Java

Read Text at a String Offset from a Remote SFTP File

Demonstrates the Chilkat SFtp.ReadFileText64s method, which is like ReadFileText64 but takes the byte offset as a decimal string. The arguments are the handle, the offset string, the maximum number of bytes, and the charset.

Background: The string-offset read exists for the same reason as its write counterpart: it lets code in languages without convenient 64-bit integers still address positions in very large files by supplying the offset as text. Functionally it is identical to the int64 version.

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import com.chilkatsoft.chilkat2.ChilkatException;
import com.chilkatsoft.chilkat2.SFtp;

public class ChilkatExample {

    public static void main(String[] args) {
        // Demonstrates the SFtp.ReadFileText64s method, which is like ReadFileText64 but takes the byte
        // offset as a decimal string.  The 1st argument is the handle, the 2nd is the offset string, the
        // 3rd is the maximum number of bytes, and the 4th is the charset.

        SFtp sftp = new SFtp();

        // Connect, authenticate, and initialize the SFTP subsystem.
        int port = 22;
        try {
            sftp.connect("sftp.example.com", port);
        } catch (ChilkatException e) {
            System.out.println(e.getLastErrorText());
            return;
        }

        // Normally you would not hard-code the password in source.  You should instead obtain it
        // from an interactive prompt, environment variable, or a secrets vault.
        String password = "mySshPassword";

        String handle;
        try {
            sftp.authenticatePw("mySshLogin", password);

            sftp.initializeSftp();

            handle = sftp.openFile("subdir/hugefile.dat", "readOnly", "openExisting");
        } catch (ChilkatException e) {
            System.out.println(e.getLastErrorText());
            return;
        }

        // Supplying the offset as a string is convenient in languages without a native 64-bit integer.
        String offset = "5000000000";
        int numBytes = 6;
        String text;
        try {
            text = sftp.readFileText64s(handle, offset, numBytes, "utf-8");
        } catch (ChilkatException e) {
            System.out.println(e.getLastErrorText());
            return;
        }

        System.out.println(text);

        try {
            sftp.closeHandle(handle);
        } catch (ChilkatException e) {
            System.out.println(e.getLastErrorText());
            return;
        }

        sftp.disconnect();
    }
}