ll_1_frame.java

编译原理的实验

import java.awt.Dimension;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
import java.util.Stack;

import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JScrollPane;
import javax.swing.JTextArea;
import javax.swing.JTextField;
import javax.swing.border.TitledBorder;

public class LL_1_Frame extends JFrame {
	final JTextField textField;
	final JTextArea textArea_2;
	final JTextArea textArea_1;
	final JTextArea textArea;
	final JButton goButton = new JButton();
	Stack<Character> mystack = new Stack<Character>();
	String[][] analysistable = new String[5][6];

	Nonterminal E = new Nonterminal('E', 0);
	Nonterminal D = new Nonterminal('D', 1);// replace E'
	Nonterminal T = new Nonterminal('T', 2);
	Nonterminal R = new Nonterminal('R', 3);// replace T'
	Nonterminal F = new Nonterminal('F', 4);
	private char[] inputsymbol = new char[6];
	String output;
	String input;
	public LL_1_Frame() {
		super("LL(1)文法分析模拟");
		analysistable[0][0] = "TD";
		analysistable[0][3] = "TD";
		analysistable[1][1] = "+TD";
		analysistable[1][4] = "";
		analysistable[1][5] = "";
		analysistable[2][0] = "FR";
		analysistable[2][3] = "FR";
		analysistable[3][1] = "";
		analysistable[3][2] = "*FR";
		analysistable[3][4] = "";
		analysistable[3][5] = "";// replace:reduce to ∈
		analysistable[4][0] = "i";
		analysistable[4][3] = "(E)";
		output = "";
		inputsymbol[0] = 'i';
		inputsymbol[1] = '+';
		inputsymbol[2] = '*';
		inputsymbol[3] = '(';
		inputsymbol[4] = ')';
		inputsymbol[5] = '$';
		mystack.push('$');
		mystack.push(E.symbol);
		// /////////////////////////////////////////////////////
		this.setVisible(true);
		getContentPane().setLayout(null);

		final JScrollPane scrollPane = new JScrollPane();
		scrollPane.setBounds(43, 99, 132, 193);
		getContentPane().add(scrollPane);

		textArea = new JTextArea();
		textArea.setEditable(false);
		textArea.setBorder(new TitledBorder(null, "栈", TitledBorder.CENTER,
				TitledBorder.DEFAULT_POSITION, null, null));
		scrollPane.setViewportView(textArea);

		final JScrollPane scrollPane_1 = new JScrollPane();
		scrollPane_1.setBounds(192, 99, 100, 193);
		getContentPane().add(scrollPane_1);

		textArea_1 = new JTextArea();
		textArea_1.setEditable(false);
		textArea_1.setBorder(new TitledBorder(null, "输入", TitledBorder.CENTER,
				TitledBorder.DEFAULT_POSITION, null, null));
		scrollPane_1.setViewportView(textArea_1);

		final JScrollPane scrollPane_2 = new JScrollPane();
		scrollPane_2.setBounds(307, 99, 109, 193);
		getContentPane().add(scrollPane_2);

		textArea_2 = new JTextArea();
		textArea_2.setEditable(false);
		textArea_2.setBorder(new TitledBorder(null, "输出", TitledBorder.CENTER,
				TitledBorder.DEFAULT_POSITION, null, null));
		scrollPane_2.setViewportView(textArea_2);

		final JLabel label = new JLabel();
		label.setText("请输入表达式( e.g.  i+i*i$):");
		label.setBounds(43, 21, 152, 25);
		getContentPane().add(label);

		textField = new JTextField();
		textField.setBounds(201, 22, 120, 22);
		getContentPane().add(textField);

		goButton.addActionListener(new Running());
		goButton.setText("Run");
		goButton.setBounds(357, 19, 82, 28);
		getContentPane().add(goButton);
		this.addWindowListener(new WindowAdapter() {
			public void windowClosed(WindowEvent e) {
				dispose();
				System.exit(0);
			}
		});
		this.setLocation(300, 200);
		this.setPreferredSize(new Dimension(500, 400));
		this.pack();
		this.setResizable(false);
	}

	class Running implements ActionListener {
		public void actionPerformed(ActionEvent e) {
			textField.setEditable(false);
			new Exec().start();
			goButton.setEnabled(false);
		}

	}

	class Exec extends Thread {
		public void run() {
			input = textField.getText();
			for (int i = 0; i < input.length(); i++) {
				/*System.out.println(mystack.toString() + "\t"
						+ input.substring(i) + "\t" + output);*/
				textArea.append(mystack.toString()+"\n");
				textArea_1.append(input.substring(i)+"\n");
				textArea_2.append(output+"\n");
				output = "";
				if (mystack.peek() != input.charAt(i)) {
					char temp = mystack.pop();
					char temp2 = input.charAt(i);
					String str = analysistable[LL_1.getseq(temp)][LL_1
							.getinputseq(temp2)];
					for (int j = str.length() - 1; j >= 0; j--) {
						mystack.push(str.charAt(j));
					}
					output = temp + "->" + str;
					i = i - 1;

				} else {
					mystack.pop();
				}
				try {
					sleep(1000);
				} catch (InterruptedException e) {
					e.printStackTrace();
				}
			}
		}
	}

	public static void main(String[] args) {
		new LL_1_Frame();
	}

	public static int getseq(char ch) {//得到非终结符在分析表中的对应的行数
		int temp = -1;
		switch (ch) {
		case 'E':
			temp = 0;
			break;
		case 'D':
			temp = 1;
			break;
		case 'T':
			temp = 2;
			break;
		case 'R':
			temp = 3;
			break;
		case 'F':
			temp = 4;
			break;
		}
		return temp;
	}

	public static int getinputseq(char ch) {//得到输入符号在分析表中的对应列数
		int temp = -1;
		switch (ch) {
		case 'i':
			temp = 0;
			break;
		case '+':
			temp = 1;
			break;
		case '*':
			temp = 2;
			break;
		case '(':
			temp = 3;
			break;
		case ')':
			temp = 4;
			break;
		case '$':
			temp = 5;
			break;
		}
		return temp;
	}
}