我编写的计算按揭记录明细类

柔光的暖阳◎ 2022-04-16 01:11 54阅读 0赞

计算按揭明细记录的类：

import java.io.FileInputStream;

import java.io.FileNotFoundException;
    import java.io.IOException;
    import java.io.InputStream;
    import java.math.RoundingMode;
    import java.text.DecimalFormat;
    import java.text.ParseException;
    import java.text.SimpleDateFormat;
    import java.util.*;
    
    /**
     * @author Alfoo Liu <dmcpxy@Gmail.com>
     * @since 2011-11-01 09:58
     */
    public class MortgageCalculator {
        final static String default_config_file_name = "MortgageCalculator.properties";
        SimpleDateFormat format = new SimpleDateFormat("yyyyMMdd");
        DecimalFormat df = new DecimalFormat("0.00");
        DecimalFormat dfl = new DecimalFormat("0.0000");
        private Properties configuration = new Properties();
    
        public MortgageCalculator(String configFilePath) {
            df.setRoundingMode(RoundingMode.UP);
            dfl.setRoundingMode(RoundingMode.UP);
    
            loadProperties(configFilePath);
        }
    
        public void loadProperties(String filePath) {
            try {
                FileInputStream fileInputStream = new FileInputStream(filePath);
                configuration.load(fileInputStream);
            } catch (FileNotFoundException fnfe) {
                InputStream resourceAsStream = getClass().getResourceAsStream(default_config_file_name);
                try {
                    configuration.load(resourceAsStream);
                } catch (IOException e) {
                    System.err.println("failed read config file: " + default_config_file_name + " from classpath "
                            + this.getClass().getPackage().getName());
                }
            } catch (IOException ioe) {
                System.err.println("failed read config file: " + filePath);
            }
        }
    
        public Properties getConfiguration() {
            return configuration;
        }
    
        public void printMortgageDetailInfo(List<MortgageBean> payList) {
            for (MortgageBean bean : payList) {
                System.out.println(bean.toString());
            }
        }
    
        /**
         * calculte method: (total - benjin_money * cur_month) * rate_month + benjin_money;
         * @return List pay list;
         */
        public List<MortgageBean> calculate() {
            List<MortgageBean> payList = new ArrayList<MortgageBean>();
            int period = getPeriod(), restPeriod;
            double totalPrincipal = getTotalPrincipal();
            String currentDateStr = getFirstPayDate();
            double restPrincipal = totalPrincipal, interest, principal, rate, monthRate;
    
            rate = getFirstPayRate();
    
            Date currentDate;
    
            MortgageBean mortgageBean;
            for (int i = 1; i <= period; i++) {
                monthRate = toDouble( dfl.format( rate / 12 ) );
    
                restPeriod = period - i + 1;
                principal = toDouble( df.format( (restPrincipal / restPeriod) ) );
                String tiqianhuankuanDate = getConfiguration().getProperty("tiqianhuankuanDate");
                if (null != tiqianhuankuanDate && tiqianhuankuanDate.equals(currentDateStr)) {
                    principal += toDouble( getConfiguration().getProperty("tiqianhuankuanMoney", "0") );
                }
                interest = toDouble( df.format( (restPrincipal - principal) * monthRate ) );
    
                restPrincipal = toDouble(df.format(restPrincipal - principal));
    
    
                currentDate = getDate(currentDateStr);
    
                mortgageBean = new MortgageBean(currentDate, i, rate, toDouble( df.format(principal + interest) ),
                        principal, interest, restPrincipal);
                payList.add(mortgageBean);
    
                currentDateStr = getNextPayDate(currentDate);
                rate = toDouble( dfl.format( getNextPayRate(currentDate, rate) ) );
            }
    
            return payList;
        }
    
        protected double toDouble(String dv) {
            return Double.parseDouble(dv);
        }
    
        private double getDiscount() {
            return Double.parseDouble(getConfiguration().getProperty("rateDiscount"));
        }
    
        private int getPeriod() {
            return Integer.parseInt( getConfiguration().getProperty("periods") );
        }
    
        private double getTotalPrincipal() {
            return Double.parseDouble(getConfiguration().getProperty("totalPrincipal"));
        }
    
        private String getFirstPayDate() {
            return configuration.getProperty("firstMortgageDate");
        }
    
        private Date getDate(String date) {
            try {
                return format.parse(date);
            } catch (ParseException e) {
                System.err.println("invalid date format: " + date);
                return null;
            }
        }
    
        private double getFirstPayRate() {
            String firstPayDate = "MortgageRate." + getFirstPayDate();
            String firstRateStr = configuration.getProperty(firstPayDate);
            double v = Double.parseDouble(firstRateStr)/100 * getDiscount();
            return toDouble( dfl.format(v) );
        }
    
        private String getNextPayDate(Date date) {
            GregorianCalendar gc = new GregorianCalendar(Locale.SIMPLIFIED_CHINESE);
            gc.setTime(date);
            gc.add(Calendar.MONTH, 1);
    
