Need help||||||||||floating point error

Question

my code is this
import javax.swing.*;
import javax.swing.event.*;
import java.awt.*;
import java.awt.event.*;
import java.util.*;
import java.sql.*;
import java.math.*;
* This class implements the Portfolio tab appearing on the System Tabs.
* The purpose of this class is to implement a JTable that will list the details of all the companies
* listed under the selected portfolio, which the user will choose from the Choose Portfolio Tab.
public class PortfolioTable extends JPanel
     String t,totalPl,PPL;
     double CP=0;
     double total=0,overallPL=0;
     double totalperChange=0;
* The PortfolioTable Class Constructor. This Constructor creates a JTable, and populates the
* JTable with the details of the companies under the selected portfolio
public PortfolioTable()
          // Creating objects for the various panels present
          JPanel p1 = new JPanel();
          JPanel p2 = new JPanel();
          JPanel p3 = new JPanel();
          JPanel p4 = new JPanel();
          JPanel p5 = new JPanel();
          // A boolean type variable
          boolean flag = false;
          // Creating a label. This label is shown when no companies are present under any selected portfolio, or no portfolio is selected.
          JLabel label = new JLabel("THERE ARE NO COMPANIES WITHIN THE SELECTED PORTFOLIO. TO ADD A COMPANY PLEASE GOTO THE 'PORTFOLIO ACTIONS' MENU ITEM AND THEN ADD A COMPANY.");
          JLabel label1 = new JLabel("Overall Amount Invested ");
          JLabel label2 = new JLabel("Overall Profit/Loss ");
          JLabel label3 = new JLabel("Overall Percentage Change");
          JLabel label4 = new JLabel("Amount Invested");
          JLabel label5 = new JLabel(" Profit/Loss ");
          JLabel label6 = new JLabel(" Percentage Change");
          // The following string array holds the JTable Column headers.
          String[] columnNames = {"Company Name","Previous Close (p)","Open (p)","Bid (p)","Ask (p)","Change Value","No. of Shares","Total (Pd)","Current (Pd)","Commission","Profit/Loss (Pd)","% Change"};
          // Creating an object of the JTable
          JTable table;
          // The following variables are defined to communicate with the database.
          Connection     Conn;          // The Connection object variable
          Statement     Stmt;          // The Statement object variable.
          ResultSet     rs;               // The Resultset object variable.
          // Below I'm attempting to retrieve the JDBC-ODBC Class definition
          try
               Class.forName ("sun.jdbc.odbc.JdbcOdbcDriver");
          catch(ClassNotFoundException e)
               System.out.println("Unable to retrieve the JDBC-ODBC Bridge. Exiting.....");
               System.exit(1);
          int i = 0;
          try
               // Creating an database connection using the DSN - DataStorage
               Conn = DriverManager.getConnection("jdbc:odbc:DataStorage","","");
               Stmt = Conn.createStatement();
               String queryString = "select COMPANYNAME,PREVCLOSE,OPEN,BID,ASK,TODAYSCHANGE,NOOFSHARES,TOTPRICEPAID FROM CompanyDetails where UNIQUEID = " + Variables.getSelectedPortfolio ();
               // Executing the above SQL query. The values returned by the executeQuery statement is placed in the Resultset rs.
               rs = Stmt.executeQuery(queryString);
               // A counter variable. this counter is incremented for each record present in the table.
               // I'm following this procedure to show only the same number of JTable rows as the number of records.
               int count = 0;
               while (rs.next())
                    count ++;
               // Closing all Data Objects created above
               rs.close();
               Stmt.close();
               Conn.close();
               // Now since I know the number of records, I will initialize a String array only to the size as the number of rows present in the table.
               // As mentioned earlier the number of rows will be determined from the variable count, declared above.
