import java.io.File;
        import java.io.FileInputStream;
        import java.io.IOException;
        import java.io.InputStream;
        import java.text.DateFormat;
        import java.text.SimpleDateFormat;
        import org.apache.commons.net.ftp.FTP;
        import org.apache.commons.net.ftp.FTPClient;
        import org.apache.commons.net.ftp.FTPFile;
        import groovy.lang.*;
        import groovy.util.*;

        public class FTPUploadFileComparision {

            static String tmpDate = ""; //variable for store the last modified date

            public static void main(String[] args) {
                String server = "172.17.5.105"; //server ip
                int port = 21;                  //default port
                String user = "FTPUser";        //username
                String pass = "Santosh@123";  //password

                FTPClient ftpClient = new FTPClient();
                try {
                    ftpClient.connect(server, port);
                    ftpClient.login(user, pass);
                    ftpClient.enterLocalPassiveMode();
                    FTPFile[] files1 = ftpClient.listFiles("/");
                    DateFormat dateFormater = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
                    ftpClient.setFileType(FTP.BINARY_FILE_TYPE);
                    for (FTPFile file : files1) {
                        String details = file.getName();
                        if (file.isDirectory()) {
                            details = "[" + details + "]";
                        }
                        details += "tt" + file.getSize();
                        details += "tt" + dateFormater.format(file.getTimestamp().getTime());
                        compare(dateFormater.format(file.getTimestamp().getTime()), ftpClient);
                    }
                } catch (IOException ex) {
                    System.out.println("Error: " + ex.getMessage());
                    ex.printStackTrace();
                } finally {
                    try {
                        if (ftpClient.isConnected()) {
                            ftpClient.logout();
                            ftpClient.disconnect();
                        }
                    } catch (IOException ex) {
                        ex.printStackTrace();
                    }
                }
            }
        //method for compare the local file with ftp server file based on the last modified date

            public static void compare(String val, FTPClient ftpClient) throws IOException {
                String status = null;
                File f = new File("D:\Autoplus.txt");  //local file path
                Long modifiedTime1 = f.lastModified();
                DateFormat dateFormater = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");

                String str = dateFormater.format(modifiedTime1);
                if (str.compareTo(val) > 0) {      //local file last modified date is grater than ftp server file
                    //lastmodified date then delte the old file and place the new file//
                    tmpDate = val;
                    ftpClient.setFileType(FTP.BINARY_FILE_TYPE);

                    //  uploads first file using an InputStream stream into ftp server if local file last modified date is grater than ftp server file
                    // File firstLocalFile = new File(f);
                    InputStream inputStream = new FileInputStream(f);
                    String firstRemoteFile = "Autoplus.txt";
                    boolean done = ftpClient.storeFile(firstRemoteFile, inputStream);
                    inputStream.close();
                    if (done) {
                        System.out.println("The file is uploaded successfully.");
                    } else {
                        System.out.println("failed to upload the file");
                    }

                    //delete the file in ftp server if local file last modified date is grater then ftp server file
                    // Set a string with the file you want to delete
                    FTPFile[] files1 = ftpClient.listFiles("/FTP");
                    //ftpClient.setFileType(FTP.BINARY_FILE_TYPE);
                    for (FTPFile file : files1) {
                        String details = file.getName();

                        String filename = "FTP//" + details;

                        boolean exist = ftpClient.deleteFile(filename);

                        if (exist) {
                            System.out.println("File '" + filename + "' deleted...");
                        } // Notify user that file doesn't exist
                        else {
                            System.out.println("File '" + filename + "' doesn't exist...");
                        }
                    }

                } else if (str.compareTo(val) < 0) {
                    tmpDate = str;
                    System.out.println(tmpDate);

                } else {
                    status = "ok";
                    System.out.println("modified at same time");
                }

            }
        }