            Date nextMonth = gc.getTime();
            return format.format(nextMonth);
        }
    
        private double getNextPayRate(Date date, double lastPayRate) {
            String property = configuration.getProperty("MortgageRate." + getNextPayDate(date));
    
            if (null == property) {
                return lastPayRate;
            }
    
            double v = Double.parseDouble(property) * getDiscount() / 100;
            return toDouble( dfl.format(v) );
        }
    
    
        public static void main(String[] args) {
            MortgageCalculator calculator = new MortgageCalculator("");
            calculator.loadProperties("");
            List<MortgageBean> mortgageBeanList = calculator.calculate();
            calculator.printMortgageDetailInfo(mortgageBeanList);
        }
    }

按揭的Bean类：

import java.io.Serializable;
    import java.text.DecimalFormat;
    import java.text.SimpleDateFormat;
    import java.util.Date;
    
    /**
     * @author Alfoo Liu <dmcpxy@Gmail.com>
     * @since 2011-11-01 10:36
     */
    public class MortgageBean implements Serializable {
        DecimalFormat df = new DecimalFormat("0.00");
        DecimalFormat dfl = new DecimalFormat("0.00%");
        final static SimpleDateFormat format = new SimpleDateFormat("yyyy-MM-dd");
        final static String DELIMETER = "\t\t";
        private Date mortgageDate;
        private int mortgageNumber;
        private double rate;
        /*当前月份还的款总额*/
        private double currentMonthPay;
        /*当前月份还的本金*/
        private double currentMonthPrincipal;
        /*当前月还的利息*/
        private double currentMonthInterest;
        /*剩余本金*/
        private double restPrincipal;
    
        public MortgageBean(Date mortgageDate, int mortgageNumber, double rate, double currentMonthPay,
                            double currentMonthPrincipal, double currentMonthInterest, double restPrincipal) {
            this.mortgageDate = mortgageDate;
            this.mortgageNumber = mortgageNumber;
            this.rate = rate;
            this.currentMonthPay = currentMonthPay;
            this.currentMonthPrincipal = currentMonthPrincipal;
            this.currentMonthInterest = currentMonthInterest;
            this.restPrincipal = restPrincipal;
        }
    
        public Date getMortgageDate() {
            return mortgageDate;
        }
    
        public void setMortgageDate(Date mortgageDate) {
            this.mortgageDate = mortgageDate;
        }
    
        public int getMortgageNumber() {
            return mortgageNumber;
        }
    
        public void setMortgageNumber(int mortgageNumber) {
            this.mortgageNumber = mortgageNumber;
        }
    
        public double getRate() {
            return rate;
        }
    
        public void setRate(float rate) {
            this.rate = rate;
        }
    
        public double getCurrentMonthPay() {
            return currentMonthPay;
        }
    
        public void setCurrentMonthPay(float currentMonthPay) {
            this.currentMonthPay = currentMonthPay;
        }
    
        public double getCurrentMonthPrincipal() {
            return currentMonthPrincipal;
        }
    
        public void setCurrentMonthPrincipal(float currentMonthPrincipal) {
            this.currentMonthPrincipal = currentMonthPrincipal;
        }
    
        public double getCurrentMonthInterest() {
            return currentMonthInterest;
        }
    
        public void setCurrentMonthInterest(float currentMonthInterest) {
            this.currentMonthInterest = currentMonthInterest;
        }
    
        public double getRestPrincipal() {
            return restPrincipal;
        }
    
        public void setRestPrincipal(float restPrincipal) {
            this.restPrincipal = restPrincipal;
        }
    
        @Override public String toString() {
            StringBuilder sb = new StringBuilder();
    
            sb.append(format.format( getMortgageDate() ));
            sb.append(DELIMETER);
            sb.append( getMortgageNumber() );
            sb.append(DELIMETER);
    
            sb.append( dfl.format(getRate()) );
            sb.append(DELIMETER);
            sb.append( df.format(getCurrentMonthPay()) );
            sb.append(DELIMETER);
            sb.append( df.format(getCurrentMonthPrincipal()) );
            sb.append(DELIMETER);
            sb.append( df.format(getCurrentMonthInterest()) );
            sb.append(DELIMETER);
            sb.append( df.format(getRestPrincipal()) );
    
            return sb.toString();
        }
    }

配置文件，放在这个类相同的目录下：

#如果你家的还款日期是26号，则把日期的末两位全部改成26，日期格式为yyyyMMdd
    #format: yyyyMMdd
    firstMortgageDate=20100326
    #第一次还款的利率
    firstMortgageRate=5.94
    #利率折扣
    rateDiscount=0.7
    #Unit: Month
    periods=240
    #Unit: yuan
    totalPrincipal=300000
    #提前还款月份
    tiqianhuankuanDate=20111226
    #Unit: yuan
    tiqianhuankuanMoney=80000
    
    
    #各期还款利率
    MortgageRate.20100326=5.94
    MortgageRate.20101026=6.14
    MortgageRate.20101226=6.40
    MortgageRate.20110226=6.60
    MortgageRate.20110426=6.80
    MortgageRate.20110726=7.05