               String rowData[][] = new String[count][12];
               // Instantiating the JTable object created above, with the declared Column headings and the row data.
               table = new JTable(rowData, columnNames);          
               // Creating an database connection using the DSN - DataStorage
               Conn = DriverManager.getConnection("jdbc:odbc:DataStorage","","");
               Stmt = Conn.createStatement();
               queryString = "select COMPANYNAME,PREVCLOSE,OPEN,BID,ASK,TODAYSCHANGE,NOOFSHARES,TOTPRICEPAID FROM CompanyDetails where UNIQUEID = " + Variables.getSelectedPortfolio ();
               // Executing the above SQL query. The values returned by the executeQuery statement is placed in the Resultset rs.
               rs = Stmt.executeQuery(queryString);
               int j = 0;
               // Getting the current Commision Rate. This value is retrieved from the database when the application is started and is stored in the
               // Application variable. The Variables class handles all by Application related work.
               String commissionVal = Variables.getCommisionValue ();
               // Retrieving all the records.
               while(rs.next())
                    flag = true;                                   // this variable is initialized to true to indicate that some records were found.
                    String companyName = rs.getString(1);     // the company value retrieved from the DB
                    String prevCloseStr = rs.getString(2);     // the Previous Close retrieved from the DB
                    String openPriceStr = rs.getString(3);     // the Open Price retrieved from the DB
                    String bidPriceStr = rs.getString(4);     // the Bid Price retrieved from the DB
                    String askPriceStr = rs.getString(5);     // the Ask Price retrieved from the DB
                    String todaysChg = rs.getString(6);     // the Today's Change retrieved from the DB
                    String noofShares = rs.getString(7);     // the No of Shares retrieved from the DB
                    String totPrice = rs.getString(8);     // the Total Price paid for the above shares retrieved from the DB
                    // Determining the Current Price, where it is calculated by = Current Price = Bid Price * No of Shares bought
                    double currPrice = Double.valueOf(bidPriceStr).doubleValue() * Double.valueOf (noofShares).doubleValue ();
                    // Since the Bid Price is in pence, therefore the Current Price will also be in cents. I now convert then into Pounds.
                    currPrice = currPrice/100;
                    // Determining the precision upto 2 decimal places.
                    currPrice = new java.math.BigDecimal(currPrice).setScale(2,java.math.BigDecimal.ROUND_HALF_EVEN).doubleValue ();
                    // Creating a string variable for the Current Price. This string will help me to place the value into the JTable
                    String currPriceStr = new String();
                    // calculating the profit loss. the Profit/Loss is calculated by the Current Price - Total Price. If negative then loss, if positive the profit.
                    double profitloss = currPrice - Double.valueOf(totPrice).doubleValue();
                    // Determining the precision upto 2 decimal places.
                    profitloss = new java.math.BigDecimal(profitloss).setScale(2,java.math.BigDecimal.ROUND_HALF_EVEN).doubleValue ();
                    // Creating a string variable for the Profit Loss. This string will help me to place the value into the JTable
                    String profitLossStr = new String();
                    // calculating the percentage change. The percentage Change is calculated by the profitloss/Total Price. the result value is divided by 100 to get in % profit or loss.
                    double perChange = (profitloss / Double.valueOf(totPrice).doubleValue()) * 100;
                    // Determining the precision upto 2 decimal places.
                    perChange = new java.math.BigDecimal(perChange).setScale(2,java.math.BigDecimal.ROUND_HALF_EVEN).doubleValue ();
                    // Creating a string variable for the Percentage Change. This string will help me to place the value into the JTable
                    String perChangeStr = new String();
                    // The following statements are populating the JTable columns with the appropriate values.
