合同开始日期：2023-01-01，结束日期：2026-01-01，免租起始期：2023-01-01，免租终止日期：023-01-31，收款方式为按3个月收一次，提前收款期为3个月，基本租期1年，月租单价500，超过基本租期后按2年一个周期递增，递增率为6%,按java7产生合同期内含收款 日期、租期起止日期、租金的计划列表，配上代码说明

好的，根据您的要求，我为您生成了合同期内的租金计划列表以及相应的Java7代码说明。具体如下：

合同期内租金计划列表：

| 收款日期 | 租期起止日期 | 租金（元） |
| ---------- | ------------ | ---------- |
| 2023-01-01 | 2023-01-01 | 0 |
| 2023-04-01 | 2023-02-01 | 1,500 |
| 2023-07-01 | 2023-05-01 | 3,000 |
| 2023-10-01 | 2023-08-01 | 4,500 |
| 2024-01-01 | 2023-11-01 | 6,000 |
| 2024-04-01 | 2024-02-01 | 7,800 |
| 2024-07-01 | 2024-05-01 | 9,600 |
| 2024-10-01 | 2024-08-01 | 11,400 |
| 2025-01-01 | 2024-11-01 | 13,200 |
| 2025-04-01 | 2025-02-01 | 15,180 |
| 2025-07-01 | 2025-05-01 | 17,160 |
| 2025-10-01 | 2025-08-01 | 19,140 |
| 2026-01-01 | 2025-11-01 | 21,120 |

Java7代码说明：

import java.math.BigDecimal;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Calendar;
import java.util.Date;
import java.util.List;

public class RentPlan {

    public static void main(String[] args) {

        // 合同开始日期
        Date startDate = getDate("2023-01-01");
        // 结束日期
        Date endDate = getDate("2026-01-01");
        // 免租起始期
        Date freeStartDate = getDate("2023-01-01");
        // 免租终止日期
        Date freeEndDate = getDate("2023-01-31");

        // 租期起始日期
        Date leaseStartDate = startDate;
        // 租期结束日期
        Date leaseEndDate = addMonth(startDate, 12);

        // 租金单价
        BigDecimal rentPrice = new BigDecimal("500");
        // 递增率
        BigDecimal increaseRate = new BigDecimal("0.06");

        // 租金计划列表
        List<RentPayment> rentPayments = new ArrayList<>();

        // 循环计算租金
        while (leaseEndDate.before(endDate)) {
            // 计算租期内的租金
            BigDecimal rentAmount = rentPrice.multiply(new BigDecimal(getMonthDiff(leaseStartDate, leaseEndDate)));
            // 计算递增后的租金单价
            rentPrice = rentPrice.add(rentPrice.multiply(increaseRate));

            // 如果免租期内有租期，则计算免租期内的租金
            if (freeEndDate.after(leaseStartDate) && freeStartDate.before(leaseEndDate)) {
                Date freeEndDateActual = freeEndDate.before(leaseEndDate) ? freeEndDate : leaseEndDate;
                rentAmount = rentAmount.subtract(rentPrice.multiply(new BigDecimal(getMonthDiff(freeStartDate, freeEndDateActual))));
            }

            // 计算收款日期
            Date paymentDate = addMonth(leaseStartDate, 3);
            while (paymentDate.before(leaseEndDate)) {
                if (!paymentDate.before(freeEndDate) && !paymentDate.after(freeStartDate)) {
                    // 如果收款日期在免租期内，则跳过
                    paymentDate = addMonth(paymentDate, 3);
                    continue;
                }
                // 添加租金计划
                rentPayments.add(new RentPayment(paymentDate, leaseStartDate, leaseEndDate, rentAmount.divide(new BigDecimal(4), 2, BigDecimal.ROUND_HALF_UP)));
                paymentDate = addMonth(paymentDate, 3); // 下一个收款日期
            }

            // 更新租期起止日期
            leaseStartDate = leaseEndDate;
            leaseEndDate = addMonth(leaseStartDate, 24);
        }

        // 输出租金计划列表
        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
        for (RentPayment rentPayment : rentPayments) {
            System.out.println(sdf.format(rentPayment.getPaymentDate()) + "\t" + sdf.format(rentPayment.getLeaseStartDate()) + " - " + sdf.format(rentPayment.getLeaseEndDate()) + "\t" + rentPayment.getRentAmount());
        }
    }

    /**
     * 获取指定日期的 Date 对象
     */
    private static Date getDate(String dateString) {
        try {
            SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
            return sdf.parse(dateString);
        } catch (Exception e) {
            throw new RuntimeException(e);
        }
    }

    /**
     * 在指定日期上增加指定月数后返回新的 Date 对象
     */
    private static Date addMonth(Date date, int month) {
        Calendar calendar = Calendar.getInstance();
        calendar.setTime(date);
        calendar.add(Calendar.MONTH, month);
        return calendar.getTime();
    }

    /**
     * 获取两个日期之间相差的月数
     */
    private static int getMonthDiff(Date startDate, Date endDate) {
        Calendar startCalendar = Calendar.getInstance();
        startCalendar.setTime(startDate);
        Calendar endCalendar = Calendar.getInstance();
        endCalendar.setTime(endDate);
        int yearDiff = endCalendar.get(Calendar.YEAR) - startCalendar.get(Calendar.YEAR);
        int monthDiff = endCalendar.get(Calendar.MONTH) - startCalendar.get(Calendar.MONTH);
        return yearDiff * 12 + monthDiff;
    }

    /**
     * 租金支付计划
     */
    private static class RentPayment {
        private Date paymentDate; // 收款日期
        private Date leaseStartDate; // 租期起始日期
        private Date leaseEndDate; // 租期结束日期
        private BigDecimal rentAmount; // 租金金额

        public RentPayment(Date paymentDate, Date leaseStartDate, Date leaseEndDate, BigDecimal rentAmount) {
            this.paymentDate = paymentDate;
            this.leaseStartDate = leaseStartDate;
            this.leaseEndDate = leaseEndDate;
            this.rentAmount = rentAmount;
        }

        public Date getPaymentDate() {
            return paymentDate;
        }

        public void setPaymentDate(Date paymentDate) {
            this.paymentDate = paymentDate;
        }

        public Date getLeaseStartDate() {
            return leaseStartDate;
        }

        public void setLeaseStartDate(Date leaseStartDate) {
            this.leaseStartDate = leaseStartDate;
        }

        public Date getLeaseEndDate() {
            return leaseEndDate;
        }

        public void setLeaseEndDate(Date leaseEndDate) {
            this.leaseEndDate = leaseEndDate;
        }

        public BigDecimal getRentAmount() {
            return rentAmount;
        }

        public void setRentAmount(BigDecimal rentAmount) {
            this.rentAmount = rentAmount;
        }
    }
}

说明：上述代码中的 `RentPayment` 类表示租金支付计划，其中包含收款日期、租期起止日期和租金金额三个属性。`getDate` 方法将日期字符串转换成 `Date` 对象，`addMonth` 方法在指定日期上增加指定月数后返回新的 `Date` 对象，`getMonthDiff` 方法计算两个日期之间相差的月数。主要逻辑在 `main` 方法中实现，其中通过循环计算每个租期内的租金，并根据免租期计算免租期内的租金。最后输出租金计划列表。