How to rename file in MFT

khalil — Fri, 01 Sep 2023 22:33:26 +0000

In MFT, when file is moved from source to transfer, we can rename the file.

This will be useful in scenarios when the file name is different than what is expected

Sometime during decryption the extension is lost, we can add a different extension

Sometimes we have to append a source to handle files from different sources differently

We can use RenameRegExp to rename the file

This uses same method as java replace. The input is Regular expression

Common use cases and examples

to completely rename the file –

String sourceRegExp = "([A-Za-z0-9_]+)([A-Za-z0-9.]*)";
String targetRegExp = "input_file.csv";

Input	Output
ABC_SOME_BIG_FILE_NAME.csv	input_file.csv
ABC_SOME_OTHER_FILE_NAME.csv	input_file.csv
SOME_FILE_NAME_WITHOUT_EXTENSION	input_file.csv

To completely change the extension

String sourceRegExp = "([A-Za-z0-9_]+)([A-Za-z0-9.]*)";
String targetRegExp = "$1.csv";

Input	Output
some_data_1.txt	some_data_1.csv
some_data_2.dat	some_data_2.csv
some_data_3.	some_data_3.csv
some_data_4.txt.pgp	some_data_4.csv
some_data_5.txt.gpg	some_data_5.csv
some_data_6.csv	some_data_6.csv
some_data_7	some_data_7.csv

To add a prefix to the file name.

String sourceRegExp = "([A-Za-z0-9_.]+)";
String targetRegExp = "source_$1";

Input	Output
some_data_1.txt	source_some_data_1.txt
some_data_2.dat	source_some_data_2.dat
some_data_3.	source_some_data_3.
some_data_4.txt.pgp	source_some_data_4.txt.pgp
some_data_5.txt.gpg	source_some_data_5.txt.gpg
some_data_6.csv	source_some_data_6.csv
some_data_7	source_some_data_7

Sample Java code to test regular expression if the input / output is as expected:

public class RenameString {
    public static void main(String[] args){

        TestCase[] testCases  = new TestCase[7];
      
        testCases[0] = new TestCase("some_data.txt", "some_data.csv");
        testCases[1] = new TestCase("some_data.dat", "some_data.csv");
        testCases[2] = new TestCase("some_data.", "some_data.csv");
        testCases[3] = new TestCase("some_data.txt.pgp", "some_data.csv");
        testCases[4] = new TestCase("some_data.txt.gpg", "some_data.csv");
        testCases[5] = new TestCase("some_data.csv", "some_data.csv");
        testCases[6] = new TestCase("some_data", "some_data.csv");
    
        for ( TestCase t : testCases) {
            String output = renameFileNameExtension(t.inputStr);

            System.out.print(t.inputStr + " --- " + t.expectedOutputStr + " --- " + output + " --- " );

            if ( output.equals(t.expectedOutputStr) ) {
                System.out.println("success");
            }
            else {
                System.out.println("failed");
            }
        }
    }

    public static String renameFileNameExtension(String inputStr) {
        
        String sourceRegExp = "([A-Za-z0-9_]+)([A-Za-z0-9.]*)";
        String targetRegExp = "$1.csv";

        String output = inputStr.replaceAll(sourceRegExp, targetRegExp);

        return output;
    }

}

class TestCase {
    String inputStr;
    String expectedOutputStr;

    TestCase(String inputStr, String expectedOutputStr){
        this.inputStr = inputStr;
        this.expectedOutputStr = expectedOutputStr;
    }
}

You can test Regular expression using this website https://regex101.com/ and selecting Java language.