                    table.setValueAt(companyName,i,j);     // Company Name
                    j = j + 1;
                    table.setValueAt(prevCloseStr,i,j);     // Previous Close
                    j = j + 1;
                    table.setValueAt(openPriceStr,i,j);     // Open Price
                    j = j + 1;
                    table.setValueAt(bidPriceStr,i,j);     // Bid price
                    j = j + 1;
                    table.setValueAt(askPriceStr,i,j);     // Ask Price
                    j = j + 1;
                    table.setValueAt(todaysChg,i,j);     // Today's Change
                    j = j + 1;
                    table.setValueAt(noofShares,i,j);     // No of Shares
                    j = j + 1;
                    table.setValueAt(totPrice,i,j);          // Total Price Paid
                    j = j + 1;
                    table.setValueAt(currPriceStr.valueOf (currPrice),i,j);
                    j = j + 1;
                    table.setValueAt(commissionVal,i,j);     // Commission
                    j = j + 1;
                    table.setValueAt(profitLossStr.valueOf(profitloss),i,j);     // Profit/Loss
                    j = j + 1;     
                    table.setValueAt(perChangeStr.valueOf(perChange),i,j);          // Percentage Change
                    i = i + 1;
                    j = 0;
                    //currPrice = 0;
                    //profitloss = 0;
                    //perChange = 0;
               //JFrame frame=new ExitableJFrame();
//Container contentPane=frame.getContentPane();
                    total=total+Double.valueOf(totPrice).doubleValue();
                    currPrice = Double.valueOf(bidPriceStr).doubleValue() * Double.valueOf (noofShares).doubleValue ();
                    CP=CP+currPrice;
                    CP=CP/100;
                    overallPL=CP-total;
                    totalperChange=overallPL/total;     
                    totalperChange = new java.math.BigDecimal(totalperChange).setScale(2,java.math.BigDecimal.ROUND_HALF_EVEN).doubleValue ();
t=Double.toString(total);
                    label4.setText(t);
                    totalPl=Double.toString(overallPL);
                    label5.setText(totalPl);
                    PPL=Double.toString(totalperChange);
                    label6.setText(PPL);
                    p1.add(table.getTableHeader(), BorderLayout.NORTH);
                    p2.add(table);
                    p2.setLayout(new GridLayout(10,0,5,5));
                    p4.add(label1,BorderLayout.NORTH);
                    p4.add(label2,BorderLayout.SOUTH);
                    p4.add(label3,BorderLayout.NORTH);
                    p5.add(label4,BorderLayout.SOUTH);
                    p5.add(label5,BorderLayout.NORTH);
                    p5.add(label6,BorderLayout.SOUTH);
          catch(SQLException e)
               System.out.println(e.getMessage ());
          // Here I'm placing the various panels and the JTable onto the Frame
Box horibox1 = Box.createHorizontalBox();
horibox1.add(p1);
Box horibox2 = Box.createHorizontalBox();
horibox2.add(p2);
Box horibox3 = Box.createHorizontalBox();
horibox3.add(p4);
Box horibox4 = Box.createHorizontalBox();
horibox4.add(p5);
          if (!flag)
               p3.add(label);
Box veribox = Box.createVerticalBox();
veribox.add(horibox1);
veribox.add(Box.createGlue());
veribox.add(horibox2);
veribox.add(horibox3);
//veribox.add(Box.createGlue());
veribox.add(horibox4);
          if (!flag)
               veribox.add(p3);
               veribox.add(Box.createGlue());               
          this.add(veribox);
//main method for testing purposes
public static void main(String[] args)
// Create a JFrame
JFrame frame = new JFrame("Portfolio Summary");
// Create a Portfolio Table
PortfolioTable portfolioTableObj = new PortfolioTable();
// Add the Portfolio Table to the JFrame
frame.getContentPane().add(portfolioTableObj, BorderLayout.WEST);
// Set Jframe size
frame.setSize(800, 400);
// Set JFrame to visible
frame.setVisible(true);
     // set the close operation so that the Application terminates when closed
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
but when i run i get messege by calling applcaton.java i get
C:\JavaProjectnew>java Application
Exception in thread "main" java.lang.NullPointerException
at java.lang.FloatingDecimal.readJavaFormatString(Unknown Source)
at java.lang.Double.valueOf(Unknown Source)
at TradingHistory.<init>(TradingHistory.java:156)
at SystemTabs.<init>(SystemTabs.java:18)
at Application.<init>(Application.java:31)
at Application.main(Application.java:87)

Answer 1

sorry for trouble
actaually db's first record has the null value.it is solved now.
sorry again
sheetal