复利及单利计算

1.客户说：帮我开发一个复利计算软件。

客户提出：

2.如果按照单利计算，本息又是多少呢？

3.假如30年之后要筹措到300万元的养老金，平均的年回报率是3%，那么，现在必须投入的本金是多少？

4.利率这么低，复利计算收益都这么厉害了，如果拿100万元去买年报酬率10%的股票，若一切顺利，过多长时间，100万元就变成200万元呢？ 

5.如果我希望在十年内将100万元变成200万元，应该找到报酬率在多少的投资工具来帮助我达成目标？如果想在5年后本金翻倍，报酬率就应至少为多少才行呢？

6.如果每年都将积蓄的3万元进行投资，每年都能获得3%的回报，然后将这些本利之和连同年金再投入新一轮的投资，那么，30年后资产总值将变为多少？如果换成每月定投3000呢？

import java.awt.Color;
import java.awt.Container;
import java.awt.Dimension;
import java.awt.FlowLayout;
import java.awt.Font;
import java.awt.Graphics;
import java.awt.GridLayout;
import java.awt.Image;
import java.awt.Toolkit;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.text.NumberFormat;

import javax.swing.ImageIcon;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTextArea;
import javax.swing.JTextField;
import javax.swing.border.LineBorder;

public class test  extends JFrame
{
    private JLabel a1;
    private JLabel a2;
    private JLabel a3;
    private JLabel a4;
    private JTextField b1;
    private JTextField b2;
    private JTextField b3;
    private JTextField b4;
    private JButton c1;
    private JButton c2;
    private JButton c3;
    private JButton c4;
    private JTextArea text;
    public test()
    {
        creatComponents()    ;
        layoutComponents();
        registerHandlers();
        setTitle("存款应用程序");
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        pack();
    }
    private void  creatComponents()    
    {
        a1=new JLabel("本  金 ");
        a1.setFont(new Font("宋体",Font.BOLD,18));
        a2=new JLabel("年利率 ");
        a2.setFont(new Font("宋体",Font.BOLD,18));
        a3=new JLabel("年 数 ");
        a3.setFont(new Font("宋体",Font.BOLD,18));
        a4=new JLabel("本息 ");
        a4.setFont(new Font("宋体",Font.BOLD,18));
        
        
        
        b1=new JTextField(10);
        b2=new JTextField(10);
        b3=new JTextField(10);
        b4=new JTextField(10);
        c1=new JButton("复利");
        c1.setFont(new Font("宋体",Font.BOLD,15));
        c3=new JButton("单利");
        c3.setFont(new Font("宋体",Font.BOLD,15));
        c4=new JButton("定投");
        c4.setFont(new Font("宋体",Font.BOLD,15));
        c2=new JButton("清除");
        c2.setFont(new Font("宋体",Font.BOLD,15));
        text=new JTextArea();
    }
    private void layoutComponents()
    {
        //Container c=this.getContentPane();    
        setLayout(new FlowLayout());
        JPanel panel1=new JPanel();
        panel1.add(a1);
        panel1.add(b1);
        JPanel panel2=new JPanel();
        panel2.add(a2);
        panel2.add(b2);
        JPanel panel3=new JPanel();
        panel3.add(a3);
        panel3.add(b3);
        JPanel panel4=new JPanel();
        panel3.add(a4);
        panel3.add(b4);
        JPanel panel5=new JPanel();
        panel4.add(c1);
        panel4.add(c3);
        panel4.add(c4);
        panel4.add(c2);
        JPanel  leftpanel=new JPanel(new GridLayout(6,2));
        leftpanel.add(panel1);
        leftpanel.add(panel2);
        leftpanel.add(panel3);
        leftpanel.add(panel4);
        leftpanel.add(panel5);
        JScrollPane panel6=new JScrollPane(text);
        panel6.setPreferredSize(new Dimension(250,100));
        add(leftpanel);
        add(panel6);
    }
    private  void registerHandlers()
    {
         c1ActionEventHander hander1=new  c1ActionEventHander();
         c1.addActionListener(hander1);
         c2ActionEventHander hander2=new  c2ActionEventHander();
         c2.addActionListener(hander2);
    c3ActionEventHander hander3=new  c3ActionEventHander();
        c3.addActionListener(hander3);
        c4ActionEventHander hander4=new  c4ActionEventHander();
        c4.addActionListener(hander4);
     
