如何为Spring Batch项目中的每个步骤创建自定义ItemReader

public class MyItemReader implements ItemReader<String> {

    private List<String> data;
    private int index;

    public MyItemReader(List<String> data) {
        this.data = data;
        this.index = 0;
    }

    @Override
    public String read() {
        if (index < data.size()) {
            return data.get(index++);
        } else {
            return null;
        }
    }

    @Override
    public void open(ExecutionContext executionContext) throws ItemStreamException {
        // 打开资源，例如打开数据库连接或打开文件
    }

    @Override
    public void update(ExecutionContext executionContext) throws ItemStreamException {
        // 更新读取器的状态
    }

    @Override
    public void close() throws ItemStreamException {
        // 关闭资源，例如关闭数据库连接或关闭文件
    }
}

@Configuration
@EnableBatchProcessing
public class BatchConfig {

    @Autowired
    private JobBuilderFactory jobBuilderFactory;

    @Autowired
    private StepBuilderFactory stepBuilderFactory;

    @Bean
    public ItemReader<String> myItemReader() {
        List<String> data = Arrays.asList("data1", "data2", "data3");
        return new MyItemReader(data);
    }

    @Bean
    public Step myStep(ItemReader<String> myItemReader) {
        return stepBuilderFactory.get("myStep")
                .<String, String>chunk(1)
                .reader(myItemReader)
                .processor(...)
                .writer(...)
                .build();
    }

    @Bean
    public Job myJob(Step myStep) {
        return jobBuilderFactory.get("myJob")
                .start(myStep)
                .build();
    }
}