You can use Java's built-in file I/O classes to read the contents of the file and then parse the contents to check if it is in the expected format.
Here's an example code snippet:
import java.io.File;
import java.io.IOException;
import java.nio.file.Files;
import java.util.List;
public class ValidateFileFormat {
public static void main(String[] args) {
File file = new File("path/to/file.txt");
try {
List<String> lines = Files.readAllLines(file.toPath());
for (String line : lines) {
if (!line.matches("^[0-9]{7}[a-zA-Z ]{7}[0-9]{3}[ ]+[0-9]{4}[ ]+[0-9]{5}[ ]+[a-zA-Z0-9 ]{7}[0-9]{7}$")) {
throw new Exception("Invalid file format: " + line);
}
if (line.substring(7, 10).equals("2000")) {
// Do something with the line that contains "2000"
}
}
System.out.println("File format is valid.");
} catch (IOException e) {
e.printStackTrace();
} catch (Exception e) {
e.printStackTrace();
}
}
}
This code reads the contents of the file line by line, and then checks each line against a regular expression to see if it matches the expected format. If a line does not match the format, it throws an exception with an error message indicating which line is invalid. It also checks if the substring from index 7 to 10 of the line is equal to "2000" and performs some action accordingly. You can integrate this code into your Selenium+Java automation framework to validate the file format.
Edit as per your concerns on the above:
You can modify the regular expression to match any variation of the expected format. For example, if the number of whitespace characters between each field can vary, you can use the \s character class in the regular expression to match any whitespace character, like this:
^[0-9]{7}[a-zA-Z\s]{7}[0-9]{3}\s+[0-9]{4}\s+[0-9]{5}\s+[a-zA-Z0-9\s]{7}[0-9]{7}$
This regular expression will match any line that has 7 digits, followed by 7 alphabetic or whitespace characters, followed by 3 digits, followed by one or more whitespace characters, followed by 4 digits, one or more whitespace characters, followed by 5 digits, one or more whitespace characters, followed by 7 alphanumeric or whitespace characters, followed by 7 digits.
To check only Line 2 for the substring (7,10) as 2000, you can simply check that substring only for Line 2, like this:
import java.io.File;
import java.io.IOException;
import java.nio.file.Files;
import java.util.List;
public class ValidateFileFormat {
public static void main(String[] args) {
File file = new File("path/to/file.txt");
try {
List<String> lines = Files.readAllLines(file.toPath());
for (int i = 0; i < lines.size(); i++) {
String line = lines.get(i);
if (i == 1) { // Check only Line 2
if (!line.substring(7, 10).equals("2000")) {
throw new Exception("Invalid substring in Line 2: " + line);
}
}
else {
if (!line.matches("^[0-9]{7}[a-zA-Z\\s]{7}[0-9]{3}\\s+[0-9]{4}\\s+[0-9]{5}\\s+[a-zA-Z0-9\\s]{7}[0-9]{7}$")) {
throw new Exception("Invalid file format in Line " + (i + 1) + ": " + line);
}
}
}
System.out.println("File format is valid.");
} catch (IOException e) {
e.printStackTrace();
} catch (Exception e) {
e.printStackTrace();
}
}
}
This code checks the substring (7,10) only for Line 2, and uses the modified regular expression to check the format of all other lines. If a line does not match the format, it throws an exception with an error message indicating which line is invalid.
Also note, if the format of every file is and each line in the file is going to be different, you will need to change your checking script and regular expression accordingly. It is also possible that you might also need to write more than one function to check different formats and file types.
