编写一个应用程序，可以打开、读取、显示一个可读文件的内容。提示：利用文本编辑器将事先编写好的程序输入计算机中，按Java Applet小应用程序的编译和运行方法进行操作，查看显示结果。-Write an application that can open, read, display a readable document. Tip: Use a text editor program will be well prepared in advance input into the computer, press a small Java Applet to compile and run the application methods of operation, view displays the results.