Java编写实现一个FTP客户端程序，通过该客户端连接指定的服务器。useFtpApplet 类继承了Applet 类，在init()中实现的是此Applet 的初始化，设置布局和背景，建立文本、标签和文本域。

　　Connect()方法使用主机地址、用户名和密码作为参数，建立与主机的连接。使用new 生成新的FtpClient 类实例，使用login()方法登录FTP 服务器，调用showFileContents()方法显示文件内容。 -Java prepared to achieve an FTP client program, through which clients connect to the specified server. useFtpApplet class inherits the Applet class, init () is initialized in the realization of this Applet, set the layout and background, the establishment of the text, labels and text fields.

Connect () method uses the host address, user name and password as parameters to establish a connection with the host. Use new FtpClient generate a new instance of the class, using the login () method to log FTP server, call showFileContents () method to display the file contents.