[Bug] Custom converters registered via registerConverter() are never used during write — silently falls back to the built-in converter, or throws "Converter not found" if none exists

[roysti10]

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Fesod version

2.0.2-incubating

JDK version

11

Operating system

Windows 11

Steps To Reproduce

public class AlwaysZeroIntegerConverter implements Converter<Integer> {
    public Class<?> supportJavaTypeKey() { return Integer.class; }
    public CellDataTypeEnum supportExcelTypeKey() { return CellDataTypeEnum.NUMBER; }

    public Integer convertToJavaData(...) { return 0; }   // deliberately wrong, so it's unmistakable
    public WriteCellData<?> convertToExcelData(WriteConverterContext<Integer> ctx) {
        return new WriteCellData<>(new BigDecimal(999));   // deliberately wrong, so it's unmistakable
    }
}

public class IntRow {
    @ExcelProperty("n")
    private Integer n;   // will be set to 42
}

// ...
IntRow row = new IntRow();
row.setN(42);

FesodSheet.write(file, IntRow.class)
    .registerConverter(new AlwaysZeroIntegerConverter())
    .sheet()
    .doWrite(List.of(row));

Current Behavior

It writes 42 into the xlsx file, instead of 999

Expected Behavior

it should write 999 into the xlsx file

Anything else?

RCA: Built in write converters are keyed by Java Type but these custom converters are keyed by both java type and excel cell type. At the write time only converts keyed by java type are searched causing the write path to completely ignore the custom converters

Fix would be to key it by java type only in the AbstractWriteHolder

Happy to share a PR for this!

Are you willing to submit a PR?

• I'm willing to submit a PR!