Calculation in the cell ( Spreadsheet application ) =3+2

Hi,

I am writing a spreadsheet application, If I will type "=3+2"(without quotes) in the cell and press enter, I want it to calculate it and show 5 in the cell. Is that possible?

Here is my code:

import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
import javax.swing.table.*;
import java.util.*;
import javax.swing.event.*;

class  tableExample implements ActionListener, TableModelListener
{
JFrame frame;
JTable table;
Vector rows,columns;
DefaultTableModel tabModel;
JScrollPane scrollPane;
JLabel lblMessage;
JButton cmdOpen,cmdSave,cmdNew,cmdAdd,cmdDelete,cmdSetValue,cmdGetValue;
JPanel mainPanel,buttonPanel;


   public static void main(String[] args)
    {
tableExample t=new tableExample();
    }

tableExample()
{
rows=new Vector();
columns= new Vector();
String[] columnNames =
{
"A",
"B",
"C",
"D",
"E",
"F",
"G"
};
addColumns(columnNames);

tabModel=new DefaultTableModel();
tabModel.setDataVector(rows,columns);

table = new JTable(tabModel);
scrollPane= new JScrollPane(table);//ScrollPane

table.setRowSelectionAllowed(false);

table.getModel().addTableModelListener(this);

lblMessage=new JLabel("");


buttonPanel=new JPanel();
cmdOpen=new JButton("Open File");
cmdSave=new JButton("Save File");
cmdNew=new JButton("New File");
cmdAdd=new JButton("Add Row");
cmdDelete=new JButton("Delete") ;
cmdSetValue=new JButton("Set Value");
cmdGetValue=new JButton("Get Value");

buttonPanel.add(cmdOpen);
buttonPanel.add(cmdSave);
buttonPanel.add(cmdNew);
buttonPanel.add(cmdAdd);
buttonPanel.add(cmdDelete);
buttonPanel.add(cmdSetValue);
buttonPanel.add(cmdGetValue);

cmdOpen.addActionListener(this);
cmdSave.addActionListener(this);
cmdNew.addActionListener(this);
cmdAdd.addActionListener(this);
cmdDelete.addActionListener(this);
cmdSetValue.addActionListener(this);
cmdGetValue.addActionListener(this);

mainPanel=new JPanel();
frame=new JFrame("Table Example");
frame.setSize(800,600);
frame.setExtendedState(JFrame.MAXIMIZED_BOTH);
mainPanel.setLayout(new BorderLayout());
mainPanel.add("Center",scrollPane);
mainPanel.add("South",buttonPanel);
mainPanel.setBackground(Color.white);
buttonPanel.setBackground(Color.white);
table.getParent().setBackground(Color.black);
frame.getContentPane().add(mainPanel);
frame.setVisible(true);
mainPanel.setBorder(BorderFactory.createLineBorder(Color.black));

}
 public void addColumns(String[] colName)//Table Columns
{
for(int i=0;i<colName.length;i++)
columns.addElement((String) colName[i]);
}

public void addRow() //Add Row
{
Vector r=new Vector();
r=createBlankElement();
rows.addElement(r);
table.addNotify();

}

// Start of Open File Class
public void openFile() //Open File
{
     JFileChooser fc = new JFileChooser();
     int returnVal = fc.showOpenDialog(cmdOpen);
}

public void saveFile() //Save File
{
     JFileChooser fc = new JFileChooser();
     int returnVal = fc.showSaveDialog(cmdSave);    
}

public void newFile() //New File
{
     JFileChooser fc = new JFileChooser();
     int returnVal = fc.showOpenDialog(cmdNew);    
}

 public Vector createBlankElement()
{
Vector t = new Vector();
t.addElement((String) " ");
t.addElement((String) " ");
t.addElement((String) " ");
t.addElement((String) " ");
t.addElement((String) " ");
t.addElement((String) " ");
t.addElement((String) " ");
return t;
}

 void deleteRow(int index)
   {
     if(index!=-1)//At least one Row in Table
      {
        rows.removeElementAt(index);
        table.addNotify();
       }

   }//Delete Row

 public void tableChanged(javax.swing.event.TableModelEvent source)     {
                 String msg="";
                 TableModel tabMod = (TableModel)source.getSource();
          switch (source.getType())
                   {
                       case TableModelEvent.UPDATE:
                       msg="Table Value Updated for  cell "+table.getSelectedRow()+","+table.getSelectedColumn()+"\nWhich is "+table.getValueAt(table.getSelectedRow(),table.getSelectedColumn()).toString();
              JOptionPane.showMessageDialog(null,msg,"Table Example",JOptionPane.INFORMATION_MESSAGE);
                break;

                   }

    }//Table Changed Method

public void selectCell(int row,int col)
    {
         if(row!=-1 && col !=-1)            
          {
          table.setRowSelectionInterval(row,row);
          table.setColumnSelectionInterval(col,col);
          }
    }


public void actionPerformed(ActionEvent source)
    {
          if (source.getSource()==(JButton) cmdOpen)
          {
               openFile();
          }
          if (source.getSource()==(JButton) cmdSave)
          {
               saveFile();
          }
          if (source.getSource()==(JButton) cmdNew)
          {
               newFile();
          }
         if (source.getSource()==(JButton) cmdAdd)
         {
             addRow();
         }
         if (source.getSource()==(JButton) cmdDelete)
         {
             deleteRow(table.getSelectedRow());
         }
         if (source.getSource()==(JButton) cmdSetValue)
         {
          String CName=JOptionPane.showInputDialog(null,"Enter Value to be set at Cell 0,2 ","Simple Table Example",JOptionPane.INFORMATION_MESSAGE);
              if(!CName.trim().equals("") && table.getRowCount()>0)
              {
                  selectCell(0,2);
                  table.setValueAt(CName,0,2);
              }
         }
         if (source.getSource()==(JButton) cmdGetValue)
         {
            if(table.getRowCount()>0)
             {
           String msg="Value At cell 0,0 is "+table.getValueAt(0,0).toString();
           JOptionPane.showMessageDialog(null,msg,"Table Example",JOptionPane.INFORMATION_MESSAGE);
             }
     }
   
    }//ActionList

}
johnmarcoAsked:
Who is Participating?
 
rama_krishna580Commented:
0
 
hoomanvCommented:
evaluating a math expression is somewhat not easy
you have to first convert it to Postfix and then evaluating the Postfix expression
however there are 3rd party libs which do it for you

http://www.japisoft.com/formula/
0
 
johnmarcoAuthor Commented:
Please provide a code which will fit to my 1st code above. Merge/Combine them.
0
Question has a verified solution.

Are you are experiencing a similar issue? Get a personalized answer when you ask a related question.

Have a better answer? Share it in a comment.

All Courses

From novice to tech pro — start learning today.