import?java.awt.*;
import?java.awt.event.*;
import?java.io.BufferedReader;
import?java.io.FileReader;
import?java.util.*;

import?javax.swing.*;


public?class?tuidao?implements?ActionListener?{
	String?[]s1;???//存放產(chǎn)生式的字符串?dāng)?shù)組
	String?s2s3s4sb1;?????//s2存放要分析的字符串
	StringBuffer?sb;
	Jframe?f;
	JLabel?L1L2;
	JButton?b1b2b3b4;
	JTextField?tf;
	JTextArea?tata1ta2;
	JScrollPane??spsp1sp2;
	JPanel?p1p2p3p4;
	JFileChooser?fc1fc2;
	public?void?actionPerformed（ActionEvent?e）?{
		//?TODO?Auto-generated?method?stub
?????????if（e.getSource（）==b1）
?????????{
????????	?//tf.setEditable（true）;
????????	?//ta.setEditable（true）;
????????	?String?ss=““;
????????	?fc1=new?JFileChooser（）;
????????	?if（fc1.showOpenDialog（f）==0）
????????	?{
????????		?try
????????		?