JDK1.7以上javaFTP上传删除文件

package com.itv.launcher.util;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.net.InetSocketAddress;
import java.util.Properties;
import java.util.StringTokenizer;

import sun.net.TelnetOutputStream;
import sun.net.ftp.FtpClient;
import sun.net.ftp.FtpProtocolException;

/**
 * FTP上传工具类
 *
 * @author yanzhou
 * @version v1.0
 */
public class FTPUtil {

    private static FtpClient ftpClient = null ;
    private static final String url;
    private static final int port;
    private static final String user;
    private static final String password;
    private static final String remoteFilePath;

    static {
        Properties FTPPro = ReadFTPProperties.getMsgFromPro();
        url = FTPPro.getProperty( "FTP_URL" );
        port = Integer.parseInt(FTPPro.getProperty( "FTP_PORT" ));
        user = FTPPro.getProperty( "FTP_USER" );
        password = FTPPro.getProperty( "FTP_PASSWORD" );
        remoteFilePath = FTPPro.getProperty( "FTP_REMOTE_FILEPATH" );

    }

    /**
     * 链接FTP
     * @throws FtpProtocolException
     */
    private static void connectFTP() throws FtpProtocolException {
        try {
            ftpClient = FtpClient.create();
            ftpClient.connect( new InetSocketAddress(url, port));
            ftpClient.login(user, password.toCharArray());
            ftpClient.setBinaryType();
            if (! "" .equals(remoteFilePath) && remoteFilePath != null ) {
                ftpClient.changeDirectory(remoteFilePath);
            }
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    /**
     * 关闭FTP链接
     */
    public static void closeFTP() {
        try {
            if (ftpClient != null ) {
                ftpClient.close();
            }
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    /**
     * 上传文件到FTP
     * @param file file文件，struts2从页面得到的File类型
     * @param filePath 要保存在FTP上的路径（文件夹）
     * @param fileName 文件名（test001.jpg）
     * @return 文件是否上传成功
     * @throws Exception
     */
    public static boolean upload(File file, String filePath, String fileName) {
        TelnetOutputStream to = null ;
        FileInputStream fi = null ;
        filePath = remoteFilePath + Constants.FILE_SEPARATOR + filePath;
        try {
            if (file != null ) {
                connectFTP();
                if (!isDirExist(filePath.replace( "\\" , "/" ))) {
                    createDir(filePath.replace( "\\" , "/" ));
                    ftpClient.changeDirectory(filePath.replace( "\\" , "/" ));
                }
                fi = new FileInputStream(file);
                to = (TelnetOutputStream) ftpClient.putFileStream(fileName, true );
                byte [] bytes = new byte [ 1024 ];
                int i = fi.read(bytes);
                while (i != - 1 ) {
                    to.write(bytes);
                    i = fi.read(bytes);
                }
            }
            return true ;
        } catch (FileNotFoundException e1) {
            return false ;
        } catch (IOException e2) {
            return false ;
        } catch (Exception e) {
            return false ;
        } finally {
            if (fi != null ) {
                try {
                    fi.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
            if (to != null ) {
                try {
                    to.flush();
                    to.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
            closeFTP();
        }
    }

    /**
     * 删除FTP制定目录下的文件
     * @param filePath 文件在FTP存储的路径
     * @param fileName 要删除的文件名称
     * @return 是否删除成功
     */
    public static boolean deleteFileFtp(String filePath, String fileName){
        try {
            connectFTP();
            filePath = remoteFilePath + Constants.FILE_SEPARATOR + filePath + Constants.FILE_SEPARATOR;
            if (!isDirExist(filePath.replace( "\\" , "/" ))) {
                return false ;
            }
            ftpClient.changeDirectory(filePath.replace( "\\" , "/" ));
            ftpClient.deleteFile(fileName);
            return true ;
        } catch (Exception e) {
            e.printStackTrace();
            return false ;
        } finally {
            closeFTP();
        }
    }
    /**
     * 检查文件夹是否存在
     *
     * @param dir
     * @param ftpClient
     * @return
     */
    private static Boolean isDirExist(String dir) {
        try {
            ftpClient.changeDirectory(dir);
        } catch (Exception e) {
            return false ;
        }
        return true ;
    }

    /**
     * 创建文件夹
     *
     * @param dir
     * @param ftpClient
     * @throws Exception
     */
    private static void createDir(String dir) throws Exception {
        ftpClient.setAsciiType();
        StringTokenizer s = new StringTokenizer(dir, "/" ); // sign
        s.countTokens();
        String pathName = "" ;
        while (s.hasMoreElements()) {
            pathName = pathName + "/" + (String) s.nextElement();
            try {
                ftpClient.makeDirectory(pathName);
            } catch (Exception e) {
                e = null ;
            }
        }
        ftpClient.setBinaryType();

    }

}

2. [代码]常量类，系统的路径分隔符     

package com.itv.launcher.util;

public interface Constants {

    //路径分隔符
    public static String FILE_SEPARATOR = System.getProperty( "file.separator" );
}

3. [代码]FTP链接的配置properties文件，包括用户名密码一些信息     

#FTP的IP地址
FTP_URL= 127.0 . 0.1
#FTP端口号
FTP_PORT= 1234
#用户名
FTP_USER=yanzhou
#密码
FTP_PASSWORD=abcdefg12345
#FTP账号目录
FTP_REMOTE_FILEPATH=