如何在 spring 批次中读取单个项目 reader 中的逗号分隔和管道分隔的 csv 文件

Question

我是小枝批次的新手。我有一个包含多个 csv 文件的文件夹，我已经实现了 MultiResourceItemReader () 来读取这些文件。仅当所有 csv 文件都以管道线（“|”）分隔时，它才有效。

我想使用单个 reader 读取逗号 (",") 分隔的 csv 和管道分隔的 csv。可能吗？如果是的话怎么办？

这是我的代码

@Bean
@StepScope
public MultiResourceItemReader<Person> multiResourceItemReader(@Value("#{jobParameters[x]}") String x,@Value("#{jobParameters[y]}") String y,@Value("#{jobParameters[z]}") String z) {

    Resource[] resourcessss = null;
    ClassLoader cl = this.getClass().getClassLoader();
    ResourcePatternResolver resolver = new PathMatchingResourcePatternResolver(cl);
    try {
        resourcessss = resolver.getResources("file:" + z);
    }catch(Exception e) {

    }
    MultiResourceItemReader<Person> resourceItemReader = new MultiResourceItemReader<Person>();
    resourceItemReader.setResources(resourcessss);
    resourceItemReader.setDelegate(reader());

    return resourceItemReader;
}



@Bean
public FlatFileItemReader<Person> reader() {
    FlatFileItemReader<Person> reader = new FlatFileItemReader<Person>();
    reader.setLineMapper(new DefaultLineMapper() {
        {
            setLineTokenizer(new DelimitedLineTokenizer() {
                {
                    setNames(new String[]{"Id","postCode"});
                }
                {
                    setDelimiter("|");
                }
            });
            setFieldSetMapper(new BeanWrapperFieldSetMapper<Person>() {
                {
                    setTargetType(Person.class);
                }
            });
        }
    });
    return reader;
}

Answer 1

看看PatternMatchingCompositeLineTokenizer。在那里，您可以使用 Pattern 来确定哪些记录被 LineTokenizer 解析。在您的情况下，您将有一个 Pattern 来标识逗号分隔的记录并将它们映射到通过逗号解析的分词器。您还会有一个 Pattern，用于标识由竖线分隔的记录并将这些记录映射到适当的 LineTokenizer。它看起来像这样：

    @Bean
    public LineTokenizer compositeLineTokenizer() throws Exception {
        DelimitedLineTokenizer commaTokenizer = new DelimitedLineTokenizer();

        commaTokenizer.setNames("a", "b", "c");
        commaTokenizer.setDelimiter(",");
        commaTokenizer.afterPropertiesSet();

        DelimitedLineTokenizer pipeTokenizer = new DelimitedLineTokenizer();

        pipeTokenizer.setNames("a", "b", "c");
        pipeTokenizer.setDelimiter("|");

        pipeTokenizer.afterPropertiesSet();

        // I have not tested the patterns here so they may need to be adjusted
        Map<String, LineTokenizer> tokenizers = new HashMap<>(2);
        tokenizers.put("*,*", commaTokenizer);
        tokenizers.put("*|*", pipeTokenizer);

        PatternMatchingCompositeLineTokenizer lineTokenizer = new PatternMatchingCompositeLineTokenizer();

        lineTokenizer.setTokenizers(tokenizers);

        return lineTokenizer;
    }

如何在 spring 批次中读取单个项目 reader 中的逗号分隔和管道分隔的 csv 文件

how to read both comma separated and pipe line separated csv file in a single item reader in spring batch

java

spring

batch-processing

spring-batch