aplet.java

http://w3eval.calcsharp.net/ W3Eval is Java applet that evaluates mathematical expressions. It uses

package w3eval;

import java.awt.*;
import java.awt.event.*;
import java.applet.*;
import javax.swing.*;
import java.util.Vector;
import javax.swing.tree.DefaultMutableTreeNode;
import javax.swing.event.*;
import java.util.Enumeration;
import javax.swing.tree.TreePath;
import java.net.URL;
import java.net.MalformedURLException;

final public class Aplet extends JApplet
	{
   static public int drg='R';
   Vector varijable=new Vector();
   Vector operatori=new Vector();
   Vector funkcije=new Vector();
   DefaultMutableTreeNode user_defined=null;

	boolean isStandalone = false;
	JPanel jPanel1 = new JPanel();
   BorderLayout borderLayout1 = new BorderLayout();
   JSplitPane jSplitPane1 = new JSplitPane();
   JScrollPane jScrollPane1 = new JScrollPane();
   JTree drvo;
   JSplitPane jSplitPane2 = new JSplitPane();
   JScrollPane jScrollPane2 = new JScrollPane();
   JScrollPane jScrollPane3 = new JScrollPane();
   JTextArea izrazi = new JTextArea();
   JTextArea rezultat = new JTextArea();
   JPopupMenu izrazi_popup = new JPopupMenu();
   JMenuItem izrazi_explain_popup = new JMenuItem();
   JMenuItem izrazi_normalize_popup = new JMenuItem();
   JMenuItem izrazi_parse_popup = new JMenuItem();
   // JMenuItem izrazi_help_popup = new JMenuItem();
   JMenuItem izrazi_about_popup = new JMenuItem();
   JMenuItem izrazi_evaluate_popup = new JMenuItem();
   JMenuItem izrazi_reduce_popup = new JMenuItem();
   JMenuItem izrazi_foreground_popup = new JMenuItem();
   JMenuItem izrazi_background_popup = new JMenuItem();
   JPopupMenu rezultat_popup = new JPopupMenu();
   JMenuItem rezultat_background_popup = new JMenuItem();
   JMenuItem rezultat_foreground_popup = new JMenuItem();
   JPopupMenu drvo_popup = new JPopupMenu();
   JMenuItem drvo_expand_popup = new JMenuItem();
   JMenuItem drvo_collapse_popup = new JMenuItem();
   JMenuItem izrazi_select_popup = new JMenuItem();
   JMenuItem izrazi_variables_popup = new JMenuItem();
   JRadioButtonMenuItem jRadioButtonMenuItem1 = new JRadioButtonMenuItem();
   JRadioButtonMenuItem jRadioButtonMenuItem2 = new JRadioButtonMenuItem();
   JRadioButtonMenuItem jRadioButtonMenuItem3 = new JRadioButtonMenuItem();
   ButtonGroup buttonGroup1 = new ButtonGroup();
   JMenuItem drvo_expand_selection_popup = new JMenuItem();
   JMenuItem drvo_collapse_selection_popup = new JMenuItem();
   JMenuItem izrazi_clear_popup = new JMenuItem();
   JMenu jMenu1 = new JMenu();
   JMenuItem jMenuItem1 = new JMenuItem();
   JMenuItem jMenuItem2 = new JMenuItem();
   JMenuItem jMenuItem3 = new JMenuItem();

	public String getParameter(String key, String def)
    {
    return isStandalone ? System.getProperty(key, def) :
      (getParameter(key) != null ? getParameter(key) : def);
    }

  public Aplet()
    {
    }

  public void init()
    {
    try
      {
      jbInit();
      }
    catch(Exception e)
      {
      e.printStackTrace();
      }
    }

  // inicijalizacija komponenti
  private void jbInit() throws Exception
    {

      DefaultMutableTreeNode korijen = new DefaultMutableTreeNode( "W3Eval" );
      popunjavanje_drva( korijen );
      drvo=new JTree( korijen );

      drvo.expandRow( 3 );
      drvo.expandRow( 2 );
      drvo.expandRow( 1 );

      this.setSize(new Dimension(760, 400));
      jPanel1.setBorder(BorderFactory.createLineBorder(Color.black));
      jPanel1.setLayout(borderLayout1);
      jSplitPane2.setOrientation(JSplitPane.VERTICAL_SPLIT);
      jSplitPane2.setBorder(null);
      izrazi.setText("Hint : Right-click here!");
      // rezultat.setText("W3Eval DEMO");
      izrazi.addKeyListener(new java.awt.event.KeyAdapter()
      {

         public void keyPressed(KeyEvent e)
         {
            izrazi_keyPressed(e);
         }
      });
      // rezultat.setText("jTextArea2");
      jScrollPane3.setBorder(null);
      jScrollPane2.setBorder(null);
      jScrollPane1.setBorder(null);
      jSplitPane1.setBorder(null);
      rezultat.addKeyListener(new java.awt.event.KeyAdapter()
      {

         public void keyPressed(KeyEvent e)
         {
            rezultat_keyPressed(e);
         }
      });
      drvo.addMouseListener(new java.awt.event.MouseAdapter()
      {

         public void mouseClicked(MouseEvent e)
         {
            drvo_mouseClicked(e);
         }
      });
      drvo.addKeyListener(new java.awt.event.KeyAdapter()
      {

         public void keyPressed(KeyEvent e)
         {
            drvo_keyPressed(e);
         }
      });
      // izrazi_explain_popup.setMnemonic('1');
      izrazi_explain_popup.setText("Explain");
      izrazi_explain_popup.addActionListener(new java.awt.event.ActionListener()
      {

         public void actionPerformed(ActionEvent e)
         {
            izrazi_explain_popup_actionPerformed(e);
         }
      });
      izrazi_normalize_popup.setText("Normalize");
      izrazi_normalize_popup.addActionListener(new java.awt.event.ActionListener()
      {

         public void actionPerformed(ActionEvent e)
         {
            izrazi_normalize_popup_actionPerformed(e);
         }
      });
      izrazi_parse_popup.setText("Parse");
      izrazi_parse_popup.addActionListener(new java.awt.event.ActionListener()
      {

         public void actionPerformed(ActionEvent e)
         {
            izrazi_parse_popup_actionPerformed(e);
         }
      });