    }
    private class c1ActionEventHander implements ActionListener
    {
        public void actionPerformed(ActionEvent e)
        {
            double principal;
            double amount;
            double rate;
            int n;
            NumberFormat currencyformatter=NumberFormat.getCurrencyInstance();
            String output="年"+"/t"+"复利存款"+"/n";
             int year =1;
           //  principal=Double.parseDouble(b1.getText());
             rate=Double.parseDouble(b2.getText()); 
             n=Integer.parseInt(b3.getText());
             if(b1.getText().equals(""))
             {
                 if (b4.getText().equals(""))
                 {
                     JOptionPane.showMessageDialog(null, "请输入本金或者本息");
                
                 }
                 else{
                amount = Double.parseDouble(b4.getText());
                principal=0;
                while (year <= n) {
                    principal=amount/(Math.pow(1 + rate, year));
                    year = year + 1;
                }
                
                output="本金"+currencyformatter.format(principal) + "
";
                text.setText(output);
            }
        }
        else {
            principal = Double.parseDouble(b1.getText()); // 字符串转化为数字
            
            if (b4.getText().equals("")) {
                while (year <= n) {
                    amount = principal * Math.pow(1 + rate, year);
                    output += String.valueOf(year) + "	"+ currencyformatter.format(amount) + "
";
                    year = year + 1;
                }

                text.setText(output);
                }
            else if (b3.getText().equals("")) {
                amount = Double.parseDouble(b4.getText());
                while (year <= n) {
                    rate=Math.pow(amount/principal,1/year)-1;
                    year = year + 1;
                }
                
                output="本金"+currencyformatter.format(principal) + "
";
                text.setText(output);
            }
            else{
                JOptionPane.showMessageDialog(null, "本金和本息输入一个即可");
            }
        }
}
}
    private class  c2ActionEventHander implements ActionListener
    {
        public void actionPerformed(ActionEvent e)
        {
            b1.setText("");
            b2.setText("");
            b3.setText("");
            text.setText("");
        }
    }
    private class c3ActionEventHander implements ActionListener {
        public void actionPerformed(ActionEvent e) {
            double principal;
            double amount;
            double rate;
            int n;
            NumberFormat currencyformatter = NumberFormat.getCurrencyInstance();
            String output = "年" + "/" + "单利存款";
            int year = 1;
            
            rate = Double.parseDouble(b2.getText());
            n = Integer.parseInt(b3.getText());
            if(b1.getText().equals(""))
            {
                if (b4.getText().equals(""))
                {
                    JOptionPane.showMessageDialog(null, "请输入本金或者本息");
                    
                }
                else{
                    amount = Double.parseDouble(b4.getText());
                    principal=0;
                    while (year <= n) {
                        principal = amount / (1 + rate* year);
                        year = year + 1;
                    }
                    
                    output="本金"+currencyformatter.format(principal) + "
";
                    text.setText(output);
                }
            }
            else {
                principal = Double.parseDouble(b1.getText()); // 字符串转化为数字
                
                if (b4.getText().equals("")) {
                    while (year <= n) {
                        amount = principal * (1 + rate* year);
                        output += String.valueOf(year) + "	"
                                + currencyformatter.format(amount) + "
";
                        year = year + 1;
                    }
    
                    text.setText(output);
                    }
            else if (b3.getText().equals("")) {
                amount = Double.parseDouble(b4.getText());
                while (year <= n) {
                    rate=amount/principal/year-1;
                    year = year + 1;
                }
                
                output="本金"+currencyformatter.format(principal) + "
";
                text.setText(output);
            }
                else{
                    JOptionPane.showMessageDialog(null, "本金和本息输入一个即可");
                }
            }
            
        }
    }
    private class c4ActionEventHander implements ActionListener
    {
    public void actionPerformed(ActionEvent e)
    {
        double principal;//本金
        double amount;//本息
        double rate;//利率
        int n;//年数
        NumberFormat currencyformatter=NumberFormat.getCurrencyInstance();
        String output="年"+"/t"+"存款"+"/n";
         int year =1;
         amount=Double.parseDouble(b4.getText());
         rate=Double.parseDouble(b2.getText()); 
         n=Integer.parseInt(b3.getText());
         principal=amount/Math.pow(1+rate,year);
        output=String.valueOf(year)+"	"+currencyformatter.format(principal)+"
";
         text.setText(output);
        
    }
    }
    public static void main(String[] args)
    {
         test frame=new test();
        frame.setVisible(true);
        frame.setSize(600,450); 
      frame.setResizable(false);
    }
}

 

所用语言及工具：java,eclipse

回顾：

前两次的代码都是简单的，通过同学的演示，我尝试写出一个窗口，以便管理以及修改代码，但是仍然有些不足，这是我在前两次的基础上进行修改，同时对于不懂得也借助了网络查询。

工作量：大概6小时（借助网络资源，而且程序还没完善）还需要改进

自我评价：

自己的编程能力还是很差，不能学会学以致用