Comments on Confessions of a Java Programmer: Writing flat files in Java with Flatworm

Ok I found the prob, it was a misnaming of an elem...

2010-08-06T06:59:29.794-07:00

Ok I found the prob, it was a misnaming of an element.
Error messages are pretty cryptic

I've created a definition of a line/record which c...

2010-08-06T05:08:35.928-07:00

I've created a definition of a line/record which contains elements which are not contiguous (ie where a "end" finishes, the following "start" does not follow). The ConfigurationReader blows up with a null in a NumberFormatException. I assume from the examples that all fields should be contiguous?

Also is Flatworm threadsafe? Can I have multiple threads using the same object or do I need to either synchronize access or have separate FileFormat objects in Thread Specific data (ThreadLocal)?

I am not able to write the result set into multipl...

2010-06-14T00:34:00.186-07:00

I am not able to write the result set into multiple lines.Its coming in a single line.Please suggest.

I am able to write the resultset into a flat file ...

2010-06-14T00:06:22.089-07:00

I am able to write the resultset into a flat file according to the code and config xml given,but the results are coming in one single line instead of multiple lines.
He is mu code:
Statement stmt = conn.createStatement();
ResultSet rs = stmt.executeQuery(query);
while(rs.next()){
client.setFirstName(rs.getString("first_name").toString());
client.setLastName(rs.getString("last_name").toString());
client.setAddress(rs.getString("address").toString());

fileCreator.write("clientData");
}

Seems like a very useful library. But I was wonde...

2010-03-13T04:30:26.563-08:00

Seems like a very useful library.

But I was wondering. What is the advantage of this record identifier?
If it should accept the following as first field on the record

Isn't that easier and readable?

I'm currently using Flatworm for a project. Its w...

2010-02-18T20:08:09.179-08:00

I'm currently using Flatworm for a project. Its working great. However, I am wondering is there a clean way to handle nulls when writing to a file? I am iterating over a large list of customers and may or may not have some information, like phone numbers etc. Is there a way in the xml to set it to handle nulls? For now I have added null checks to my getters (ie. if (null == city) return new String();) but I am wondering if there is a better way? Thanks!

Good to hear Santosh. ;-)

2010-02-18T11:03:51.756-08:00

Good to hear Santosh. ;-)

Thanks for the reply Michael. Soon after I posted ...

2010-02-18T10:30:53.950-08:00

Thanks for the reply Michael. Soon after I posted my question, through trial and error I was able to generate my records in the required format by leaving out the element from the definition.

Santhosh

Also, I forgot to mention, that by specifying this...

2010-02-17T18:17:31.468-08:00

Also, I forgot to mention, that by specifying this value as the default-value in the conversion options, you won't have to put the match string in your XML.

Santosh, Thanks, but I didn't develop Flatworm. ...

2010-02-17T18:05:27.599-08:00

Santosh,

Thanks, but I didn't develop Flatworm. However I have used it extensively and decided to write how to perform some tasks that weren't readily available already.

Are you going to have multiple record types within your file? That is what this identification is for. It is not to identify the data so much as the type of data. Generally within flat files you'll have headers, maybe some batch headers, detail records, etc.

So in order for a record type to be identified, it generally has a static value somewhere within the line. For example, all detail record lines may start with DR.

For a simple example where we're writing out a flat file of employees. We're going to have two record types. A file header and the detail records. The file header is going to give the date the file was created and the number of detail records. The file header always start with FH. So a sample file header may look like this:

FH2010021700002

This file header was created on Feb 17, 2010 and this file contains two detail records.

The detail record contains the employee's first name, last name and employee id. All detail records start with DT.

DTJohn Doe 1234567890
DTBob Smith 0987654321

In this instance, you are assigning the employee IDs on the fly, but you are using DT as the match string so flatworm knows what type of file you are trying to write.

Does this help with what you are doing?

Hi Michael, This is a neat tool. Thanks for deve...

2010-02-17T14:28:15.752-08:00

Hi Michael,
This is a neat tool. Thanks for developing it. I am planning to use this in one of my projects . The one main problem I have with this implementation is the mandatory value for record-ident/match-string element. I would like to populate this through the program. Since I have a variable record ID I prefer not to specify this in the XML. I would like to specify only the record definition. I tried field-start=0 and field-length=0 and no value for match-string element but got a "null" prefix in the output. Do you have any suggestions how to get around this problem.

Thanks
Santhosh

Can you provide a few sample lines of your file?

2010-01-11T16:39:22.370-08:00

Can you provide a few sample lines of your file?

I am using Flatworm to make a fixed-width file. E...

2010-01-08T12:23:04.270-08:00

I am using Flatworm to make a fixed-width file.

Each line in the file is like:
ID(12)... Name(12)... Company(8)... Dept(10)

And the word "ABC" is to be put in Company (for each ID). I don't have it in the bean.

The rest I am getting them from the bean.

How do I do it??? Please suggest.

Thanks.

@Anonymous You can do this by declaring a default...

2009-10-29T07:49:15.284-07:00

@Anonymous

You can do this by declaring a default record type. I don't believe I have posted anything on this, but I can have something up today or tomorrow.

Just comment out the line that declares the DTD as...

2009-10-29T07:43:25.944-07:00

Just comment out the line that declares the DTD as I did in my sample configuration file above.

Sorry, I need a little help with FlatWorm. Where i...

2009-10-29T07:39:34.710-07:00

Sorry, I need a little help with FlatWorm. Where is the dtd file? The url is a resort... And without dtd I have a NoClassDefFoundError..
Thank you,
Matteo

Nice work. Is it possible to not create a record i...

2009-10-28T07:00:50.733-07:00

Nice work. Is it possible to not create a record identifier in the flat file?