Springboot/Spring 批量加载不带分隔符的文件

Springboot/Spring Batch load a file without separator

使用 Springboot/Spring 批处理,我尝试加载一个没有分隔符的文件。

文件示例:

field1field2field3
field1field2field3
field1field2field3

这是我的代码:

@Bean
    public FlatFileItemReader<Person> reader() {

          
          return new FlatFileItemReaderBuilder<Person>() 
                  .name("personItemReader")
                  .resource(new ClassPathResource("people.txt"))
                  .lineTokenizer(new FixedLengthTokenizer()  {{ setNames("firstName", "lastName"); setColumns(new Range(1-6,7-12)); }})
                  .fieldSetMapper(new BeanWrapperFieldSetMapper<Person>() {{ setTargetType(Person.class); }})
                  .build()
                  ; 
    }

但是没用。我有以下错误,我不明白为什么:

Bean instantiation via factory method failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [org.springframework.batch.item.file.FlatFileItemReader]: Factory method 'reader' threw exception; nested exception is java.lang.IllegalArgumentException: Min value must be higher than zero

你能解释一下吗?

您在此处声明的行分词器不正确:

.lineTokenizer(new FixedLengthTokenizer() {{
      setNames("firstName", "lastName");
      setColumns(new Range(1-6,7-12));
 }})

这就好像您指定了 [-5, -5] 的范围。 setColumns 采用 Range 的可变参数,其中每个范围应使用 Range(min, max) 创建。所以在你的情况下它应该是这样的:

.lineTokenizer(new FixedLengthTokenizer()  {{
       setNames("firstName", "lastName");
       setColumns(new Range(1,6), new Range(7,12));
}})