窗口上的文本行显示当前文件的路径，文本区用于编辑文件，3个按钮 [打开]，[保存…],[另存为…]。 单击[打开]按钮时，弹出打开文件对话框，将选择的文...

代码说明：

窗口上的文本行显示当前文件的路径，文本区用于编辑文件，3个按钮 [打开]，[保存…],[另存为…]。 单击[打开]按钮时，弹出打开文件对话框，将选择的文件显示在文本区中。 单击[保存…]按钮时，如果当前文件为空，则弹出保存文件对话框，并按设置的文件名保存文件；如果已有文件，则按设置的文件名保存文件。 单击[另存为…]按钮时，则弹出保存文件对话框，并按设置的文件名保存文件。 程序中以字符文件输出流FileWriter的writer方法写入文本区内容，以字符缓冲输入流BufferedReader的readLine()方法按行读取文本文件。 -window on the text line shows the path the current document, the text area for editing documents, three buttons [open] [preservation] [Save as ...]. Click [Open] button, pop open file dialog box, select the document in the text area. Click [preservation] button, if the current document is empty, save dialog pop up, together with a set of documents were preserved; If the document has been, according to the paper were set up to preserve documents. Click [Save as ...] button, the pop-up dialog box to preserve documents, together with a set of documents were preserved documents. Character procedures to document the output stream FileWriter way into the text writer District, characters in the input stream buffer