复利计算结对再升级
1.这次主要把界面弄好看点，更加方便，不再杂乱无章。
2.每次输入完数据后，会清除上一次的记录，但会保存到 投资记录 ，可以点击查看。
搭档:马嘉诚
博客园地址:http://www.cnblogs.com/mafu0420
package ch; import java.awt.BorderLayout; import java.awt.Dimension; import java.awt.FlowLayout; import java.awt.Font; import java.awt.GridLayout; import java.awt.Toolkit; import java.awt.event.ActionEvent; import java.awt.event.ActionListener; import java.text.NumberFormat; import javax.swing.AbstractButton; import javax.swing.BorderFactory; import javax.swing.JButton; import javax.swing.JFrame; import javax.swing.JLabel; import javax.swing.JOptionPane; import javax.swing.JPanel; import javax.swing.JRadioButtonMenuItem; import javax.swing.JScrollPane; import javax.swing.JTextArea; import javax.swing.JTextField; public class fuli 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 JTextArea text; private JPanel leftpanel = new JPanel(); private AbstractButton leftpanelr= new JRadioButtonMenuItem("每年添加一定的本金"); public double[] a = new double[100]; public double[] b = new double[100]; int input = 0; public fuli() { creatComponents() ; layoutComponents(); registerHandlers(); setTitle("复利存款计算器"); 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("期望值 "); 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("计算"); c1.setFont(new Font("宋体",Font.BOLD,15)); c2=new JButton("清除"); c2.setFont(new Font("宋体",Font.BOLD,15)); c3=new JButton("投资记录"); c3.setFont(new Font("宋体",Font.BOLD,15)); text=new JTextArea(); } private void layoutComponents() { 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 panel6=new JPanel(); panel6.add(a4); panel6.add(b4); JPanel panel4=new JPanel(); panel4.add(c1); panel4.add(c2); panel4.add(c3); JPanel leftpanel=new JPanel(new GridLayout(5,2)); leftpanel.add(panel1); leftpanel.add(panel2); leftpanel.add(panel3); leftpanel.add(panel6); leftpanel.add(panel4); JScrollPane panel5=new JScrollPane(text); panel5.setPreferredSize(new Dimension(300,200)); add(leftpanel); add(panel5); } private void registerHandlers() { c1ActionEventHander hander1 = new c1ActionEventHander(); c1.addActionListener(hander1); c2ActionEventHander hander2 = new c2ActionEventHander(); c2.addActionListener(hander2); c3ActionEventHander hander4 = new c3ActionEventHander(); c3.addActionListener(hander4); } private class c1ActionEventHander implements ActionListener { public void actionPerformed(ActionEvent e) { double principal = 0; double amount = 0; double rate = 0; int n = 0; NumberFormat currencyformatter = NumberFormat.getCurrencyInstance(); // 字符串转化为数字 String output = "年" + "/" + "复利存款"; int year = 1; int result; if (b1.getText().equals("") && b2.getText() != null && b3.getText() != null && b4.getText() != null) { // 计算本金 try { rate = Double.parseDouble(b2.getText()); n = Integer.parseInt(b3.getText()); 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) + "\n"; text.setText(output); } catch (Exception e2) { // TODO: handle exception } } else if (b2.getText().equals("") && b1.getText() != null && b3.getText() != null && b4.getText() != null) // 求利率 { try { principal = Double.parseDouble(b1.getText()); // b1本金 n = Integer.parseInt(b3.getText()); // b3年份 amount = Double.parseDouble(b4.getText()); // b4期望值 } catch (Exception e2) { // TODO: handle exception } rate = java.lang.StrictMath.pow(amount / principal, 1.0 / n) - 1; output = "利率" + rate + "\n"; text.setText(output); } else if (b3.getText().equals("") && b1.getText() != null && b2.getText() != null && b4.getText() != null) // 求年份 { try { principal = Double.parseDouble(b1.getText()); // b1本金 amount = Double.parseDouble(b4.getText()); // b4期望值 rate = Double.parseDouble(b2.getText()); } catch (Exception e2) { // TODO: handle exception } double year2 = Math.log(amount / principal) / Math.log(1 + rate); output = "至少年数" + year2 + "\n"; text.setText(output); } else if (b4.getText().equals("") && b1.getText() != null && b3.getText() != null && b2.getText() != null) // 求期望值 { try { rate = Double.parseDouble(b2.getText()); n = Integer.parseInt(b3.getText()); principal = Double.parseDouble(b1.getText()); // b1本金 } catch (Exception e2) { // TODO: handle exception } double tempprincipal = principal; result = JOptionPane.showConfirmDialog(null, "是否每年进行投资？"); if (result == JOptionPane.YES_OPTION) { amount=CalculateA(year,n,principal,rate,tempprincipal); System.out.println("CalculateA(year,n,principal,rate,tempprincipal)"+year+n+principal+rate+tempprincipal); output += String.valueOf(year) + "\t\t\t" + currencyformatter.format(amount) + "\n"; } else { while (year <= n) { amount = principal * Math.pow(1 + rate, year); output += String.valueOf(year) + "\t\t\t" + currencyformatter.format(amount) + "\n"; year = year + 1; } } text.setText(output); int Isinfo = JOptionPane.showConfirmDialog(null, "是否投资？"); if (Isinfo == JOptionPane.YES_OPTION) { a[input] = principal; b[input] = amount; input += 1; } } else if (b1.getText() != null && b4.getText() != null && b3.getText() != null && b2.getText() != null) { JOptionPane.showMessageDialog(null, "请删除一个数据"); } else { JOptionPane.showMessageDialog(null, "请增加数据"); } } public double CalculateA(int years2,int n2,double principal2,double rate2,double tempprincipal2){ double amount2 = 0; while (years2 <= n2) { amount2 = principal2 * Math.pow(1 + rate2, years2) + tempprincipal2; years2 = years2 + 1; } return amount2; } } public double CalculateA1(int years2,int n2,double principal2,double rate2,double tempprincipal2){ double amount2 = 0; while (years2 <= n2) { amount2 = principal2 * Math.pow(1 + rate2, years2) + tempprincipal2; years2 = years2 + 1; } return amount2; } private double CalculateA(int year, int n, double principal, double rate, double tempprincipal) { // TODO 自动生成的方法存根 return 0; } private class c2ActionEventHander implements ActionListener { public void actionPerformed(ActionEvent e) { b1.setText(""); b2.setText(""); b3.setText(""); text.setText(""); } } public static void main(String[] args) { fuli frame=new fuli(); frame.setVisible(true); int Windowswidth = 500; int Windowsheight = 400; int width = Toolkit.getDefaultToolkit().getScreenSize().width; int height = Toolkit.getDefaultToolkit().getScreenSize().height; frame.setResizable(false); frame.setLocation((width - Windowswidth) / 2, (height - Windowsheight) / 2); // 窗口居中 } private class c3ActionEventHander implements ActionListener { public void actionPerformed(ActionEvent e) { String output = "交易记录：存入的本金/获得的收益"; int i = 0; while (a[i] != 0) { output = output + "\t\t" + a[i] + "/" + b[i] + "\n"; i += 1; } text.setText(output); } } }