      /*
      izrazi_help_popup.setText("Help");
      izrazi_help_popup.addActionListener(new java.awt.event.ActionListener()
      {

         public void actionPerformed(ActionEvent e)
         {
            izrazi_help_popup_actionPerformed(e);
         }
      });
      */

      // izrazi_about_popup.setMnemonic(' ');
      izrazi_about_popup.setText("About");
      izrazi_about_popup.addActionListener(new java.awt.event.ActionListener()
      {

         public void actionPerformed(ActionEvent e)
         {
            izrazi_about_popup_actionPerformed(e);
         }
      });
      izrazi_evaluate_popup.setText("Evaluate");
      izrazi_evaluate_popup.addActionListener(new java.awt.event.ActionListener()
      {

         public void actionPerformed(ActionEvent e)
         {
            izrazi_evaluate_popup_actionPerformed(e);
         }
      });
      izrazi_reduce_popup.setText("Reduce");
      izrazi_reduce_popup.addActionListener(new java.awt.event.ActionListener()
      {

         public void actionPerformed(ActionEvent e)
         {
            izrazi_reduce_popup_actionPerformed(e);
         }
      });
      izrazi.addMouseListener(new java.awt.event.MouseAdapter()
      {

         public void mouseClicked(MouseEvent e)
         {
            izrazi_mouseClicked(e);
         }
      });
      izrazi_background_popup.setText("Change background color ");
      izrazi_background_popup.addActionListener(new java.awt.event.ActionListener()
      {

         public void actionPerformed(ActionEvent e)
         {
            izrazi_background_popup_actionPerformed(e);
         }
      });
      izrazi_foreground_popup.setText("Change foreground color");
      izrazi_foreground_popup.addActionListener(new java.awt.event.ActionListener()
      {

         public void actionPerformed(ActionEvent e)
         {
            izrazi_foreground_popup_actionPerformed(e);
         }
      });
      rezultat_background_popup.setText("Change background color");
      rezultat_background_popup.addActionListener(new java.awt.event.ActionListener()
      {

         public void actionPerformed(ActionEvent e)
         {
            rezultat_background_popup_actionPerformed(e);
         }
      });
      rezultat_foreground_popup.setText("Change foreground color");
      rezultat_foreground_popup.addActionListener(new java.awt.event.ActionListener()
      {

         public void actionPerformed(ActionEvent e)
         {
            rezultat_foreground_popup_actionPerformed(e);
         }
      });
      rezultat.addMouseListener(new java.awt.event.MouseAdapter()
      {

         public void mouseClicked(MouseEvent e)
         {
            rezultat_mouseClicked(e);
         }
      });
      drvo_expand_popup.setText("Expand all");
      drvo_expand_popup.addActionListener(new java.awt.event.ActionListener()
      {

         public void actionPerformed(ActionEvent e)
         {
            drvo_expand_popup_actionPerformed(e);
         }
      });
      drvo_collapse_popup.setText("Collapse all");
      drvo_collapse_popup.addActionListener(new java.awt.event.ActionListener()
      {

         public void actionPerformed(ActionEvent e)
         {
            drvo_collapse_popup_actionPerformed(e);
         }
      });
      izrazi_select_popup.setText("Select");
      izrazi_select_popup.addActionListener(new java.awt.event.ActionListener()
      {

         public void actionPerformed(ActionEvent e)
         {
            izrazi_select_popup_actionPerformed(e);
         }
      });
      izrazi_variables_popup.setText("Variables");
      izrazi_variables_popup.addActionListener(new java.awt.event.ActionListener()
      {

         public void actionPerformed(ActionEvent e)
         {
            izrazi_variables_popup_actionPerformed(e);
         }
      });
      jRadioButtonMenuItem1.setText("Deg");
      jRadioButtonMenuItem2.setSelected(true);
      jRadioButtonMenuItem2.setText("Rad");
      jRadioButtonMenuItem3.setText("Grad");
      drvo_expand_selection_popup.setText("Expand selection");
      drvo_expand_selection_popup.addActionListener(new java.awt.event.ActionListener()
      {

         public void actionPerformed(ActionEvent e)
         {
            drvo_expand_selection_popup_actionPerformed(e);
         }
      });
      drvo_collapse_selection_popup.setText("Collapse selection");
      drvo_collapse_selection_popup.addActionListener(new java.awt.event.ActionListener()
      {

         public void actionPerformed(ActionEvent e)
         {
            drvo_collapse_selection_popup_actionPerformed(e);
         }
      });
      izrazi_clear_popup.setText("Clear");
      izrazi_clear_popup.addActionListener(new java.awt.event.ActionListener()
      {

         public void actionPerformed(ActionEvent e)
         {
            izrazi_clear_popup_actionPerformed(e);
         }
      });
      jMenu1.setText("Change Look&Feel");

      jMenuItem1.setText("Java");
      jMenuItem1.addActionListener(new java.awt.event.ActionListener()
      {

         public void actionPerformed(ActionEvent e)
         {
            jMenuItem1_actionPerformed(e);
         }
      });
      jMenuItem2.setText("Windows");