Have you had experience working with integrations based on file transfer methods?

Yes, file-based data transfer methods are often used for exchanging information between systems that do not have direct network interaction or when asynchronous data transfer is required.

A typical example is exporting data to a CSV or XML file, which is then transferred via FTP or through a shared network drive, after which another system reads and processes this file.

In Java, this might look like:

// Writing data to a CSV file
try (BufferedWriter writer = new BufferedWriter(new FileWriter("data.csv"))) {
    writer.write("id,name,age\n");
    writer.write("1,Ivan,30\n");
    writer.write("2,Maria,25\n");
}

The file is then transferred or read by another system. This approach is simple but requires control over file integrity and error handling during transfer.