In the last recipe, the file we read was a CSV file, but we read it line-by-line. That's not optimal. Cascading provides a number of taps— sources of data or sinks to send data to—including one for CSV and other delimited data formats. Cascalog also has some very nice wrappers for several of these taps, but not for the CSV one.
And in truth, creating a wrapper that exposed all the functionality of the delimited text format tap would be complex. There are options for delimiter characters, for quote characters, for including a header row, for the types of the columns, and other things. That's a lot of options, and dispatching to the right method can be tricky.
We won't worry about handling all of the options right here. For this recipe, we will create a simple wrapper around the delimited text file tap that includes some of the more common options for reading CSV files.