csvtool

A basic utlity meant to perform operations on multiple CSV files, such as merging, diff, and reformatting. This is meant to be used as a replacement for things such as BATCH files, and Powershell for large CSV files; and can execute much faster. Only requires Java 21+ to be installed.

Most functions use a particular 'Operation' (aka mode of execution) per a task; and this needs to always be the first run paremeter. See the --help menu for more information on use; and refer to the example / documentation under the Reformatting JSON config file generated via the --header-save Operation. There are several 'CSVRemap' functions available that can be used.

Valid Operations:

• --help - Help system. Use --help --operation for more details, optional config settings, and typical syntax used for each operation.
• --test - A simple test routine to make a copy of an existing CSV file using it's internal mechanisms.
• --merge - Merge two CSV files' data assuming that the headers match.
• --diff - Compare two CSV files' data and output a DIFF CSV, assuming that the headers match.
• --header-save - Saves the Headers of a pair of CSV files (Input, Output) to a JSON Headers config file.
• --reformat - Performs a CSV reformat (Input / Output) based on the saved JSON Headers configuration; utilizing the CSV Remap system as outlined in the JSON Config examples. This method can only match or Shrink the size of the Input CSV Headers.

Building manually:

• ./gradlew shadowJar - Builds the full JAR file with all of it's dependancies.