JAVA FTP 连接 及判断文件是否存在

JAVA FTP 连接 及判断文件是否存在
package com.gy.util;import org.apache.commons.net.ftp.FTPClient;import org.apache.commons.net.ftp.FTPFile;import org.apache.commons.net.ftp.FTPReply;import org.junit.Test;public class FtpUtil1111 {    private static  String url = "192.168.1.1";    private static  int port = 21;    private static  String username = "xxxxx";    private static  String password = "xxxxx";    @Test    public void test(){        for(int i=0;i<1;i++){            boolean rs =  isExsits("/test/20170822/1300004/20170822-184800-184859-01-P-0-1.264.flv");            System.out.println("rs==="+i+"  :"+rs);        }    }    /***     * 判断文件是否存在     * @param ftpPath     * @return     */    public static boolean isExsits(String ftpPath){        FTPClient ftpx = getFTPClient( url,  port,  username,  password);        try {            FTPFile[] files =ftpx.listFiles(ftpPath);            if(files!=null&&files.length>0){                System.out.println("files size:"+files[0].getSize());                return true;            }else {                return false;            }        } catch (Exception e) {            //重新连接一次，可以么？            try {                Thread.sleep(1000);            } catch (Exception e1) {            }            System.out.println("重新连接....");            ftp = null;            return isExsits(ftpPath);            //e.printStackTrace();        }    }    private static FTPClient ftp;    public  static FTPClient getFTPClient(String url, int port, String username, String password){        if(ftp!=null)return ftp;        FTPClient ftptemp = new FTPClient();        try {            int reply;            ftptemp.connect(url, port);            ftptemp.login(username, password);            reply = ftptemp.getReplyCode();            if (!FTPReply.isPositiveCompletion(reply)) {                ftptemp.disconnect();            }            ftp = ftptemp;        } catch (Exception e) {            System.out.println(e.getMessage());        }        return ftp;    } }