investmenttable.java

这个是我老师给的关于Java核心技术2的第6章的源代码

/**
   @version 1.01 2004-08-22
   @author Cay Horstmann
*/

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

/**
   This program shows how to build a table from a table model.
*/
public class InvestmentTable
{  
   public static void main(String[] args)
   {  
      JFrame frame = new InvestmentTableFrame();
      frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
      frame.setVisible(true);
   }
}

/**
   This frame contains the investment table.
*/
class InvestmentTableFrame extends JFrame
{  
   public InvestmentTableFrame()
   {  
      setTitle("InvestmentTable");
      setSize(DEFAULT_WIDTH, DEFAULT_HEIGHT);

      TableModel model = new InvestmentTableModel(30, 5, 10);
      JTable table = new JTable(model);
      add(new JScrollPane(table));
   }

   private static final int DEFAULT_WIDTH = 600;
   private static final int DEFAULT_HEIGHT = 300;
}

/** 
   This table model computes the cell entries each time they
   are requested. The table contents shows the growth of
   an investment for a number of years under different interest
   rates.
*/
class InvestmentTableModel extends AbstractTableModel
{  
   /**
      Constructs an investment table model.
      @param y the number of years
      @param r1 the lowest interest rate to tabulate
      @param r2 the highest interest rate to tabulate
   */
   public InvestmentTableModel(int y, int r1, int r2)
   {  
      years = y;
      minRate = r1;
      maxRate = r2;
   }

   public int getRowCount() { return years; }

   public int getColumnCount() { return maxRate - minRate + 1; }

   public Object getValueAt(int r, int c)
   {  
      double rate = (c + minRate) / 100.0;
      int nperiods = r;
      double futureBalance = INITIAL_BALANCE * Math.pow(1 + rate, nperiods);
      return String.format("%.2f", futureBalance);
   }

   public String getColumnName(int c) { return (c + minRate) + "%"; }

   private int years;
   private int minRate;
   private int maxRate;

   private static double INITIAL_BALANCE = 100000.0;
}