集存款(复利单利)贷款为一体的计算器(最新版)

事先说明：由于篇幅有限，只展示部分代码和运行结果。

这段小代码是属于Fuli类的，使用try catch包围及使用if语句防止非法输入

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) {

                try {
                    rate = Double.parseDouble(b2.getText());
                    if(rate<0){
                        JOptionPane.showMessageDialog(null, "利率输入有误，请重新输入数字");
                        rate=0;
                    }
                    n = Integer.parseInt(b3.getText());
                    if(n<0){
                        JOptionPane.showMessageDialog(null, "年份输入有误，请重新输入数字");
                        n=0;
                    }
                    amount = Double.parseDouble(b4.getText());
                    if(amount<0){
                        JOptionPane.showMessageDialog(null, "期待值输入有误，请重新输入数字");
                        amount=0;
                    }
                } catch (Exception e2) {
                    // TODO: handle exception
                    JOptionPane.showMessageDialog(null, "数据输入有误，请重新输入数字");

                }

                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 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
                    if(principal<0){
                        JOptionPane.showMessageDialog(null, "本金输入有误，请重新输入数字");
                        principal=0;
                    }
                    n = Integer.parseInt(b3.getText()); // b3年份
                    if(n<0){
                        JOptionPane.showMessageDialog(null, "年份输入有误，请重新输入数字");
                        n=0;
                    }
                    amount = Double.parseDouble(b4.getText()); // b4期望值
                    if(amount<0){
                        JOptionPane.showMessageDialog(null, "期待值输入有误，请重新输入数字");
                        amount=0;
                    }
                } catch (Exception e2) {
                    // TODO: handle exception
                    JOptionPane.showMessageDialog(null, "数据输入有误，请重新输入数字");
                }

                rate = java.lang.StrictMath.pow(amount / principal, 1.0 / n) - 1;
                output = "利率" + rate + "
";
                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
                    if(principal<0){
                        JOptionPane.showMessageDialog(null, "本金输入有误，请重新输入数字");
                        principal=0;
                    }
                    amount = Double.parseDouble(b4.getText()); // b4期望值
                    if(amount<0){
                        JOptionPane.showMessageDialog(null, "期待值输入有误，请重新输入数字");
                        amount=0;
                    }
                    rate = Double.parseDouble(b2.getText());
                    if(rate<0){
                        JOptionPane.showMessageDialog(null, "利率输入有误，请重新输入数字");
                        rate=0;
                    }
                } catch (Exception e2) {
                    // TODO: handle exception
                    JOptionPane.showMessageDialog(null, "数据输入有误，请重新输入数字");
                }

        
                double year2=Math.log(amount/principal)/Math.log(1+rate);
                output = "至少年数" + year2 + "
";
                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());
                    if(rate<0){
                        JOptionPane.showMessageDialog(null, "利率输入有误，请重新输入数字");
                        rate=0;
                    }
                    n = Integer.parseInt(b3.getText());
                    if(n<0){
                        JOptionPane.showMessageDialog(null, "年份输入有误，请重新输入数字");
                        n=0;
                    }
                    principal = Double.parseDouble(b1.getText()); // b1本金
                    if(principal<0){
                        JOptionPane.showMessageDialog(null, "本金输入有误，请重新输入数字");
                        rate=0;
                    }
                } catch (Exception e2) {
                    // TODO: handle exception
                    JOptionPane.showMessageDialog(null, "数据输入有误，请重新输入数字");
                }

                double tempprincipal = principal;
                result = JOptionPane.showConfirmDialog(null, "是否每年添加本金");
                if (result == JOptionPane.YES_OPTION) {
                    while (year <= n) {
                        amount = principal * Math.pow(1 + rate, year)
                                + tempprincipal;
                        output += String.valueOf(year) + "			"
                                + currencyformatter.format(amount) + "
";
                        year = year + 1;
                    }
                } else {
                    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 (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");
            }

        }
    }

这段代码是登录界面代码

	private class MyItemListener implements ActionListener//处理事件
		{
			 public void actionPerformed(ActionEvent e){  
			Object bj = e.getSource(); // 获得事件源
			if (bj == deposit) { // 若是鼠标点击开始游戏按钮，则调用Mainclass()函数进入游戏

				new Fuli();
			} else if (bj == exit) // 若是点击结束按钮，则退出登录界面
				System.exit(0);
			else if(bj==credit){
				new Credit();
			}
		}

	}

　　

这部分是计算分期还贷款的代码

private class C1ActionEventHander implements ActionListener {
		public void actionPerformed(ActionEvent e) {
			String output = null;
			double principle=0;
			double rate=0;
			double time=0;
			double money=0;
			try {
				principle=Double.parseDouble(b1.getText());
				if(principle<0){
					JOptionPane.showMessageDialog(null, "输入的贷款金额有误，请重新输入");
					principle=0;
				}
				rate=Double.parseDouble(b2.getText());
				if(rate<0){
					JOptionPane.showMessageDialog(null, "输入的贷款利率有误，请重新输入");
					rate=0;
				}
				time=Double.parseDouble(b3.getText());
				if(time<0){
					JOptionPane.showMessageDialog(null, "输入的还款期限有误，请重新输入");
					time=0;
				}
			} catch (Exception e2) {
				// TODO: handle exception
				JOptionPane.showMessageDialog(null, "数据输入有误，请重新输入");
			}
			
		
			CalculjbButton();
			money=principle*rate*time+principle;
			double money2=money;
			double data=12/jbButton*time;
			money=money/data;
			output="本息:"+money2+"     每"+jbButton+"个月需要付"+money+"元";
			d1.setText(output);
		}
	}

　　

这个是登录界面：

这个是存款界面

这个是贷款主界面：

这两张是非法性输入处理：

这个是贷款运行演示：

总结：软件工程决定了软件的质量，一开始一旦设计不合理，后面需要花很长时间进行维护。比起实现功能，逻辑设计更加难

如需要源代码请联系QQ694335719或者微信lin694335719，也可上github下载浏览，仅做交流学习用途

github地址：https://github.com/hellolaona/text

如果可以，我希望能开发投资功能，提供最佳投资方案