepDescompress, Step stepReaderWriter) {

        return jobBuilderFactory
                .get("importProductsJob")
                .start(stepDescompress)
                .next(stepReaderWriter)
                .incrementer(new RunIdIncrementer())
                .build();
    }

}