[Bug] WriteCellData 方法如果传入 java.sql.Date 会报错

[kt286]

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Fesod version

1.3.0

JDK version

17

Operating system

No response

Steps To Reproduce

Mybatis 3.5.17 之后的版本，date类型的数据返回的是 java.sql.Date 而不是 java.util.Date，此时在 WriteCellData 方法中调用 dateValue.toInstant() 会报错

    /**
     * Constructor for creating a WriteCellData object with a Date value.
     *
     * @param dateValue The Date value to be written to the cell.
     * @throws IllegalArgumentException If the date value is null.
     */
    public WriteCellData(Date dateValue) {
        super();
        if (dateValue == null) {
            throw new IllegalArgumentException("DateValue can not be null");
        }
        setType(CellDataTypeEnum.DATE);
        this.dateValue = LocalDateTime.ofInstant(dateValue.toInstant(), ZoneId.systemDefault());
    }

参考链接
mybatis/mybatis-3@28af7e9#diff-3100284b93f6e47f7e09229bac897dc14edbb2e162002f24e804113f49d8b6a6R44-R52

Current Behavior

throw new java.lang.UnsupportedOperationException();

Expected Behavior

正常

Anything else?

No response

Are you willing to submit a PR?

• I'm willing to submit a PR!

[bengbengbalabalabeng]

Could you please provide a minimal reproducible demo.

By default, MyBatis maps Java Bean date fields to java.util.Date, which is handled by the built‑in DateTypeHandler.
Could you confirm whether your entity explicitly declares the field as java.sql.Date?

(I think this does not seem to be a bug in Fesod itself, but rather related to how MyBatis handles date types.)

[ongdisheng]

Hi @kt286, I agree with @bengbengbalabalabeng where this seems related to how MyBatis handles date types. On top of that, I noticed this issue has been fixed in MyBatis. See this commit: mybatis/mybatis-3@3ca9771
It should be available in MyBatis 3.5.19. Could you try upgrading to see if that resolves the issue?

[kt286]

Thanks, after upgrading to Mybatis 3.5.19 it indeed works normally, but I think some additional handling might be necessary. Although this time it was Mybatis's issue, after all, java.sql.Date inherits from java.util.Date. In other scenarios, it's still possible to directly pass a java.util.Date object.

The minimal reproducible demo is as follows:

package org.example;

import cn.idev.excel.FastExcel;
import lombok.Data;

import java.util.ArrayList;
import java.util.List;


//TIP To <b>Run</b> code, press <shortcut actionId="Run"/> or
// click the <icon src="AllIcons.Actions.Execute"/> icon in the gutter.
public class Main {
    public static void main(String[] args) {
        List<Test> list = new ArrayList<>();

        Test test1 = new Test();
        test1.setNumber(1);
        test1.setDate(java.sql.Date.valueOf("2025-10-12"));

        list.add(test1);

        FastExcel.write("C:\\Workspace\\text.xlsx").sheet().doWrite(list);
    }

    @Data
    public static class Test {
        private int number;
        private java.util.Date date;
    }
}

[ongdisheng]

Hi @kt286, Thank you for providing the reproducible demo! I've investigated the problem and created a potential fix that handles both java.util.Date and java.sql.Date:

public WriteCellData(Date dateValue) {
    super();
    if (dateValue == null) {
        throw new IllegalArgumentException("DateValue can not be null");
    }
    setType(CellDataTypeEnum.DATE);
    // Use getTime() which works for both java.util.Date and java.sql.Date
    this.dateValue = LocalDateTime.ofInstant(
        Instant.ofEpochMilli(dateValue.getTime()),
        ZoneId.systemDefault()
    );
}

This approach works for both types since getTime() is available on both classes. However, I think this might need feedback from the project maintainers to see if this is the right approach.

[delei]

Thank you all for your feedback.

IMO, I believe both types of Date are commonly used, and it would be beneficial if we could support both simultaneously. Please feel free to submit a pull request at any time.