notepadframe.java

递归子程序法：对应每个非终结符语法单元编一个独立的处理过程（或子程序）。语法分析从读入第一个单词开始

	package notepadshow;
	/** 
	 * Java语言实验参考程序
	 * Company 北京师范大学计算机系
 
	 * @author 孙一林
	 * @version 1.0
	 */
	import java.awt.*;
	import java.awt.event.*;
	import javax.swing.*;
	import java.io.*;
	public class NotepadFrame extends JFrame {
	  JPanel contentPane;
	  JToolBar jToolBar = new JToolBar();
	  JButton jButton1 = new JButton();
	  JButton jButton2 = new JButton();
	  ImageIcon image1;
	  ImageIcon image2;
	  JTextArea jTextArea1 = new JTextArea();
	  JFileChooser jFileChooser1 = new JFileChooser();
	  public NotepadFrame() {
	    enableEvents(AWTEvent.WINDOW_EVENT_MASK);
	    try {
	      jInit();
	    }
	    catch(Exception e) {
	      e.printStackTrace();
	    }
	  }
	  private void jInit() throws Exception  {
	    image1 = new ImageIcon(
			notepadshow.NotepadFrame.class.getResource("openFile.gif"));
	    image2 = new ImageIcon(
			notepadshow.NotepadFrame.class.getResource("saveFile.gif"));
		contentPane = (JPanel) this.getContentPane();
	    contentPane.setLayout(null);
	    this.setSize(new Dimension(400, 300));
	    this.setTitle("记事本");
	    jButton1.setToolTipText("Open File");
	    jButton2.setIcon(image2);
	    jButton2.setToolTipText("Save File");
	    jTextArea1.setBounds(new Rectangle(0, 30, 400, 270));
	    jToolBar.setBounds(new Rectangle(0, 0, 400, 30));
	    jFileChooser1.setSelectedFiles(null);
	    jFileChooser1.setDialogTitle("");
	    jFileChooser1.setAutoscrolls(true);
	    jFileChooser1.setToolTipText("");
	    jFileChooser1.setBounds(new Rectangle(360, 30, 10, 10));
	    jToolBar.add(jButton1);
	    jToolBar.add(jButton2);
	    contentPane.add(jFileChooser1, null);
	    contentPane.add(jTextArea1, null);
	    contentPane.add(jToolBar, null);
	    jButton1.setIcon(image1);
	    jButton1.addActionListener(new java.awt.event.ActionListener() {
	      public void actionPerformed(ActionEvent e) {
	        jButton1_actionPerformed(e);
	      }
	    });
	    jButton2.addActionListener(new java.awt.event.ActionListener() {
	      public void actionPerformed(ActionEvent e) {
	        jButton2_actionPerformed(e);
	      }
	    });
	  }
	  protected void processWindowEvent(WindowEvent e) {
	    super.processWindowEvent(e);
	    if (e.getID() == WindowEvent.WINDOW_CLOSING) {
	      System.exit(0);
	    }
	  }
	  void jButton1_actionPerformed(ActionEvent e) {
	    int val = jFileChooser1.showOpenDialog(this);
	    String myFileName = jFileChooser1.getSelectedFile().getName();
	    try{
	      FileInputStream myfile = new FileInputStream(myFileName);
	      byte buff[] = new byte[myfile.available()];
	      val = myfile.read(buff);
	      myfile.close();
	      String s = new String(buff);
	      jTextArea1.setText(s);
	    }
	    catch(IOException ioe){
	    }
	  }
	  void jButton2_actionPerformed(ActionEvent e) {
	    int val = jFileChooser1.showSaveDialog(this);
	    String myFileName = jFileChooser1.getSelectedFile().getName();
	    try{
	      File file = new File (myFileName);
	      FileWriter outText = new FileWriter(file);
	      String text = jTextArea1.getText();
	      outText.write(text);
	      outText.close();
	    }
	    catch(IOException ioe){
	    }
	  }
	}