Ralph’s TechBlog

Some work has been spent over the last weeks to upgrade the stable CSV Utility Package. Of course, the new version contains all the useful existing functionality. The most beneficial improvement is the introduction of ExcelReader and ExcelWriter classes that behave like the CSV pendants. This means that you do not have to care about the underlying output format when you want to read or write table-structured data. The most important changes are:

• Introduction of a TableReader and TableWriter interface
• Introduction of Excel implementation
• Aligning CSV and Excel implementations to these interfaces
• Introduction of a Factory class in order to select correct implementation (CSV or Excel)

The Beta version still requires some work in terms of documentation and code beautifying. However, the CSV part is already frozen and you can use it to upgrade your existing projects to the new utility version. The Excel part still faces some changes while improving usability.

Please be aware also that Java package structure needed to be changed to integrate the new classes and interfaces. Additionally, new 3rd party libraries were integrated (Apache POI and JavaBeans Activation).

Download the Beta Version or browse the existing API Documentation. Bugs and/or enhancements can be requested via Bugzilla.

I made some fixes and enhancements to the CSV Utility Package:

• Bug #9: Spaces before and after a value are treated correctly now
• Enhancement #10: CSVReader forwards comment lines to callback objects
• Enhancement #11: A test script was integrated to check major features
• New Class: CSVUtils offers methods for copying JDBC results and JTable data to CSVWriters

You can download the latest release here.

A new update of my CSV Utility Package was released. It contains some fixes and enhancements:

• Build system creates tar archive
• Fixed Bug #2: NullPointerException in CSVReader class
• Fixed Bug #4: Multiline values fail when a line looks like a comment
• Enhancement #7: Excel Fix: first column of first row must not start with “ID”
• Enhancement #8: Add row and column count

You can download the latest release here.

I decided recently to publish my very simple utility classes for reading and writing CSV files. The main project page is now available. The package, published under the GNU Lesser General Public License, allows you to easily integrate CSV functionality into your application. The utilities can be configured to use different column delimiter and separator characters in case you need to adopt some other versions of CSV. The default configuration conforms to the Excel style of CSV.

Since this CSV package uses streams, you are able to read from any stream. And, of course, you can write to any stream. You could even synchronize in your application by applying the reader/writer synchronization described in one of my artices.

You can download the latest stable release at the main project page.

Here is a short example on reading a CSV file using the CSVReader class:

java.io.File f = new java.io.File("csv-test.csv");
csv.CSVReader in = new csv.CSVReader(new java.io.FileReader(f));
while (in.hasNext()) {
    String columns[] = in.next();
    // Do something here
}
in.close();

Please note that the CSVReader class actually implements the Iterator interface.

Writing a CSV file is even easier. Just create an instance of the CSVWriter class and pass it your rows:

java.io.File f = new java.io.File("csv-test.csv");
CSVWriter out = new CSVWriter(new java.io.FileWriter(f));
out.printRow(new String[] { "0:0", "0:1", "0:2" });
out.printRow(new String[] { "1:0", "1:1", "1:2" });
out.close();

Documentation

The API documentation tells you all details and configuration parameters that you can use to control the behaviour of the reader and writer classes.