Parsing multi-format & multi line data file in spring batch job - spring

Question

I am writing a spring batch job to process the below mentioned data file and write it into a db.
Sample data file is of this format where I have multiple headers and
each header has a bunch of rows associated with it .
I can have million of records for each header and I can have n number
of headers in a flat file that am processing.My requirement is to
pick a few readers which am concerned .
For all the picked readers I need to pick all the data rows .Each
header and its data format is also different .I can receive either of
these data in my processor and need to write them into my DB.
HDR01
A|41|57|Data1|S|62|Data2|9|N|2017-02-01 18:01:05|2017-02-01 00:00:00
A|41|57|Data1|S|62|Data2|9|N|2017-02-01 18:01:05|2017-02-01 00:00:00
HDR02
A|41|57|Data1|S|62|Data2|9|N|
A|41|57|Data1|S|62|Data2|9|N|
I tried exploring the PatternMatchingCompositeLineMapper where I can
map the different header pattern I have to a tokenizer and
corresponding FieldSetMapper but I need to read the body and not the
header here .
Don't have any footer to Crete a end of line policy of my own as well .
Also tried using AggregateItemReader but don't want to club all the
records of a header before I process them .
Each rows corresponding a header should be processed parallel .
#Bean
public LineMapper myLineMapper() {
PatternMatchingCompositeLineMapper< Domain > mapper = new PatternMatchingCompositeLineMapper<>();
final Map<String, LineTokenizer> tokenizers = new HashMap<String, LineTokenizer>();
tokenizers.put("* HDR01*", new DelimitedLineTokenizer());
tokenizers.put("*HDR02*", new DelimitedLineTokenizer());
tokenizers.put("*", new DelimitedLineTokenizer("|"));
mapper.setTokenizers(tokenizers);
Map<String, FieldSetMapper<VMSFeedStyleInfo>> mappers = new HashMap<String, FieldSetMapper<VMSFeedStyleInfo>>();
try {
mappers.put("* HDR01*", customMapper());
mappers.put("*HDR02*", customMapper());
mappers.put("*", customMapper() );
} catch (Exception e) {
e.printStackTrace();
}
mapper.setFieldSetMappers(mappers);
return mapper;
}
Can somebody help me provide some inputs as to how should I achieve this .